[Emc-users] Capto

[Roland Jollivet]

Hi Andy

I don't know if you adopted Capto from scratch, or had some already, but as
a new tooling system did you consider the Kennametal KM system?

See on Ebay

;

Or
https://www.kennametal.com/us/en/products/metalworking-tools/tool-holders-and-adapters/km/km-systems.html

Regards
Roland

On Mon, 8 Jan 2024 at 02:35, andy pugh  wrote:

> On Mon, 8 Jan 2024 at 00:25, Chris Morley 
> wrote:
>
> > I too have catpo 3,4 and 5 tools. I look forward to reading/seeing your
> adventure in this.
> > I also agree it would surely show off some of linuxcncs advantages!
>
> I am becoming really keen on Capto. It's like the best of all worlds.
> And it's super-short too.
>
> I discovered this weekend that the equation in the standards doesn't
> give even spacing around the circle. It's epicycles in Xi, 2Xi and
> 4Xi, so that's no surprise.
>
> Today I have been tabulating lookup tables at evenly spaced centre
> angles (successive approximation in Xi to get a target theta) and I
> have a HAL component ready to run.
>
> --
> atp
> "A motorcycle is a bicycle with a pandemonium attachment and is
> designed for the especial use of mechanical geniuses, daredevils and
> lunatics."
> — George Fitch, Atlanta Constitution Newspaper, 1912
>
>
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[Emc-users] How to treat rusted linear rails?

[Roland Jollivet]

Personally, I would use an electrolytic process with carbon and a power
source. Any other method would only further damage the rails.
You're 'plating' onto the rails, so no metal is lost. The rust gets reduced
back to Fe and can be brushed off.

Roland



On Mon, 11 Mar 2024 at 09:47, Viesturs Lācis 
wrote:

> Hello!
>
> Last year there was a chance to acquire Biesse machine for a a really
> low price so I surprised myself with pretty large and heavy Christmas
> present. Just put it in the workshop (where heating is not yet
> present) and was waiting for a warmer weather to start retrofitting it
> with LinuxCNC.
>
> Since this machine has spent at least several years in a shed - roof
> above it but no other protection against outside temperatures, I did
> not worry about adding one more winter to it.
>
> I have 2 questions:
> 1) are there any recommendations for outside temperature when trying
> to connect it to power? I want to see the status messages on
> servodrives - hopefully they are good (I have done 4 similar retrofits
> so I feel familiar with those old drives).
>
> 2) my main problem is the rust on linear rails. what is recommended
> procedure to treat this?
> Here is a picture that show the extent of the issue:
> https://pasteboard.co/C1EAn0w5t8KT.jpg
> What I did is brushing it with a piece of steel wool moisted with oil.
> I am not sure that it is sufficient so I would appreciate any tips on
> how to treat them.
>
> Viesturs
>
>
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[Emc-users] Semi OT: Variable speed DC drive for Fanuc brushed DC spindle drive

[Roland Jollivet]

I think you'd be aiming for a SCR drive, bought or self-made. They're
simple and lower cost.

Roland


On Sat, 10 Feb 2024 at 00:07, Leonardo Marsaglia 
wrote:

> Hello guys, I hope you're doing well
>
> We just purchased a Mori Seiki SL3 lathe that's going to be
> retrofitted with LCNC because it has no control.
>
> The machine has a brushed DC spindle motor and from what they told me the
> DC drive was not working (I would like to check this but I couldn't find
> any info or manuals for this drive, the model number of the drive is
> A20B-0008-0372/02). I would like to keep this motor because I like the idea
> of having high torque at low speeds because I plan to use a milling and
> hobbing attachment with this lathe.
>
> I'm trying to find DC speed controllers of 15 kW or so, just to take a look
> at what it's available but it seems difficult to find something that big.
> Do you guys recommend any particular brand or source to find such a speed
> controller?
>
> Thanks as always.
>
> Leonardo
>
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[Emc-users] Capto

[Roland Jollivet]

And here is a Capto profile being ground;
https://www.youtube.com/watch?v=ALRAiiMxTnk

Roland



On Tue, 2 Jan 2024 at 18:02, gene heskett  wrote:

> On 1/2/24 08:17, Adam McLeod wrote:
> > Fortunately, Sandvik standardized the Capto shank via ISO 26623. It is
> > called a "Polygonal taper interface with flange contact surface".  If
> > you search "capto iso polygon shank" in duckduckgo search engine right
> > now, you may find that there is a "preview" of that standard in a pdf
> > that probably has the details you're looking for near the top of the
> > search results.
> >
> > On 2024-01-01 9:04 p.m., Sam Sokolik wrote:
> >> boy - there doesn't seem to be much info on that shape.. It does look
> >> like
> >> it could be machined/ground with spindle synced motion..
> >>
> In that event, stretch the definition of spindle to include drives
> similar to the A drive on the G0704, or the B drive on my 6040.
>
> Those are both 3 phase stepper/servo's of 3nm power, both driving an
> rvs30 series worm drive for a 5/1 reduction.  These worms do have a half
> degree of backlash that may not be wholly consistent, but I'm carving
> buttress threads with them in synchronized motions, works fine.  Top
> speeds of something in the 400 rpm range.  At a speed your Z drive can
> track is a Sunday drive for that combo.
>
> We have the trig functions, and a simple multiply based on the
> remainder(mod) could easily return a triangular shape if its a sine. I'm
> positive I could come up with something on the 6040 doable with its 24k
> rev spindle and a CBN wheel. Not fast mind you, but doable. CBN is
> gawdawful $$$ and fragile in shapes and sizes I've found but it will
> "get the job done".  It is much like diamond but cuts HSS w/o destroying
> both as there is no carbon in it. Leaves no wire edge to be easily
> broken off and dulled, HSS is finished like a shaving mirror. All it
> should take is somebody better at math than me.
>
> >
> >
> > ___
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>
> Cheers, Gene Heskett.
> --
> "There are four boxes to be used in defense of liberty:
>   soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author, 1940)
> If we desire respect for the law, we must first make the law respectable.
>   - Louis D. Brandeis
>
>
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[Emc-users] OT: interesting mechanics

[Roland Jollivet]

I don't know if there is a use for such a thing, but it is an odd
arrangement;

https://www.youtube.com/watch?v=9xmLpHZG5gI


Roland

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[Emc-users] OT Fanuc ot-c cpu power supply A16B-1212-0950

[Roland Jollivet]

If you can obtain/borrow any thermal imaging device, then run with the PSU
with covers off and check every 5min. You should identify a cap-thermal
problem.



On Sat, 2 Dec 2023 at 21:14, John Dammeyer  wrote:

> > From: Chris Albertson [mailto:albertson.ch...@gmail.com]
> >
> > If it is a simple linear power supply, yes they are very easy to debug
> and
> > repair,  LIkey it is the caps.
> >
> > But switching power supplies are much harder to debug, You can guess it
> > might be the same issue but these have dozens of parts that can fail..
> In any
> > case, the cost to repair is small.
> >
>
> I disagree.  Switching power supplies are way more likely to fail from
> high ESR.  That the system runs for a short while and then fails is again a
> symptom of a capacitor overheating due to high ESR.  Or the voltage is
> right on the edge and as the cap warms up the heat results in a change that
> results in the power supply moving out of spec.There may even be enough
> heat developed on the board that a solder joint becomes unreliable.
>
> In the past even PC motherboards have been repaired by a wholesale swap of
> the electrolytics.
>
> So what I would do is an initial survey of the electrolytic capacitors
> inside the power supply and order a set.  That way the machine can still
> run for an hour or so a day while you wait for parts from a reputable
> source.Then replace the capacitor when they arrive.  That won't prevent
> the power supply from working again and it may well fix the 1 to 2 hour
> failure period.  In either case $30 or so worth of caps is cheap.
> John
>
>
>
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[Emc-users] OT: novel 3+ n axes

[Roland Jollivet]

Interesting, and it looks rigid enough for real work..

https://www.youtube.com/watch?v=4r4_uo6ZrAE
https://www.youtube.com/watch?v=ztW4JIbLSMs

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[Emc-users] OT: thread cutting

[Roland Jollivet]

I thought this is an interesting way of doing a 'peck' in thread turning.
More relevant because it's a deep square thread.

https://www.youtube.com/shorts/jT_4KKKCTbY

Roland

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[Emc-users] new tool table in linuxcnc master

[Roland Jollivet]

Just wondering, why would there be limit of 50?
Why not just make it 255? (surely the software doesn't care?)




On Mon, 2 Oct 2023 at 08:47, andrew beck  wrote:

> hey guys
>
> i see there is a new tool table in linuxcnc now.  looks like it has great
> potential
>
> https://linuxcnc.org/docs/devel/html/tooldatabase/tooldatabase.html
>
> i have a big mazak fh680 horizontal cnc mill  22tons and 80 tools
>
> linuxcnc used to have a max of 50 tools in tool table.  with the new table
> can that be changed now?  and has anyone built anything with it ready to be
> used yet?  i am interested in having a play now
>
> I am starting to think about retrofitting my cnc mill now and
> obviously want to be able to use all 80 tools.  its all bt50 tooling and i
> have about 90 holders ready to go that came with the machine
>
> regards
>
> Andrew
>
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[Emc-users] [Emc-developers] Trajectory planner shortcomings

[Roland Jollivet]

https://www.youtube.com/watch?v=KHB5ecOgr2o

I think the machine runs off a Beaglebone board.

Roland


On Thu, 6 Jul 2023 at 18:48, Chris Albertson 
wrote:

>
>
> > On Jul 6, 2023, at 9:22 AM, Roland Jollivet 
> wrote:
> >
> > The small 4-axis CNC machine,'Pocket Nc' uses LinuxCNC as far as I can
> > tell, and it seems to run just fine. Or does it?
>
> Does this device move all four axes at the same time while cutting?  Or
> does it use the fourth axis only to reposition the work?
>
>

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[Emc-users] [Emc-developers] Trajectory planner shortcomings

[Roland Jollivet]

The small 4-axis CNC machine,'Pocket Nc' uses LinuxCNC as far as I can
tell, and it seems to run just fine. Or does it?

Roland



On Tue, 4 Jul 2023 at 20:16, andy pugh  wrote:

> On Tue, 4 Jul 2023 at 18:34, Marius  wrote:
>
> > The problem seems to be that our trajectory planner lack the ability to
> > look ahead for any rotary axis. This means that a coordinated move that
> > includes a rotary move will be dysfunctional at best.
>
> It's not as bad as that.
>
> There is a 9-axis blending planner in Tormach, but it's not trivial to
> merge it with Linuxcnc due to divergence in the codebase.
>
> If we could get hold of the patches that introduced it to Tormach then
> we could look at integrating it, but doing it just from comparing the
> code sounds hard.
>
> --
> atp
> "A motorcycle is a bicycle with a pandemonium attachment and is
> designed for the especial use of mechanical geniuses, daredevils and
> lunatics."
> — George Fitch, Atlanta Constitution Newspaper, 1912
>
>
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[Emc-users] Drilling holes in the back of a stepper motor

[Roland Jollivet]

You have such a large flat surface area there. Design an encoder mount
plate of similar size where the end result is also has a flat surface.

Rough and clean the back of the motor up, then use a decent polyurethane
adhesive to bond it on. During the setup you could use a jig to keep it
concentric with the shaft.
Design it in such a way that you can still replace the encoder if need be.

Roland




On Sun, 25 Jun 2023 at 05:31, John Dammeyer  wrote:

> I want to add an encoder onto the back of this stepper motor.  I can
> install
> either a US Digital or a CUI since both mounting flanges can extend out
> near
> the edges of the back mounting plate.
>
>
>
> Is there any reason I can't clamp the motor in a vice and pop in two holes
> and tap them with a bottom tap at the spacing of the mounting flange?
>
> John
>
>
>
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[Emc-users] Medium voltage BLDC motor

[Roland Jollivet]

Actually, many of the sewing machine motors are now BLDC, with a controller
containing one of those power bricks. Here's one of the motors


They could be used as a spindle, but often the casing is so customised that
the re-work wouldn't be worth the effort. Like this one

Re-working might be worth it if you buy it as used. Buying as new wouldn't
be worth it.

Roland


On Tue, 25 Apr 2023 at 19:37, Chris Albertson 
wrote:

> For my robotics application, I'm drivnjg 100+ W BLDC motors with a driver
> that is maybe one square inch.  All you need are 6 mosfets and a tiny
> microcontroller.  I have a larger one that handles 50 amp per phase and it
> is about 6 sq. in.   Look at the typical drone, there are four 100+ W BLDC
> motors and four drivers are 35 mm square and handle four motors.   Stuff
> designed for the machine tool wold assumes you have apple space and power.
> Stuff designed to fly is typically very light and small.
>
> In any case, what it seems like you need is maybe a sewing machine motor.
> They are NOT "BLDC", work on line voltage and the speed is controlled by
> something like a light dimmer.
>
> On Tue, Apr 25, 2023 at 8:07 AM gene heskett  wrote:
>
> > On 4/25/23 09:27, Thaddeus Waldner wrote:
> > > What I mean is that specific driver would not fit into my space. I am
> > currently using a custom 24v BLDC driver that I built. But the only
> option
> > for power supply at this point is a wall wart that is about twice the
> size
> > of your typical laptop charger, which I’d like to eliminate.
> > >
> >
> > I'm with Todd, confused.
> > The psu for such a motor all by itself would be smaller than the psu for
> > the typical 3d printer, but  that is still going to be bigger than the
> > driver, which for one of the motors I'm thinking of needs a length of
> > 118mm, a depth from mount face to terminals of 86mm, and thickness of
> > 34mm, part of which is heat sink it does not need unless working really
> > hard.
> >
> > These new drivers can function with up to 90 volts, delivering 5 to 6
> > amps into the motor, dependent on the detected error. Motor current is
> > not fixed, but varies with the detected error so the motor normally runs
> > dead cool, much more energy efficient than std 2 phase steppers. This is
> > the power that spins the electrical meter determining your monthly power
> > bill. The error, if only 1 count between the step-gen count and the
> > encoder, feeds less than an amp to the motor, 2 count error, maybe an
> > amp, 10 counts, 4 amps. This is micron accuracy in most direct drive
> > situations.  Their speed limit is more likely to be determined by the
> > speed of the opto-isolators in the drive input circuitry. Testing these
> > motors just laying on the table with no load, I've run them with a
> > function generator at 375 kilohertz! At a /8 microstep, that's over 3000
> > revs at 24 volts. At 90 volts, it might be possible to hit the 5000 revs
> > and still have usable torque to turn the load.
> >
> > It might take another box to contain the psu and driver, but I think the
> > motor itself is capable to doing the job. Wired into hal correctly, a 5
> > micron error will stop linuxcnc in a millisecond. Tested, works, but has
> > yet to occur doing a job. Currently the driver costs more than the
> > motor, but I suspect that will equalize and lower once the NRE costs
> > have been recovered, say about a year from now.
> >
> > Bleeding edge tech usually has a bleeding edge price... TANSTAAFL.
> >
> > >> On Apr 25, 2023, at 7:00 AM, Todd Zuercher 
> > wrote:
> > >>
> > >> I'm a little confused, a BLDC motor is still going to need a
> > drive/driver, weather or not it runs at line voltage, that you say you
> > don't have space for.  How is that going to help you?
> > >>
> > >> Todd Zuercher
> > >> P. Graham Dunn Inc.
> > >> 630 Henry Street
> > >> Dalton, Ohio 44618
> > >> Phone:  (330)828-2105ext. 2031
> > >>
> > >> -Original Message-
> > >> From: Thaddeus Waldner 
> > >> Sent: Monday, April 24, 2023 5:40 PM
> > >> To: Enhanced Machine Controller (EMC) <
> emc-users@lists.sourceforge.net>
> > >> Subject: [Emc-users] Medium voltage BLDC motor
> > >>
> > >> 

[Emc-users] OT: Air cooled router spindle problem

[Roland Jollivet]

A break in one of the wires would cause it be on two phases, vibrate and
not run. Definitely intermittent as it flexes. A piece of cable is so cheap
compared to another VFD. Just strap another cable onto the cable chain and
run it for a few hours.
If it doesn't fail, it's not conclusive, but if it does, then you know for
certain it's the VFD.

Cables that flex are a consumable, unless it's very high quality Lapp cable
or other.

Roland


On Fri, 17 Mar 2023 at 02:50, Leonardo Marsaglia 
wrote:

> Hi Gene,
>
> Well, it's a little tricky because of the amount of cables I have running
> next to the ones of the spindle. But I checked the integrity of the cable
> and by visual inspection it all looks alright. It's a 3 wire cable with the
> black insulating cover so it's pretty well protected.
>
> I really doubt the cable is the problem from what I've experienced and from
> the condition of the cable in general.
>
> El jue., 16 de marzo de 2023 16:52, gene heskett 
> escribió:
>
> > On 3/16/23 12:44, Leonardo Marsaglia wrote:
> > > I've checked that the terminals are connected well but I didn't check
> for
> > > the entire cable to be alright.
> > >
> > > I thought about it but I really didn't think such an intermittent
> failure
> > > could be caused by the cable alone. Do you recommend to install a new
> > cable
> > > just in case?
> > >
> > That depends on how old that cable is, and how much flexing it has
> > endured in its time.  And in some instances, what color the plastic used
> > for insulation is. Magenta, aka hot red or hot pink, contains a chemical
> > I can't name but it destroys the copper in the wire by converting it to
> > a fine, rust colored powder that may, or may not, properly conduct
> > electricity. That color is most often found in two-way radio microphone
> > cords as the connection to the tx button, or today, more commonly as the
> > outer jacket of a sata drive cable in your computers.  In either case,
> > the failure rate by the time its 5 years old, is well up the far end of
> > the well known bathtub curve. I long ago changed all of mine out for any
> > color but hot red/aka magenta.  End of drive errors.
> >
> > I have serious doubts that is the problem in this case, since the
> > currents involved are definitely capable of starting a noticeable fire.
> > But a hand, run along the length of the cable, looking for hot spots
> > when the failure is in evidence might not be a bad idea. Or better yet,
> > tracing the wire with an IR thermometer or infra-red camera.
> >
> > > El jue., 16 de marzo de 2023 13:37, Todd Zuercher <
> to...@pgrahamdunn.com
> > >
> > > escribió:
> > >
> > >> Have you checked your cabling between the motor and VFD?
> >
> > And please folks, take a break on the mail server, and trim your posts
> > down to the context of your reply.
> > Cheers, Gene Heskett.
> > --
> > "There are four boxes to be used in defense of liberty:
> >   soap, ballot, jury, and ammo. Please use in that order."
> > -Ed Howdershelt (Author, 1940)
> > If we desire respect for the law, we must first make the law respectable.
> >   - Louis D. Brandeis
> > Genes Web page 
> >
> >
> >
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[Emc-users] Linuxcnc HAL and AI

[Roland Jollivet]

Since most ?? of us have some difficulty with configuring the HAL script, I
thought maybe ChatGPT could help.

So this is obviously very generic, but one can easily 'add' new
parameters/constraints to the query. By the way, I have no clue if it is
correct or not.

Maybe someone could try troubleshooting their existing script by pasting it
into AI and ask to check it.

Another option is for a developer to write a web page interface using the
AI API to help users generate HAL scripts.
_

AI  Q: write a HAL script for Linuxcnc using steppers and a 7i92 interface
card

AI  A: Here is an example of a HAL script for LinuxCNC using stepper motors
and a 7i92 interface card:

# Load the 7i92 driver
loadusr -W hal_7i92 -i0

# Declare the step and direction pins for each axis
setp stepgen.0.step_pinhalui.0.axis.0.step
setp stepgen.0.dir_pin halui.0.axis.0.dir
setp stepgen.0.enable_pin  halui.0.axis.0.enable

setp stepgen.1.step_pinhalui.0.axis.1.step
setp stepgen.1.dir_pin halui.0.axis.1.dir
setp stepgen.1.enable_pin  halui.0.axis.1.enable

# Set the maximum frequency for each axis
setp stepgen.0.maxvel  1000
setp stepgen.1.maxvel  1000

# Connect stepgen outputs to 7i92 step and direction pins
net step0-out stepgen.0.step=> 7i92.0.step-0-out
net dir0-out stepgen.0.dir  => 7i92.0.dir-0-out

net step1-out stepgen.1.step=> 7i92.0.step-1-out
net dir1-out stepgen.1.dir  => 7i92.0.dir-1-out

# Enable the stepper motors
setp halui.0.axis.0.enable 1
setp halui.0.axis.1.enable 1

This script assumes that you have already set up the hardware connections
between your 7i92 card and stepper motors, and configured the 7i92 for use
with LinuxCNC. Note that you may need to modify the pin assignments and
other parameters based on your specific setup.

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[Emc-users] custom m codes tutorial and cnc lathe bar pulling

[Roland Jollivet]

I do like the 'bar pusher' as opposed to a puller...

https://www.youtube.com/watch?v=1vumk-ZvnjU

Roland


On Sun, 29 Jan 2023 at 12:21, andrew beck  wrote:

> Thanks gene
>
> Hey you might know how to loop a gcode file
>
> I want to loop a gcode file 50 times.
>
> Ideally using m98 and m99
> But I'm a bit stuck on how to do it.
>
> Does anyone have some tips?
>
> This is for bar pulling in CNC lathe
>
> M400 unclamps chuck and m401 clamps chuck
>
>
> And I need some way to loop the g code
>
> On Fri, 27 Jan 2023, 15:12 gene heskett,  wrote:
>
> > On 1/26/23 16:42, andrew beck wrote:
> > > hey guys
> > >
> > > just wanted to let people know i just made a tutorial on custom m codes
> > and
> > > i couldn't find much info on it and wanted to help the next guy and
> > remind
> > > myself when i forget next time lol
> > >
> > >
> >
> https://forum.linuxcnc.org/10-advanced-configuration/48071-custom-m-codes-and-bar-puller-set-up#262959
> > >
> > >
> > > and also if any of you machinists have good tips for bar pulling on a
> cnc
> > > lathe i would love the ideas i have never done it before
> > >
> > > regards
> > >
> > > Andrew
> > >
> >
> > I don't have a bar puller, not even a 5C collet, just an ER42 collet
> > kit. If I am doing multiple copies, I position the tool to act as a
> > stopper, loosen the big nut and push the rod thru to touch the tool,
> > tightening the nut again gets me a couple thou clearance but that can be
> > compensated for in your program. With a reasonable speed of bar pusher
> > so it does not damage the tool when it hits the tool, it ought to work
> > till you are out of that bar.
> >
> > One could put a microswitch in the position of the tool to automate
> > that, including a shutdown when the bar no longer trips the switch in a
> > long enough time it should have tripped.
> >
> > With a couple solenoids to engage the nut wrench, and a reversible vfd,
> > that all could be programmed. Even to ejecting the bars remains and
> > feeding a new one from a rack of them could be done.
> >
> > Lots of ways to skin that cat. This is just three ideas.
> >
> > Take care and stay well, Andrew.
> >
> > Cheers, Gene Heskett.
> > --
> > "There are four boxes to be used in defense of liberty:
> >   soap, ballot, jury, and ammo. Please use in that order."
> > -Ed Howdershelt (Author, 1940)
> > If we desire respect for the law, we must first make the law respectable.
> >   - Louis D. Brandeis
> > Genes Web page 
> >
> >
> >
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>
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[Emc-users] OT: Shapr3D

[Roland Jollivet]

I wondered if anyone is using this package...
I've just become aware of it.

Free with limited functionality, or $25/m paid..

https://www.youtube.com/watch?v=oCo90ILLX5U

https://www.shapr3d.com/pricing

Roland

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[Emc-users] Fusion 360

[Roland Jollivet]

I've tried F360 for code on a small lathe and find it quite painful to get
the toolpath usable. It often wants to part off before completing the turn,
or just doesn't machine optimally.
Possibly because I mostly machine with a grooving tool, so you don't need a
tool-change.

I have to mess with the stock parameters etc. until it's a semblance of
usable, then re-arrange snippets of code to get the code usable.
What's really painful on Fusion is that you have to enter, and exit
'simulation', so you can never just make a small adjustment and see the
effect on toolpath.

Maybe I'm doing it wrong, and can't find a decent video on F360 lathe
turning. Have you come across one?

Roland



On Wed, 2 Nov 2022 at 11:47, stjohn gold  wrote:

> Fusion360 is great for cnc lathe work and post processor modification is
> perfectly possible. I always use a space mouse and a normal mouse for
> cad/cam work. I tried with a few different cad/cam systems running in a vm
> etc and gave up. You will always get best results to my knowledge running
> in windows ie what OS the said system is most used in, tested, developed
> and supported in by the company that makes it. Community support for
> fusion360 is reasonable for most stuff. I bought a license specifically for
> the lathe cam. So far I am fairly happy. It solved a problem for me.
>
> cheers!
> st.john
>
> On Mon, 24 Oct 2022 at 11:13, Viesturs Lācis 
> wrote:
>
> > sestd., 2022. g. 22. okt., plkst. 12:59 — lietotājs andy pugh
> > () rakstīja:
> > >
> > > I also have, and strongly recommend, a Space Mouse:
> > >
> >
> > Awww yisss, +1 on this one! I have the very first gen SpacePilot, got
> > it almost for free (it is not officially supported any more, it is
> > trickery to get it recognized and everything installed  when I change
> > PC, but the device itself works like a charm) and it makes
> > pan/zoom/rotate so much easier! Especially in assemblies when placing
> > mates and the model has to be moved and rotated constantly to select
> > proper faces/edges etc.
> >
> > Viesturs
> >
> >
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[Emc-users] OT How to make fine splines

[Roland Jollivet]

Maybe this G156 could be implemented in Lcnc..

https://www.youtube.com/watch?v=N_tozv1szIo

It's great, but also limited in that you need a broaching tool the width of
the broach.
One should be able to broach a 4mm slot with say, a 3mm width tip





On Tue, 25 Oct 2022 at 10:45, andy pugh  wrote:

> On Tue, 25 Oct 2022 at 09:31, Roland Jollivet 
> wrote:
> >
> > If you have a CNC lathe, you could do this;
> >
> > https://www.youtube.com/watch?v=TW6QPl8Oy7g
>
> It could be done with a mill too, with a non-rotating fixture on the
> head. But that still needs a run-out at the shoulder.
>
> --
> atp
> "A motorcycle is a bicycle with a pandemonium attachment and is
> designed for the especial use of mechanical geniuses, daredevils and
> lunatics."
> — George Fitch, Atlanta Constitution Newspaper, 1912
>
>
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[Emc-users] OT How to make fine splines

[Roland Jollivet]

If you have a CNC lathe, you could do this;

https://www.youtube.com/watch?v=TW6QPl8Oy7g



On Mon, 24 Oct 2022 at 16:32, John Figie  wrote:

> I have a 1978 Honda XL175 I want to get running again. The Kick start shaft
> is broken, a common problem on this bike. Replacements are hard to find and
> usually $400 or more. Maybe I can make a few and sell a few. I am wondering
> if I can use 4130 steel that is pre hardened to Rockwell C32 and has
> 135,000 psi tensile strength. Or maybe just take a grade 8 bolt and machine
> it. or maybe even a metric grade 12.9 bolt which should be even stronger.
> Anyway I am wondering how the splines were made on the original. I could
> use the E head, (shaper) on my bridgeport and a rotary table. Do you think
> this is a good idea?
>
> Shaft_Model 
> Spline 
> John Figie
>
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[Emc-users] stmbl servo drives - want to buy...

[Roland Jollivet]

> Now.  Why is it not available?  Two reasons.  The key thing about the
> STMBL for 3 phase AC servos was that it used single driver for all three
> windings.  Probably originally designed for washing machines.  It was
> discontinued.  A different one with slightly lower power was available.
> There are others but different pinout so board change.
>

Yes, the same style driver chip found in all the chinese drives too. A
27pin PDIP
I opened a Chinese drive up and it looked to be a text-book implementation
of one of these drivers. With very little noise suppression though.

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[Emc-users] Matrix Wiring

[Roland Jollivet]

You don't say how often you need to change the jumpers, or how compact you
need this to be, or how easily they need to be changed.

But, if you have two pcbs that you can move far apart, then load one side
with pins, then bring them together, you could use something like this;
https://www.harwin.com/products/P70-2300045R/

There are many styles and brands of these 'test pins'

Roland



On Tue, 12 Jul 2022 at 11:44, andy pugh  wrote:

> Not CNC related, but I thought that someone here might know the answer.
>
> I want to make a rewirable adaptor (OBDII to DB15)
>
> One neat way to do this would be with a matrix, where you plug something
> into holes and that connects the row to the column.
>
> As a CNC link (almost) I think that something like this was used on the MEC
> Microsprint programmable lathes where things often called "diodes" were
> plugged into holes to program the machine.
>
> I feel that a couple of PCBs. spaced a small distance apart, could have
> plated-through holes linked by "something" being plugged through them. The
> problem being to find the "something" that will make contact with two holes
> at the same time.
>
> A single PCB and an array of jumpers would work, but that would be 480 pins
> to keep track of
>
> The plated-hole idea has 240 holes, but only needs 8 plugs to do the
> programming I need.
>
> 2mm banana plugs do exist.
> https://uk.rs-online.com/web/p/banana-connectors/7632907
>
> But I am not sure if they will reliably connect two plated holes.
>
> --
> atp
> "A motorcycle is a bicycle with a pandemonium attachment and is designed
> for the especial use of mechanical geniuses, daredevils and lunatics."
> — George Fitch, Atlanta Constitution Newspaper, 1912
>
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[Emc-users] Clausing NC Spindle drive belt tension and noise.

[Roland Jollivet]

If the noise is from the belt whipping, then lightly press a rod, or two,
on the back of the belt to see the effect on the noise. Be careful...
So if it helps, you could add two 50mm bearinged idlers on the outside of
the belt. Maybe use those two holes I see to mount.


On Sun, 3 Jul 2022 at 22:23, John Figie  wrote:

> I am back to making slow forward progress on the Clausing NC since
> putting on hold back in March. The lathe came with the 5HP motor
> already mounted and I have kept this as is from the previous owner
> that gave up on the retrofit.  The original lathe had a mechanical
> variable speed drive with pulleys similar to that on a bridgeport
> variable speed head. I have mounted and wired up a Huanyang 7.5 Kw VFD
> for the motor and first ran the motor today. I am using a 7.5Kw
> inverter to allow for derating for single phase per Huanyang
> recommendations.
>
> I have about 1" of deflection in the belt. The belt seems quite noisy
> when running the motor at 1725 RPM. I have not yet attempted to run
> the motor at 3200 RPM which is my goal to get 2000 RPM spindle.
>
> Are these kinds of timing belts usually noisy?
> The original clausing manual says have 1" of belt deflection - but
> they don't specify a force. Also the original timing belt was probably
> about 3/4 as long as the one I have now because of the way the
> variable speed drive was mounted. There isn't much clearance between
> the belt and the z axis motor like 1/4" but increasing that clearance
> would make less clearance to the spindle drive encoder (not mounted at
> the moment).
>
> https://photos.app.goo.gl/hSYW84zZsdnoKdr79
>
> Motor running at approx 1725 RPM
> https://photos.app.goo.gl/FxjZn6QRmztM1TQk8
>
> John Figie
>
>
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[Emc-users] spindle problem

[Roland Jollivet]

Presumably your machine is different to mine..
I have a BT30 spindle and it had broken washers when I got the machine.

I was very relieved to simply loosen/remove two locking nuts at the top of
the drawbar and the complete stack simply dropped out the bottom.


On Mon, 27 Jun 2022 at 18:04, dave engvall  wrote:

> Hi Todd and others;
> Indeed it is a horrible idea but I feel backed to the wall.
>
> I have T lugs but they are secured by M6 shcs which is no where close to
> as strong as the normal retention stud. However, I plan to use the
> machine at full rpm with AlCrN coated end mill,
> coolant and keep the loading low.
> I don't have much to lose. My chances of living more than 10 years more
> are not good and that assume health good enough to work in the shop.
>
> Dave
>
>
> On 6/27/22 7:25 AM, Todd Zuercher wrote:
> > Gluing a spindle taper into a spindle sounds like a truly horribly
> idea.  (I'd be more worried about it letting go when you didn't want it to,
> than trying to get it out later if you did want to remove it, although that
> also may prove problematic.)
> >
> > The drive lugs are usually removable/replaceable.  Maybe you could make
> new drive lugs that also positively engage the tool holder to retain it.
> Something like a longer T shape that would capture the tool holder flange.
> (Personally I'd do every thing I could to fix the spindle properly though.)
> >
> > Todd Zuercher
> > P. Graham Dunn Inc.
> > 630 Henry Street
> > Dalton, Ohio 44618
> > Phone:  (330)828-2105ext. 2031
> >
> > -Original Message-
> > From: dave engvall 
> > Sent: Monday, June 27, 2022 9:57 AM
> > To: emc-users@lists.sourceforge.net
> > Subject: Re: [Emc-users] spindle problem
> >
> > [EXTERNAL EMAIL] Be sure links are safe.
> >
> > Update: The drive lugs get in the way of a safety disk or ring or
> anything else. Epoxy looks more promising; just a semi-permanent solution.
> > Note: Epoxy can always be removed with heat or chlorinated solvents
> but...
> > Dave
> >
> > On 6/27/22 6:27 AM, dave engvall wrote:
> >> Back again;
> >> Since crawling in under the spindle is difficult for an old stiff guy
> >> I laid the iphone on the table and took a pic, rotated the spindle 45
> >> degrees and took another; nothing useful moved. However, there are
> >> large socket head cap screws around the perimeter of the spindle. It
> >> should be possible to make a safety cap that has a few thou clearance
> >> to limit axial movement. 'Maybe' I can jury rig something. Basically I
> >> have to see what kind of clearances I have. An actual thrust bearing
> >> seems like asking for trouble.
> >> Psychologically it would almost be easier to pick up the radiator cap
> >> and run a new(er) one in. Still that brings all sorts of problems of
> >> its own. Hard to win.
> >> Back to the drawing table. ;-)
> >> Dave
> >>
> >> On 6/26/22 9:10 AM, andy pugh wrote:
> >>> On Sun, 26 Jun 2022 at 15:45, dave engvall 
> wrote:
> >>>
>  A couple of solutions present themselves but neither are ideal.
>  Simply use the M6 shcs that hold the dogs in place to secure the
> CAT40.
>  Balance and adequate strength/safety would seem to present problems.
> >>> Does the nose have any extra holes? There are 4 threaded holes with
> >>> no obvious function on my 30INT spindle and looking around the
> >>> internet I see threaded holes in some of the CAT40 spindles.
> >>> It seems that you could use those to hold in a custom ER40 (or
> >>> similar) adaptor.
> >>>
> >>> 4000 rpm probably isn't fast enough to need to worry too much about
> >>> balance.
> >>>
> >>>
> >>
> >>
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> >
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[Emc-users] spindle problem

[Roland Jollivet]

Surely you could hire a buff mechanic from down the road and totally
supervise/instruct him what to do?


On Sun, 26 Jun 2022 at 16:45, dave engvall  wrote:

> Hi,
> My Mazak V5 has been down for a few years. First for brushes on the
> spindle motor and then a much more serious broken belleville stack.
> Unfortunately, the spindle on this model comes out from the top which
> means pulling all the hydraulics and the spindle motor/transmission and
> getting them out of the way. I don't see that is it possible to replace
> the stack w/o fussing with all of the above.
> Note: I'm 4 score and 4 and not as energetic as I used to be.
> A couple of solutions present themselves but neither are ideal.
> Simply use the M6 shcs that hold the dogs in place to secure the CAT40.
> Balance and adequate strength/safety would seem to present problems.
> The other solution is to simple punt and epoxy a CAT40 in place and live
> with the restrictions.
> Candidate CAT40 is a SK16 with holders for end mills up to M16 and at
> least consider adding an ER20//ER16 with a M16 stub (custom dia) to
> drill/ream. I have sets of ER20 and ER16 collets.
> Note: spindle is 4000 rpm and 5 HP geared.
>
> If anyone has a better idea I'm all ears.
> As usual TIA: I seem to be out of easy/ideal solutions.
>
> Dave
>
>
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[Emc-users] Hight Frequency VFD

[Roland Jollivet]

> The drive had been acting up for the past couple months.  When the machine
> would be first powered on (throwing disconnect) the drive would not "turn
> on" right away "Power" LED on the front of the drive would not light up,
> even though the drive had power on all 3 phases.  If the machine was left
> turned on for an extended period of time (a half hour or maybe more)
> eventually the drive would power up and work correctly.  This drive has no
> display other than a row of 5 LEDs for fault and power indication.  None of
> the alarm indicators have ever have shown anything.  Last week it stopped
> working completely.  We are of the opinion the problem probably likes in
> the low voltage board and won't be easily found.
>
> Todd Zuercher
> P. Graham Dunn Inc.
> 630 Henry Street
> Dalton, Ohio 44618
> Phone:  (330)828-2105ext. 2031
>

My guess is that it's a joint issue on the power side. Thermal cycling
causes the solder joints on power devices to eventually break contact. Once
the board warms up, contact is made again. (or vice versa)

As a start. I would open the drive and re-solder all the power devices, and
power connectors. I've done this often in the past that's saved a device.
(be careful to let the HV caps discharge over a few hours before opening.
There is normally a bleed resistor)

If there was a fault in the signal side, it wouldn't 'recover' as it did.

Roland

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[Emc-users] custom | stock bearing nut

[Roland Jollivet]

On Tue, 5 Apr 2022 at 18:47, dave engvall  wrote:

> Hi all,
> I have a pair of ball screws: THK KX 71227 A
> These are new but older and as far as I can tell not on the THK site.
> They are threaded on one end to retain a bearing.
> M15 x 0.8 or close. Does anyone know of a bearing nut that would fit or
> am I stuck with
> having a pair custom made?
> I've spent a fair amount of time searching the web but maybe (probably)
> someone else's  google foo is better than mine.
> As always TIA
>
> Dave
>

0.8mm pitch is very... fine for a diameter that large. Unlikely.
It's possibly 1mm as that is the finest most large diameters go to.

So the easiest way to check is to take a machine screw and lay it on the
ballscrew to check engagement, with a standard;
M8 x 1.25mm
M6 x 1mm
M5 x 0.8mm
M4 x 0.7mm

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[Emc-users] Graceful pi shutdown, power off

[Roland Jollivet]

On Wed, 16 Feb 2022 at 16:17, Thaddeus Waldner  wrote:

> > Just use a simple 10A relay with 5V coil
> > As a latch, you press a button to power up, ie power the coil, then the
> > same line gets dropped by the Pi to power off..
>
> How does the pi drop the 5v line after shutting down?


The circuit can be similar to attached..
But I've got no idea if there are 'hooks' in Linux so you could add code to
drop the relay at the end-of-shutdown.
Or whether you can get Linux to pull in the relay on power-up

I presume this has to be in Linux, not LinuxCNC.
Ok, I did a quick search and found this;
https://stackoverflow.com/questions/45128655/where-does-acpi-hook-into-the-shutdown-sequence-on-linux-to-soft-off-the-pc

Roland
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[Emc-users] Graceful pi shutdown, power off

[Roland Jollivet]

Just use a simple 10A relay with 5V coil
As a latch, you press a button to power up, ie power the coil, then the
same line gets dropped by the Pi to power off..

https://www.digikey.co.za/en/products/detail/omron-electronics-inc-emc-div/G5Q-1A4-DC5/1815721


On Wed, 16 Feb 2022 at 00:00, Thaddeus Waldner  wrote:

>
> > Youu need a human to somehow
> > kick-start the process.  But it should be automated after that.  Of
> course
> > the computer *can* turn itself off.
> >
> > I've managed to put the "on" button on a phone or indoor PC.
> >
> …
>
> This is the part that won’t work. The machine is small enough to pick up
> and carry off. It will be used in a construction environment without
> dependable wifi. It will have multiple users. I think it should have a
> power button or switch.
>
> Thanks for the idea anyway… I’ve seen those smart plugs but it didn’t
> occur to me to have a computer operate them.
>
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[Emc-users] miniature taper-lock type pulleys

[Roland Jollivet]

On Thu, 27 Jan 2022 at 06:49, Ralph Stirling 
wrote:

> I had some problems today with a small XL timing
> pulley slipping on a NEMA17 stepper shaft due to
> the set screw loosening after running for long
> periods (multiple days).  I drilled and tapped a
> second set screw hole, and I can probably apply
> some thread locker, but I got to wondering if it
> would be possible to make a miniature taper lock
> type bushing and pulley to clamp onto a stepper
> shaft.  Anybody ever seen anything like that?
>
> The original taper lock system has a split bushing
> with an 8 degree taper against the pulley.  They
> also have a clever set screw arrangement to tighten
> the pieces together and to jack them apart when
> removing.  If you haven't used them before, a video
> is the best way to understand them:
> https://www.youtube.com/watch?v=-3K_vf_7fhM
>
> I like to 3d print my timing pulley perimeters, but
> a metal hub is nice (as has been discussed on here
> in the past).  I'm pondering how I could make hybrid
> pulleys with a taper locking hub.  Threading the holes
> in the plastic pulley wouldn't work so well.  Perhaps
> some threaded metal insert can be incorporated from
> the back side.
>
> Enough of my musings.  Looking forward to hearing
> other ideas and suggestions.
>
> -- Ralph


If you're 3D printing a larger pulley, you could do something as in the pic.
You drive a self-tapper into the small hole on the left to clamp the
flexure.
Add more screws/holes as needed.

Roland
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[Emc-users] ER-32 Collet Wrench

[Roland Jollivet]

On Wed, 12 Jan 2022 at 14:43, Stuart Stevenson  wrote:

> The length of the handle is purposely short as most people will use way too
> much torque to tighten the lock nut. Exceeding the chuck manufacturer's
> torque specification will not help in the holding capability and will
> result in less accuracy of the resulting assembly. Over torquing the
> assembly will begin to damage the components. The interface between the nut
> and the collet will usually show damage first.
> Just my 2 cents
> Stuart
>
>
That's fine, but when loosening a nut, a dual handle just feels so much
more stable and controllable when you have.those ultra sharp edges looking
back at you.
The actual torquing should obviously be done with competency..

Roland

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[Emc-users] ER-32 Collet Wrench

[Roland Jollivet]

On Wed, 12 Jan 2022 at 10:50, John Dammeyer  wrote:

> So my Collet chuck arrived a week or so ago.  Today the ER-32 collet set
> arrived.  I no longer have an excuse for not completing my 4th axis driven
> by a real harmonic drive.  (Well it is raining and can't cast).  So I have
> drawn up the face plate adaptor and that looks to be a pretty easy LCNC
> project for the mill plus a bit of lathe work.
>
> However, I foolishly did not order a collet wrench.  This seems to overall
> be a pretty easy CNC project with the exception of the 'teeth' that engage
> the collet.  I suppose I could mill out the profiles in some oil hardening
> steel, then file the teeth to have straight edges.  Finally harden it.
>
> Alternatively make it out of 1/4" or so steel plate (or even aluminium)
> and drill and tap holes for screws to protrude out where the teeth are.
> Turn down the screw ends to be smooth or even square and lock the screws in
> place.
>
> Looking for suggestions here.  Don't really want to wait 2 months for one
> wrench with either low price and horrendous shipping or high price and low
> shipping.  Cost ends up being the same at about $28.
>
> Thanks,
> John
>

I would suggest getting a handle laser cut.

If you mill it, or laser cut, put a recess at the internal corners so that
there is no finishing required. See exaggerated picture

Either way, make the handle double ended so you have greater control when
using it. Single handled tools are more likely to slip.
(can only be used when OD of cutter is less than nut, unless it's and open
type)

https://www.turnersupply.com/Product/129502242

https://www.ubuy.co.id/en/product/168WB1FKG-er40-wrench-cnc-collet-chuck-er-um-nut-spanner

Roland
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[Emc-users] Spindle positioning.

[Roland Jollivet]

You probably don't need more than 1 bar on the lifting air cylinder, up or
down. No need to force it down.
So let it down, then if you can give the spindle a 1RPM burst to let the
nut slip over.
And have a switch on driver Z to know if it's down over the nut.

You could also stop the spindle and descend the driver as the spindle
reaches it's last 5RPM? before stopping.

Roland



On Mon, 22 Nov 2021 at 10:03, John Dammeyer  wrote:

>
> > From: dave engvall [mailto:dengv...@charter.net]
> > On 11/21/21 9:24 PM, John Dammeyer wrote:
> > > Is there a way to tell the spindle to turn until it finds the index
> and stop so it's always stopping at the exact same spot?  Like
> > decelerate to 0.5 rev per second  (30 RPM) or slower and stop when the
> index happens?  With either an M5 or the button on the
> > user interface?
> > >
> > If I were� doing that� today I would use 3 sensors. IOW a guard sensor
> > either side of index, rotate quickly to detection of guard slow way down
> > and search for the central sensor. How you know which is the shortest
> > path is left as an exercise for the "student". ;-) Or maybe one simply
> > defaults to searching in one direction.
> >
> > If you don't need orientation then a stepper motor and a gear would seem
> > to be as simplistic as one can get.
> >
> > Dave
>
> One still has to line up the socket to the hex head of the drawbar.  And
> since it can be at any position relative to the spindle the sensing has to
> happen against the hex head.  Rotate spindle until hex head is at a known
> position.  Then rotate socket from and indexed position until it matches
> the socket and then send it down.  This could all happen in under 100mS and
> be almost transparent to an end user.
>
> There are times where I wish I had BMT-30 cone type tooling or just only
> TTS.
> John
>
>
>
>
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[Emc-users] Closed loop control of air motors.

[Roland Jollivet]

It's not what you asked, but what about a centrifugal clutch/limiter?
Above say 200RPM it could swing outwards and lock, only releasing again
once the torque is removed.



On Sun, 21 Nov 2021 at 09:45, John Dammeyer  wrote:

> Has anyone ever tried any sort of closed loop control of an air motor
> similar the one on this butterfly impact wrench.
> https://www.penntoolco.com/52-424-9/
> In order to not have both the TTS and R8 collet drop out of the spindle
> I'd like to be able to limit the number of turns to 2.
>
> What I've found however, is that 10mS pulses to the valve supplying air
> for CCW rotation barely move it until it's unloaded and then it immediately
> spins up very fast and does at least 4 to 8 turns.  That's way too many.
>
> I've only got a one pulse per rev hall sensor detecting a magnet on the
> socket.  But I suspect between reaction time of the valve, the
> compressibility of air and the rotary inertia of the motor that unless
> there is some sort of constant load that control is pretty well impossible.
>
> With servos, if the motor is loaded and then suddenly totally unloaded, it
> too might turn a number of revolutions before the control system could
> bring it back down to the original speed.
>
> Short of adding some sort of mechanical brake am I trying to do the
> impossible?  Oh and to avoid another 1000 words to explain I've added a
> picture.
> John
>
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[Emc-users] USB to Ethernet

[Roland Jollivet]

I might be wrong, but I'd think such a device would be resource heavy. Less
hardware means more gets done is software..



On Tue, 16 Nov 2021 at 09:21, John Dammeyer  wrote:

> Would this type of USB 3.0 to Ethernet work with Ethernet supported MESA
> boards?
> https://www.amazon.ca/dp/B00AQM8586?linkCode=gs2 <
> https://www.amazon.ca/dp/B00AQM8586?linkCode=gs2=hotoge0c-20>
> =hotoge0c-20
>
> John
>
>
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[Emc-users] Power Draw Bar

[Roland Jollivet]

On a BT30 spindle;
A button the front of the sindle, drawbar is depressed only as long as you
hold the button in.



On Sun, 14 Nov 2021 at 08:03, John Dammeyer  wrote:

> Quick question.
>
> On commercial machines that have buttons to load or unload the tool by
> actuating the drawbar how are the buttons arranged?
>
> Are there two?  One for Load and one for Unload?  Are they arranged
> vertically or horizontally?
>
> If vertically does the upper one load or unload?  If horizontally does the
> one on the right load or unload?
>
> Thanks
> John
>
>
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[Emc-users] Prox sensors and wiring

[Roland Jollivet]

I think the problem with proxies is that any chips in the probe path is
going to affect this distance, quite lilely flood coolant situations.

The mechanical switches on CNC machines however, have a slope on the switch
and are really difficult to press in with your finger.
This makes sure that any junk gets wiped off during the homing process.

As can be seen in this image, they often have two or three switches built
in;
https://za.pinterest.com/pin/531424824774161839/

This allows you to use actuating flags of different lengths to implement;
- axis home position
- overtravel limit
- Estop limit

Roland


On Thu, 4 Nov 2021 at 10:20, Chris Albertson 
wrote:

> I bought some of the proximity detectors for my 3D printer to measure the
> bed.I tested them on my mill by moving them untillthey tripped, backing
> off and doing it again to see how repeatable they are.Even the cheap
> no-=brand unit where as good as my ability to measure them.   Set up a test
> using a dial indicator.
>
> The absolute trip point was some random distance, all you care about is how
> repeatable they are.
>
> The one I liked is mounted in M12x1 threads.  I bought am M12x1 tap to make
> a mounting block
>
> The usual connector is called an "Aviation Plug".  they come in different
> diameters and with different amounts of pins.  The smaller size is enough
> for signals and the larger ones can handle motor current.They come in
> different quality levels too. The cheap Chinese ones are "good enough" but
> the American ones are precision made and have rubber gaskets.  Prices are
> about $3.50 for the cheap ones (on eBay or Amazon) and about $35 for the
> best quality ones (at Mc Master Carr and the like).
>
> The cheap plugs are made of something like chromed zinc and look cheap but
> work surprisingly well.   The best one are made of machined an
> green-primmered aluminum and have the quality you'd expect for an $80 per
> mating par part.   They are also sold with engineering-grade plastic
> housing
>
> On Wed, Nov 3, 2021 at 10:01 PM Ralph Stirling <
> ralph.stirl...@wallawalla.edu> wrote:
>
> > I have finally started stripping out the control cabinet on my cnc mill
> in
> > preparation for my retrofit.  The brushed servos and mechanical limit and
> > home switches were wired up with crimped "bullet" quick connect pins.
> I'm
> > replacing the servos with brushless servos, and am considering replacing
> > the mechanical switches with inductive prox sensors (pnp, nc type).  All
> > the old wires are sticky with coolant and metal chips.
> >
> > So, I am interested to hear what other lcnc retrofitters have found works
> > well for modest priced coolant proof connectors (3 or 4 pin), and
> opinions
> > on cheap Chinese prox sensors (since the name brand ones are so
> expensive,
> > even on ebay).  An example is:
> >
> https://www.ebay.com/itm/US-5Pcs-NC-PNP-LJ18A3-8-Z-AY-Inductive-Proximity-Sensor-Switch-DC6V-36V-/143861840692
> >
> > Photos (rather unorganized) of the retrofit are at:
> > https://photos.app.goo.gl/yBSRVf3QAVUK39PC7
> >
> > Thanks,
> > -- Ralph
> >
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> > https://lists.sourceforge.net/lists/listinfo/emc-users
> >
>
>
> --
>
> Chris Albertson
> Redondo Beach, California
>
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[Emc-users] Panasonic serial encoder interface

[Roland Jollivet]

I knew I had something on file...
Try this

;

Everyone should download it just for reference..

Roland


On Fri, 22 Oct 2021 at 06:49, Ralph Stirling 
wrote:

> We are digging into a 2002-vintage Denso 6-axis robot,
> with a Linuxcnc conversion in mind.  The joint motors
> on this robot appear to have Panasonic encoders with
> a four wire interface and a fair amount of circuitry
> inside each encoder.  I suspect that these are the same
> as the ones in this EEVblog thread:
>
>
> https://www.eevblog.com/forum/projects/interfaceprotocol-to-encoder-on-panasonic-servo-motor/
>
> A rather terse comment at the end of that thread
> suggests that these are 2.5Mbaud async RS485 communications:
>
>2.5MBps RZ 8N1 RS485
>0x52 comes from drive - seems encoder reset.
>changes afterwards to 0x2a - read encoder command
>
> We already determined that ours are using RS485, so this
> seems to confirm we are looking at right things.  Anybody
> ever tried interfacing such encoders to LCNC?
>
> Thanks,
> -- Ralph
>
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[Emc-users] was; Shortening motor shafts, now account

[Roland Jollivet]

Hi Andy

I'm also on gmail and got this message. Never seen it before;

Roland
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[Emc-users] Replacing a handle.

[Roland Jollivet]

On Wed, 13 Oct 2021 at 05:36, John Dammeyer  wrote:

> This has nothing to do with LCNC specifically.  Really more a how to use
> LCNC.
>
> The attached picture is of a broken tripod crank handle that clearly was a
> casting.
>
> I can't figure out how I'd hold the raw stock to machine it.  The slot
> would be easy.  But the angles and tapers and curves go in three different
> dimensions.
>
> Maybe a stub on the end held in a 4th axis?
>
> Any suggestions are welcome.
> John
>

As you suggested, a stub.

If the handle is 100mm long, and your vice is 100mm wide,  I would use a
piece of bar stock 220mm long.

Justify the blank end flush at the vice far end, and mill the overhang,
then rotate.
Simply rotate axes in CAD to get 4 programs, or keep a model of the vice in
cad and do 4 assemblies.

Roland

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[Emc-users] splicing teeny wires

[Roland Jollivet]

Hi Gene

I don't know if you know about these splicers. Mostly used for telephone
wire. You can see what's going on, and any pliers will do the trick, but
they're not 'in-line'

https://www.amazon.com/Connector-Uvital-Waterproof-Gel-Filled-Connectors/dp/B07Z7NY6BN



On Fri, 20 Aug 2021 at 15:54, Gene Heskett  wrote:

> Greetings all;
>
> I am converting a Creatlity CR10-S Pro v2 3d printer to a 350C capable
> volcano version of the E3D V6 hot end.
>
> Which means I have quite a slew of stuff to splice, probably in that box
> of the left end of the X carriage. But generally, insulated splices have
> not shrunk in 65 years.
>
> I have one of those 4 jaw crimping tools that goes down to quite small
> stuff but I think its made for teeny gage bare tubing like Hilichi stuff
> and would probably pierce the jacket on this splice:
>
> <
> https://www.ebay.com/itm/390629743508?_trkparms=aid%3D1110002%26algo%3DSPLICE.SOI%26ao%3D1%26asc%3D233198%26meid%3D80b5051cdfab468899d391b72c2e417d%26pid%3D101196%26rk%3D3%26rkt%3D12%26sd%3D290952356482%26itm%3D390629743508%26pmt%3D1%26noa%3D0%26pg%3D2047675%26algv%3DPromotedSellersOtherItemsV2WithMLRv3&_trksid=p2047675.c101196.m2219=cksum%3A39062974350880b5051cdfab468899d391b72c2e417d%7Cenc%3AAQAGAAABACtrZQ7uyU6NyRWMuc0OogoSa%252FUIDys%252F02w7jR10vOAtqMWPMvUBy6zzURpE8MjiCMTi6DgxxzvpD7iVSzJu8kvcZJZt4or%252Fa0xNRt86VxZQtHfiTjHy6BuxnZxXAupqTuSeGfkfcGVmv1BN3DUXQpudR31aCwMHJdRFc4KK5umNoYX1Ip1n21fqZ7jd%252BVYvIrJuQIfgC98ZJV0GBU4TuPrvS1gwa%252BI11X3QC4%252FWTmwG0LllfLTLnPvFBZEO%252BSS9flJVcF92B%252FQCGx6tngkE0upULNQnwWhgdiAVwZF8jbFqfEnkhcoe8z6zcTb7J2Vx2HAtRivwV3%252FZjJ%252BBXO9NDkM%253D%7Campid%3APL_CLK%7Cclp%3A2047675=1751148278
> >
>
> So what crimp tool would serve to do a fine job of crimping that
> connector while leaving the insulation intact?
>
> If you know of an even smaller splice, and the tool for it, I'd sure
> appreciate being advised.
>
> Thank you.
>
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> If we desire respect for the law, we must first make the law respectable.
>  - Louis D. Brandeis
> Genes Web page 
>
>
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[Emc-users] Something went wrong.

[Roland Jollivet]

I would send the .dxf to the laser shop and collect the cut-and-bent parts
in a few days. Some parts are not worth machining when there's a far easier
practical solution.

Roland



On Tue, 3 Aug 2021 at 23:31, John Dammeyer  wrote:

> That's a good suggestion John F.  Thanks.  I did do some more playing
> around and it's clear the part flexing and the backlash both were at fault
> especially with the plunge to the next depth.
>
> And that brings up another issue.  One of my pet peeves with electronics
> project magazines is they are great at a schematic and either point to
> point wired or PC board but very little energy is spent on describing
> various ways of mounting or installing in a cabinet.  Especially with the
> concept of Human Factor Engineering which is the practice of making
> something easy to use or even intuitive.  Like an ESTOP button is always a
> red mushroom  Not a toggle switch.
>
> Same goes with work holding.  Youtube has tons of videos that show a
> tiring sequence of a milling cutter sprayed with coolant making chips for 3
> minutes with 3 commercials interjected, one every minute.   But very little
> on work holding.
>
> The next part I am making is shown in the attached screen shot rendering.
> My raw material is in the second photo.  So the question is about work
> holding and how or what features of LinuxCNC can be used to make this
> easier.
>
> I can use my band saw to create the initial width and split it into two L
> shapes.  But after that I start to have problems, due to lack of experience
> I think, on how to firmly hold it and mill the stuff with a 5mm and  6.35mm
> (1/4") cutter.
>
> Suggestions?
>
> Thanks
> John
>
>
> > -Original Message-
> > From: John Figie [mailto:zephyr9...@gmail.com]
> > Sent: August-03-21 11:59 AM
> > To: Enhanced Machine Controller (EMC)
> > Subject: Re: [Emc-users] Something went wrong.
> >
> > Speaking of backlash. My tiered old Bridgeport has about 0.002" of
> backlash
> > in the ballscrews. So if circular interpolation is used there is a small
> > bump at each 90 degrees of the circle. But if I make the finish pass
> first
> > clockwise and then repeat counter clockwise the imperfections are much
> > smaller. I know from experience with my first CNC machine that's built
> that
> > actually used leadscrews with lots of backlash the clockwise followed by
> > counter clockwise method was remarkable compared to a single direction
> > final pass.
> >
> > John
> >
> > On Tue, Aug 3, 2021, 10:10 AM jrmitchellj  wrote:
> >
> > > You might try the run again without the backlash compensation in LCNC
> to
> > > get a feel of what it is actually doing.
> > >
> > >
> > > --J. Ray Mitchell Jr.
> > >
> > >
> > > �I predict future happiness for Americans, if they can prevent the
> > > government from wasting the labors of the people under the pretense of
> > > taking care of them.�
> > >
> > > THOMAS JEFFERSON
> > >
>

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[Emc-users] Ethercat returning message disappear

[Roland Jollivet]

No I don't but you might find this interesting. It was in an email I got
two days ago.
The software is downloadable;

https://www.st.com/en/evaluation-tools/steval-eth001v1.html?ecmp=tt21493_gl_enews_jun2021=stmDM44500=438016236=mrX5prLpL0WLPr+vcjBGHEiEOnoACPSG9a4XfANkxEI=



On Sun, 11 Jul 2021 at 16:37, Nicklas SB Karlsson  wrote:

> Experimenting with Ethercat.
>
> Connecting three devices it work perfect. But with more there are cases
> then only some messages arrive back to master and some cases there no
> messages arrive back to master. Even though message do not arrive back
> as expected checking with broadcast write message arrive at last device
> and probing with oscilloscope I could see data is sent on Ethernet cable
> back towards computer. No sign of other communication problems except
> what I am pretty sure is ordinary Ethernet messages destroyed on purpose
> by nodes.
>
> Anyone else here have any experience with Ethercat?
>
>
> Nicklas Karlsson
>
>
>
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[Emc-users] Machining question

[Roland Jollivet]

I've worked with Fanuc robots,and was amazed to find that none of the
cables were shielded. The robot, with motors and encoders, is linked to the
control box with a 6m cable. All unshielded. Ok, the power and signal
cables are separate, but once installed, all extra cable is looped together
next to the control box.

A while back I stripped some Motoman robots. Internal on the arm, all the
motor wires, and encoder wires, are tightly bundled together. No shielding
on either.





On Mon, 21 Jun 2021 at 22:15, Thaddeus Waldner  wrote:

>
> Okuma machine builders really don’t like quantization noise so they use 40
> million CPR encoders on the axis motors.
>
> > On Jun 21, 2021, at 11:34 AM, Chris Albertson 
> wrote:
> >
> > Quantization noise is fundamental and present in all digital systems.
> > There is absolutely no way to avoid it.  All you can do is minimize it.
> >
> > To know how fast a shaft is spinning or how far it moves, you have to
> count
> > edges and if you get 100 counts you just can not know if you are closer
> to
> > 100 or to 101 counts.  Basically the counter always rounds down even if
> at
> > 100.9 it tells you "100".So the cound is "wrong" 50% of the time.
> > This applies not only to encoders, but A/D converts and every other kind
> of
> > measurement.
> >
> > This is the nature of digital data, of representing the world  with a
> fixed
> > number of bits.
> >
> >> On Sat, Jun 19, 2021 at 4:00 PM John Dammeyer 
> >> wrote:
> >>
> >> But doesn't the 7i92 FPGA deal with quadrature encoders and therefore
> >> doesn't really need to deal with a sampling process but instead looks at
> >> edges?  And because of the way quadrature works, with the A/B phasing
> you
> >> don't get the same types of errors compared to polling a bit level X
> times
> >> per second and trying to decide when it's high/low.
> >>
> >> John
> >>
> >>
> >>> -Original Message-
> >>> From: Chris Albertson [mailto:albertson.ch...@gmail.com]
> >>> Sent: June-19-21 3:21 PM
> >>> To: Enhanced Machine Controller (EMC)
> >>> Subject: Re: [Emc-users] Machining question
> >>>
> >>> There are two kinds of noise,
> >>> 1) electrical noise superimposed on the signal.
> >>> 2) quantization noise from the sampling process.  What happens here is
> >> that
> >>> the computer counts the number of line crossings during a given time.
> it
> >>> is just random luck when the time starts so on average there is a plus
> or
> >>> minus one count error.
> >>>
> >>> So a one count error sounds small but lets say we have a 600 count
> >>> encoder and we are running at 500 RPM and sampling 100 times per
> second.
> >>> This works out to 50 counts per period.  a one count error is a 2%
> >> error.
> >>>   You will see a larger percent error at slower speeds or with a lower
> >>> resolution encoder.
> >>>
> >>> So even with perfect wires and perfect grounding and zero electrical
> >> noise
> >>> the RPM speed is going to jump around randomly over a 4 RPM range
> because
> >>> of unavoidable quantization error.
> >>>
> >>> The solutions either the use a larger sample time apply a low-pass
> >> DIGITAL
> >>> filter to the signal.  No amount of analog filters on the wires will
> >> work.
> >>>
> >>> On Sat, Jun 19, 2021 at 2:55 PM Gene Heskett 
> >> wrote:
> >>>
>  On Saturday 19 June 2021 12:59:19 John Dammeyer wrote:
> 
> > I need to do a couple of things.  For one the AC Servo makes a lot of
> > electrical noise.  The frame of the motor is connected to earth
> > through power line ground.  But my bench setup has the control side
> >> 5V
> > not isolated from the 'PC' side (optos are kind of useless here) and
> > although the Pi4 doesn't appear to have any trouble the scope shows a
> > pretty noisy encoder signal.
> 
>  You are about to learn the star ground system I think.
> 
>  Thats where all grounds go to a single bolt, and no other grounds are
>  allowed anyplace.
> 
>  Shielding in motor cables ends without touching the motor, only
> >> connected
>  to this same single bolt which is grounded. The common line of any
> >> power
>  supply is connected only to this bolt, and the common grounds to every
>  piece of pcb in the system comes from that bolt. The used to be green
>  static ground wire in any power cord is rerouted to this bolt. And
>  static grounds on a power supply are fed from this single bolt.
> Because
>  the psu case is usually bolted down wherever its at, you may have to
>  uncover the supply and remove any connection from the earth labeled
>  terminal, and the psu's case. It may be a screw in the corner of a
> pcb,
>  but it needs to be removed.
> 
>  Anything connected to ground at some other point in addition to that
> >> bolt
>  becomes an antenna, is called a ground loop, picking up both magnetic
>  and electrostatic noises. I had to learn that the hard way while
>  building the Sheldon, 

[Emc-users] Running 440V 3PH 2 speed motor off 220V 3PH or 1PH?

[Roland Jollivet]

 On Fri, 18 Jun 2021 at 03:47, Gregg Eshelman via Emc-users <
emc-users@lists.sourceforge.net> wrote:

> Everything I've read on VFDs says do not feed them from a transformer.



But isn't every VFD on the planet fed by a transformer?
Many VMC and lathes have a 1:1 isolating transformer at the input to the
machine.


On Fri, 18 Jun 2021 at 03:47, Gregg Eshelman via Emc-users <
emc-users@lists.sourceforge.net> wrote:

> Everything I've read on VFDs says do not feed them from a transformer.

Nor can you put a transformer between the VFD and the motor. Most of them
> say *nothing* should be between the VFD and the motor, direct connection
> only. The one on my 1943 Monarch 12CK lathe recommends a noise filter on
> the input side to prevent noise feeding back into the line from the VFD
> from getting to other stuff on the circuit.
>
>
> On Thursday, June 17, 2021, 3:31:57 AM MDT, Peter Blodow <
> p.blo...@dreki.de> wrote:
>
>  Am 17.06.2021 um 07:20 schrieb Roland Jollivet:
> > ...
> > I don't know if you can use a 110V:24V transformer in reverse, or whether
> > you'll cook it. Worth a try...
> >
> > Roland
> NO!!!
>
> Peter
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[Emc-users] Running 440V 3PH 2 speed motor off 220V 3PH or 1PH?

[Roland Jollivet]

If you have some transformers lying around you could stack the secondaries
to get 440V
They don't need to be step-up, just sum the secondaries. You need to have
them all in phase obviously.

Then use a small, single phase 440V VFD
Most VFD's under 1Hp accept single or 3ph, but I don't know about 440V.
Maybe 380V

I don't know if you can use a 110V:24V transformer in reverse, or whether
you'll cook it. Worth a try...

Roland




On Tue, 15 Jun 2021 at 00:36, Gregg Eshelman via Emc-users <
emc-users@lists.sourceforge.net> wrote:

> The motor is in a Hardinge UM mill, less than 1 horsepower. It cannot be
> switched to 220V. Any way to get it running off 220 volts, three or single
> phase, without breaking a few banks?
>
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[Emc-users] Spindle Control

[Roland Jollivet]

On Tue, 15 Jun 2021 at 11:55, andy pugh  wrote:

> On Tue, 15 Jun 2021 at 10:33, Gregg Eshelman via Emc-users
>  wrote:
> >
> > Look up lost PLA casting.
>
> Though the drawback with that is that you only get one shot at it.
>

Which often makes me wonder why guys aren't CNC machining the moulds rather.
You'd have a simple CNC mill where the tool sticks directly upwards, and
use a dremel as a spindle.
Now you just 'machine' away the green sand until done.

You machine the cope and the drag in a similar way, including registration
features.

Roland

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[Emc-users] CUI devices

[Roland Jollivet]

Hi

I was wondering what experience people have had with the CUI encoders.

Mostly looking at the costs. The AMT13 series comes as a kit with all the
adapters, at $33
But it's supplied with no female connector. You might only realise this
when you open the box, after paying for shipping, duties and customs.

So you try finding a mating connector, and they're fairly obscure, but be
sure to order some pins too, otherwise you just get the plastic shell !

Alternatively buy a ready cable from CUI (Digikey) for your encoder at $25
!

It all sounds like a really shitty deal to me.
(a friends experience..)

Roland



https://www.digikey.com/en/products/detail/cui-devices/AMT132S-V/10269185?WT.z_cid=ref_neda_dkc_buynow_cuidevices_source=ecia_medium=aggregator_campaign=cuidevices

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Re: [Emc-users] OT: About a chat here on vacuum table ideas

[Roland Jollivet]

A friend was complaining about the need for 6kW vacuum system on a large
table and this got me thinking

Another way is to divide the table up into squares, grid wise, and have a
.. separate.. vacuum motor for each section. The motor is mounted under the
table at the bottom of each 'box'.
You can get ~1.5kW motors really cheap, and now it's easy to make up a
system with as many kW as you want.

Far easier to find 4 vacuum motors than a 6kW pump.

Roland



On Wed, 9 Jun 2021 at 17:13, Todd Zuercher  wrote:

> For milling sheet material on a large table, an MDF spoil board on top of
> a vacuum grid is usually the best option.  But for small parts such as
> solid wood items vacuum pods are usually a better choice.  In a pod
> arrangement with  the part held directly is where the valves are useful.
>
> Todd Zuercher
> P. Graham Dunn Inc.
> 630 Henry Street
> Dalton, Ohio 44618
> Phone:  (330)828-2105ext. 2031
>
> -Original Message-
> From: Leonardo Marsaglia 
> Sent: Tuesday, June 08, 2021 10:47 PM
> To: Enhanced Machine Controller (EMC) 
> Subject: Re: [Emc-users] OT: About a chat here on vacuum table ideas
>
> [EXTERNAL EMAIL] Be sure links are safe.
>
> Thank you guys for your answers!
>
> I've been reading and apparently MDF with a skim cut is pretty good to
> distribute the vacuum all around it's surface given its porosity. I think
> I'm gonna try that option first to see how severe is the vacuum loss when
> the cuts are made.
>
> Second option would be what Todd suggests, wich is a little trickier
> mostly because my surface needs to be 3000 mm x 2000 mm, so that's a lot of
> springs...
>
> I'll keep you informed as the project progresses.
>
> Thanks as always for your help :)
>
> El lun, 7 jun 2021 a las 17:11, Todd Zuercher ()
> escribió:
>
> > It might work, but you may have trouble with the pellet sticking in
> > the seat and not opening when you need it to, or worse yet if your
> > part doen't quite seal good enough to the table, sucking shut and
> > losing all holding power.
> >
> > What I've seen more commonly used is a spring loaded valve where a
> > spring pushes the pellet(ball) up to seal the vacuum port.  When no
> > part is in place the spring pushes the ball up to seal the vacuum
> > port, and the ball sticks up a bit above the part sealing surface.
> > When the part is placed on top, it pushes the ball down opening the
> > valve and allowing the vacuum to flow.
> >
> > Todd Zuercher
> > P. Graham Dunn Inc.
> > 630 Henry Street
> > Dalton, Ohio 44618
> > Phone:  (330)828-2105ext. 2031
> >
> > -Original Message-
> > From: Leonardo Marsaglia 
> > Sent: Saturday, June 05, 2021 11:50 PM
> > To: Enhanced Machine Controller (EMC)
> > 
> > Subject: Re: [Emc-users] OT: About a chat here on vacuum table ideas
> >
> > [EXTERNAL EMAIL] Be sure links are safe.
> >
> > I meant to say:
> >
> > When there is a part over that hole and before the pump is on, the
> > pellet will be resting on the groove. As soon as the pump is on the
> > vacuum will be immediately sealed by the part, not allowing the
> > suction to suck the pellet
> >
> > El dom, 6 jun 2021 a las 0:48, Leonardo Marsaglia
> > ( > >)
> > escribió:
> >
> > > Hello guys,
> > >
> > > I hope you're all doing well.
> > >
> > > Not so long ago (or may be yes) I recall reading someone on this
> > > list talking about an idea of using plastic pellets as closing
> > > valves for an MDF vacuum table.
> > >
> > > The basic idea was: The pellet falls into a spherical hole that has
> > > a round groove with a slight angle on its side. So when the vacuum
> > > is not applied the plastic pellet can slide thru the groove and
> > > leave the hole open (I imagine that the vacuum pump could be
> > > reversed so one can blow to clear the holes and force the pellets to
> the groove quicker).
> > > When there is a part over that hole and before the pump is on, the
> > > vacuum will be immediately sealed by the part, not allowing the
> > > suction to suck the pellet. Once the hole is again free, the suction
> > > will slide the pellet until the hole is sealed (useful to avoid
> > > vacuum loses on the path where the tool cuts the material).
> > >
> > > Are there any practical examples or any real life experience of this
> > idea?
> > > That would be more than useful.
> > >
> > > Thanks as always!
> > >
> >
> > ___
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>
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> 

[Emc-users] OT: Fanuc wrist

[Roland Jollivet]

Interesting, never thought they'd use a gear with so little engagement;

https://www.youtube.com/watch?v=iblqrfu5wdw
(note, it's immersed in oil)

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[Emc-users] homing off glass scale

[Roland Jollivet]

On Sun, 23 May 2021 at 03:31, Jon Elson  wrote:

> On 05/22/2021 07:12 PM, dave engvall wrote:
> >
> >> Has anyone tried homing off the reference channel on a
> >> glass scale? There is information on the web indicating
> >> that at least some of the chinese glass
> >> scales mask and compare the 4 lines each side of the
> >> reference mark in addition to the reference. This might
> >> imply that the usual homing routine would work.
> >> I haven't tried this only because I have nothing running
> >> at the moment capable of doing this.
> If the "reference channel" produces one pulse at a specific
> spot on the scale with no other pulses within a few tenths
> of an inch, you should be able to use it for precise
> homing.  You'd have a limit switch that would begin the
> search for index sequence of the homing routine.  Then, it
> would advance until it saw the pulse from the scale.  Just
> like the Z mark on a rotary encoder.
>
> Jon
>
>

I often feel like that I live in a world where cars have three wheels, and
no-one wants to believe that 4 wheels are better..

So  I don't understand why the reference strip in an encoder isn't half
black, half clear, along the full length. Now;
- there is only a single transition that marks the reference point
- it's always obvious which way to go to find that transition;  0:go left
   1:go right
- you don't have to worry (as much) about missing that obscure 'pulse'
- it will remove the homing dilemma plaguing machinists all over the world

What am I missing here?

Roland

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[Emc-users] Can't find the PP. Where is lspci or equiv ?

[Roland Jollivet]

Just enter the Bios on startup...


On Tue, 4 May 2021 at 21:05, Ed  wrote:

> Updating an old retrofit that uses step servos, Gecko 320's. I tried
> using lspci to find the ports (onboard and an addon ) and no such animal
> as lspci. Is there another good way to find the ports?
>
>
> Some year it is getting a Pico PWM i have setup on it but not today.
>
>
> Ed.
>
>
>
>
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[Emc-users] Worn Ball Screw?

[Roland Jollivet]

But I did find, when I went looking;

https://motorcityrepair.com/ball-screw-repair/



On Wed, 14 Apr 2021 at 18:17, Todd Zuercher  wrote:

> Thanks, No I did not.  But it appears they are in the UK, so not much help.
>
> Todd Zuercher
> P. Graham Dunn Inc.
> 630 Henry Street
> Dalton, Ohio 44618
> Phone:  (330)828-2105ext. 2031
>
> -Original Message-----
> From: Roland Jollivet 
> Sent: Tuesday, April 13, 2021 11:23 AM
> To: Enhanced Machine Controller (EMC) 
> Subject: [Emc-users] Worn Ball Screw?
>
> [EXTERNAL EMAIL] Be sure links are safe.
>
> Did you try PGM Reball (saw them on an old video I have)
>
>
> On Tue, 13 Apr 2021 at 14:38, Todd Zuercher  wrote:
>
> > Yes, near the limit switch, outside of the normal travel area, I can
> > not measure any backlash.  That pretty much points the finger squarely
> > at wear on the screw as the main culprit.  I think I have figured out
> the "springy"
> > backlash uptake mystery.  It is simply the weight of the screw sagging
> > down and resting on the nut pushing the table to the center of the
> > ball grooves (remember the screw is more than 14ft long.)
> >
> > Anyone know of any good ball-screw refitters in the States?  I already
> > checked with one and they didn't want to touch it.
> >
> > Todd Zuercher
> > P. Graham Dunn Inc.
> > 630 Henry Street
> > Dalton, Ohio 44618
> > Phone:  (330)828-2105ext. 2031
> >
> > -Original Message-
> > From: Stuart Stevenson 
> > Sent: Monday, April 12, 2021 11:12 PM
> > To: Enhanced Machine Controller (EMC)
> > 
> > Subject: Re: [Emc-users] Worn Ball Screw?
> >
> > [EXTERNAL EMAIL] Be sure links are safe.
> >
> > Plus or minus .010 is an amazing amount. Also, you mentioned another
> > area on the screw you saw .001 lost motion. This leads to a screw
> problem.
> > I would do what Jon Elson says as this sounds strange but I would
> > expect to find screw wear. If it was nut wear the backlash in all
> > areas of the screw would be close to equal. Not knowing the drive
> > train maybe there is a gear train and one area of the gear train has
> > worn teeth and where you found almost no lost motion is where the gear
> train is the best.
> > Expect screw wear but hope for a gear train problem.
> > HTH
> > Stuart
> >
> > On Mon, Apr 12, 2021 at 5:15 PM Jon Elson 
> wrote:
> >
> > > On 04/12/2021 09:48 AM, Todd Zuercher wrote:
> > > > Those here who have had to deal with a worn out ball screw.
> > > I'd dig into the works and examine everything.  It does NOT sound
> > > like simple wear.
> > > The rotating nut likely runs in a pair of either angular-contact
> > > bearings or tapered roller bearings.  There will be a preloading
> > > arrangement to constrain the nut.  Also, the screw is usually fixed
> > > at both ends.  If the clamp has gotten loose at one or both ends, it
> > > could allow some flex of the mount under load.  Attach a dial test
> > > indicator to the slide and read against the end of the screw, and
> > > watch for movement when you apply load.
> > >
> > > Some old ballnuts were actually TWO completely separate nuts that
> > > were preloaded against each other with Belleville washers.  It is
> > > possible some of the Bellevilles have cracked.
> > > Also, they often used dowel pins to align the two nuts rotationally.
> > > If one of the dowels has cracked, that could cause this kind of issue.
> > >
> > > Jon
> > >
> > >
> > > ___
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> > > https://lists.sourceforge.net/lists/listinfo/emc-users
> > >
> >
> >
> > --
> > Addressee is the intended audience.
> > If you are not the addressee then my consent is not given for you to
> > read this email furthermore it is my wish you would close this without
> > saving or reading, and cease and desist from saving or opening my
> > private correspondence.
> > Thank you for honoring my wish.
> >
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> >
> >
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[Emc-users] Worn Ball Screw?

[Roland Jollivet]

Ha ha, oops, they're in the UK

On Tue, 13 Apr 2021 at 17:22, Roland Jollivet 
wrote:

>
> Did you try PGM Reball (saw them on an old video I have)
>
>
> On Tue, 13 Apr 2021 at 14:38, Todd Zuercher  wrote:
>
>> Yes, near the limit switch, outside of the normal travel area, I can not
>> measure any backlash.  That pretty much points the finger squarely at wear
>> on the screw as the main culprit.  I think I have figured out the "springy"
>> backlash uptake mystery.  It is simply the weight of the screw sagging down
>> and resting on the nut pushing the table to the center of the ball grooves
>> (remember the screw is more than 14ft long.)
>>
>> Anyone know of any good ball-screw refitters in the States?  I already
>> checked with one and they didn't want to touch it.
>>
>> Todd Zuercher
>> P. Graham Dunn Inc.
>> 630 Henry Street
>> Dalton, Ohio 44618
>> Phone:  (330)828-2105ext. 2031
>>
>> -Original Message-
>> From: Stuart Stevenson 
>> Sent: Monday, April 12, 2021 11:12 PM
>> To: Enhanced Machine Controller (EMC) 
>> Subject: Re: [Emc-users] Worn Ball Screw?
>>
>> [EXTERNAL EMAIL] Be sure links are safe.
>>
>> Plus or minus .010 is an amazing amount. Also, you mentioned another area
>> on the screw you saw .001 lost motion. This leads to a screw problem.
>> I would do what Jon Elson says as this sounds strange but I would expect
>> to find screw wear. If it was nut wear the backlash in all areas of the
>> screw would be close to equal. Not knowing the drive train maybe there is a
>> gear train and one area of the gear train has worn teeth and where you
>> found almost no lost motion is where the gear train is the best.
>> Expect screw wear but hope for a gear train problem.
>> HTH
>> Stuart
>>
>> On Mon, Apr 12, 2021 at 5:15 PM Jon Elson  wrote:
>>
>> > On 04/12/2021 09:48 AM, Todd Zuercher wrote:
>> > > Those here who have had to deal with a worn out ball screw.
>> > I'd dig into the works and examine everything.  It does NOT sound like
>> > simple wear.
>> > The rotating nut likely runs in a pair of either angular-contact
>> > bearings or tapered roller bearings.  There will be a preloading
>> > arrangement to constrain the nut.  Also, the screw is usually fixed at
>> > both ends.  If the clamp has gotten loose at one or both ends, it
>> > could allow some flex of the mount under load.  Attach a dial test
>> > indicator to the slide and read against the end of the screw, and
>> > watch for movement when you apply load.
>> >
>> > Some old ballnuts were actually TWO completely separate nuts that were
>> > preloaded against each other with Belleville washers.  It is possible
>> > some of the Bellevilles have cracked.
>> > Also, they often used dowel pins to align the two nuts rotationally.
>> > If one of the dowels has cracked, that could cause this kind of issue.
>> >
>> > Jon
>> >
>> >
>> > ___
>> > Emc-users mailing list
>> > Emc-users@lists.sourceforge.net
>> > https://lists.sourceforge.net/lists/listinfo/emc-users
>> >
>>
>>
>> --
>> Addressee is the intended audience.
>> If you are not the addressee then my consent is not given for you to read
>> this email furthermore it is my wish you would close this without saving or
>> reading, and cease and desist from saving or opening my private
>> correspondence.
>> Thank you for honoring my wish.
>>
>> ___
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>> Emc-users@lists.sourceforge.net
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>>
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[Emc-users] Worn Ball Screw?

[Roland Jollivet]

Did you try PGM Reball (saw them on an old video I have)


On Tue, 13 Apr 2021 at 14:38, Todd Zuercher  wrote:

> Yes, near the limit switch, outside of the normal travel area, I can not
> measure any backlash.  That pretty much points the finger squarely at wear
> on the screw as the main culprit.  I think I have figured out the "springy"
> backlash uptake mystery.  It is simply the weight of the screw sagging down
> and resting on the nut pushing the table to the center of the ball grooves
> (remember the screw is more than 14ft long.)
>
> Anyone know of any good ball-screw refitters in the States?  I already
> checked with one and they didn't want to touch it.
>
> Todd Zuercher
> P. Graham Dunn Inc.
> 630 Henry Street
> Dalton, Ohio 44618
> Phone:  (330)828-2105ext. 2031
>
> -Original Message-
> From: Stuart Stevenson 
> Sent: Monday, April 12, 2021 11:12 PM
> To: Enhanced Machine Controller (EMC) 
> Subject: Re: [Emc-users] Worn Ball Screw?
>
> [EXTERNAL EMAIL] Be sure links are safe.
>
> Plus or minus .010 is an amazing amount. Also, you mentioned another area
> on the screw you saw .001 lost motion. This leads to a screw problem.
> I would do what Jon Elson says as this sounds strange but I would expect
> to find screw wear. If it was nut wear the backlash in all areas of the
> screw would be close to equal. Not knowing the drive train maybe there is a
> gear train and one area of the gear train has worn teeth and where you
> found almost no lost motion is where the gear train is the best.
> Expect screw wear but hope for a gear train problem.
> HTH
> Stuart
>
> On Mon, Apr 12, 2021 at 5:15 PM Jon Elson  wrote:
>
> > On 04/12/2021 09:48 AM, Todd Zuercher wrote:
> > > Those here who have had to deal with a worn out ball screw.
> > I'd dig into the works and examine everything.  It does NOT sound like
> > simple wear.
> > The rotating nut likely runs in a pair of either angular-contact
> > bearings or tapered roller bearings.  There will be a preloading
> > arrangement to constrain the nut.  Also, the screw is usually fixed at
> > both ends.  If the clamp has gotten loose at one or both ends, it
> > could allow some flex of the mount under load.  Attach a dial test
> > indicator to the slide and read against the end of the screw, and
> > watch for movement when you apply load.
> >
> > Some old ballnuts were actually TWO completely separate nuts that were
> > preloaded against each other with Belleville washers.  It is possible
> > some of the Bellevilles have cracked.
> > Also, they often used dowel pins to align the two nuts rotationally.
> > If one of the dowels has cracked, that could cause this kind of issue.
> >
> > Jon
> >
> >
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>
>
> --
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[Emc-users] Spindle rps and index

[Roland Jollivet]

On Fri, 19 Mar 2021 at 11:58, andy pugh  wrote:

> On Fri, 19 Mar 2021 at 01:46, John Dammeyer 
> wrote:
>
> > I take it then that you can't actually move the spindle to the index
> position unless you have some sort of control beyond velocity?
> 


My machine has a BT30 and an ATC.
The Fanuc AC spindle motor has no encoder, but there is an inductive sensor
on the spindle aligned for the ATC.
When you perform an M19 it spins a few times then stops on the sensor. (lit)

I suspect it turns a few times and takes a 'snapshot' of the drive
waveform. It then simply applies that waveform to hold the spindle in the
correct position
On a M19, it holds the spindle quite firm if I try to rotate it by hand,
but have not tried to move it past the encoder. I suspect it will give an
error..

Roland







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[Emc-users] OT: pcb milling

[Roland Jollivet]

Has anyone tried this for holding down PCB's when milling?

https://www.materialsampleshop.com/products/micro-suction-tape

Roland

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[Emc-users] Tandem home switches on single axis

[Roland Jollivet]

Lucky the proxy is PNP

Wire the proxy in series with the switch

- the proxy will pull the line UP
- the proxy Only has power when the switch is closed
- so the home position is only valid if the switch is closed AND the proxy
is active AND the proxy is interrupted. Then the line will get pulled high

Obviously you need to arrange the switch and proxy so this is optimal, get
the switch to become active half-way during the dark phase of the proxy

Roland



On Mon, 1 Mar 2021 at 06:23, Feral Engineer 
wrote:

> Hello Hive mind,
>
> Question for the group. I have an emco pc turn 55. I've successfully gotten
> everything working 100% on LCNC with the exception of one thing, the x and
> z axis utilize a mechanical limit switch to latch home position, but then
> each axis has a pnp proximity sensor that triggers the actual home position
> on a 1 ppr encoder of sorts. I've just been using the mechanical switches,
> but I'd like to try and get the proximity sensors working during the home
> sequence.
>
> Any suggestions on where to start getting this to work?
>
> Thanks in advance
>
> Phil
> The Feral Engineer
>
> Check out my LinuxCNC tutorials, machine builds and other antics at
> www.youtube.com/c/theferalengineer
>
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[Emc-users] Sheet metal operations.

[Roland Jollivet]

To throw in my two cents;

I build a lot of prototypes, and get my parts laser cut, but a CNC turret
punch would be a great have.

I've toyed with the idea a lot and came up with this strategy;
- machine designed to up to 3mm sheet metal only, maybe half a full sheet
(1.2 x 1.2m)
- build a high speed nibbler rather than a turret punch
- the machine has two fixed tools, a 2x2 square punch, and a 2mm round punch
- high speed nibbling will allow almost any profile to be generated with
these two tools
- the machine would be a fixed gantry style, 2.4m wide, and the gantry beam
is simply loaded up with extra mass to prevent oscillations

The mechanism would be hydraulically driven, with the pumps on the floor,
and tubing up to the two cylinders
The 'pump' is an eccentric piston, and free runs all the time, pushing and
pulling oil into the tank. The volume is low
When a punch operation is required, a pin will shoot into the oil line,
redirecting the flow to one of the cylinders
The pin will stay in position if continuous nibbling is required, or can be
timed at intervals according to the sheet position
(yes, you don't want to side load the tool too much)

While the explanation is laborious, I think it's a simple setup to make..

Roland


On Tue, 2 Feb 2021 at 12:55, andy pugh  wrote:

> On Mon, 1 Feb 2021 at 21:49, John Dammeyer  wrote:
>
> > Anyway the plan was to at some time create an ELS controlled movable
> back fence for the 3:1 tool and an XY movement system for the Arbor press
> to give me limited punching capabilities like the attached picture.
>
> I have thought that this would be a good thing to have if I ever get
> round to making a CNC slotting head for my milling machine (Or if I
> find an OEM one for the mill at a reasonable price[1])
>
> Have you seen the Trumpf CNC punches? Fascinating machines:
> https://youtu.be/-xOR42xho9I
>
> I think that one limitation of such a device would be throat depth.
> The Trumpf machines have a huge one.
>
> There is probably value in mounting a linear rail to the bench in
> front of the arbor press and then mounting a couple of switchable
> magnets to the sliders just to manually move sheets in straight lines.
> (would probably work with think aluminium with a steel bar on top)
>
> Which reminds me of another fascinating sheet metal tool.
> https://youtu.be/OipSiPSRti8
> The inventor has, rather generously, written a web page on how to make
> your own.
> http://aaybee.com.au/Magnabend/Building%20Your%20Own%20Magnabend.html
> I have had a small amount of success improvising a similar arrangement
> with my mag-base drill.
>
> [1] Quite a fluid concept. The last time one came up it was £300 and
> far too expensive. If I saw one now at that price I would snap it up)
> --
> atp
> "A motorcycle is a bicycle with a pandemonium attachment and is
> designed for the especial use of mechanical geniuses, daredevils and
> lunatics."
> — George Fitch, Atlanta Constitution Newspaper, 1912
>
>
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[Emc-users] Small spring, very simple flat

[Roland Jollivet]

One way is to use Beryllium copper.
If you have a local PCB supplier, they will etch the parts from a .dxf
They normally keep stock since the material is used as battery springs.

Otherwise, a laser cutter who does saw blades might have material.

There's also steel binding strap used in crate packaging. Readily available
and quite springy.
I use it a lot to keep vice parallels in place.

Roland


On Mon, 25 Jan 2021 at 00:13, Nicklas SB Karlsson  wrote:

> Need a small springs, not very many, very simple flat metal. Force in
> middle should be around 150N and guess 45mm long, 10mm wide , 0.6mm
> thick will do the trick. Anybody have any idea where it is possible to
> buy suitable material?
>
> Have been looking on a used handsaw, probably rather good steel, it hit
> a nail anyway and would make many enough to try out it work well but do
> not have anything hand to heat it, to hard now and it to be hardened
> then cut.
>
>
> Nicklas Karlsson
>
>
>
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[Emc-users] I wonder if I can fix it?

[Roland Jollivet]

On Thu, 7 Jan 2021 at 01:35, Gregg Eshelman via Emc-users <
emc-users@lists.sourceforge.net> wrote:

> I wonder if a replacement cup spline with an elastomeric part would work?
> Make teeth that interlock at the side of the spline wall and the back
> plate, with a thin filler of high durometer flexible urethane, bonded to
> the metal with something like Smooth-On Ure-Bond II.
> 



One way to make the spline would be to sinter it. The steel powders are
readily available.
While the shape is readily attainable, I don't know how well sintered parts
stand up to long term flexing..

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[Emc-users] I wonder if I can fix it?

[Roland Jollivet]

On Wed, 6 Jan 2021 at 17:22, andy pugh  wrote:

> On Wed, 6 Jan 2021 at 14:52, Ralph Stirling
>  wrote:
> >
> > Along those lines, could curved "teeth" like cycloidal reducers be used
> with a flex element?
>
> Here's something I designed earlier :-)
>
> https://youtu.be/VrvwlPxRhKU
>
>
I did a similar thing a while back, wanting to see if I could make a single
stage gear-gear reducer. Of course, at speed it becomes a wobbulator,
unlike the flex coupling being balanced.

I had the parts laser cut to check the meshing and the resolution came out
quite well. I can send a pic of the actual gears when I get back to the
workshop..
Here is a pic of the gears and a universal coupling I would use to take off
power.
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[Emc-users] I wonder if I can fix it?

[Roland Jollivet]

I've been pondering this for a while now, wondering if there's a design
shape that has been missed.
In terms of a fresh design, things that could be done;
- increase the length of the cup
- put cutouts in strategic places
- use a cone rather than a cup
- make the cup in more than one piece (flexspline +CV bearing)



On Tue, 5 Jan 2021 at 19:28, andy pugh  wrote:

> I bought an FHA-17C actuator from eBay. It was cheaper than normal,
> for parts or not working.
> It clearly had the cables cut off, so I decided to gamble.
>
> It turns out that things were worse than I hoped.
>
> https://photos.app.goo.gl/p3SL2Bwv2b9yd5XJ9
>
> I am seriously considering trying to make a new flexspline. I mean,
> how hard can it be?
>
> --
> atp
> "A motorcycle is a bicycle with a pandemonium attachment and is
> designed for the especial use of mechanical geniuses, daredevils and
> lunatics."
> — George Fitch, Atlanta Constitution Newspaper, 1912
>
>
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[Emc-users] Gecko G213V failed yet again.

[Roland Jollivet]

Solder a bridging wire under the pcb directly to the output Fet or whatever.
And/or maybe solder wires from the posts to an off-board connector so there
are no connectors on the board itself.



On Tue, 8 Dec 2020 at 06:39, John Dammeyer  wrote:

> The attached photo is of the last time but this time it's not much
> different.  I've resoldered the posts, cleaned everything up including
> polishing the posts and installed a new connector.  With only a few minutes
> running the connector is already quite hot.
>
> So I'm guessing the problem is in one of the middle layers of the PC board
> and either the fibreglass is already so carboned up that it's conducting or
> the trace for the one winding is pretty well toast and has a high
> resistance therefore acting like a toaster.  8-(
>
> So it's a 1200 oz-in stepper motor with a 60V power supply moving the knee
> up and down using a 3:1 reduction to the 0.25" pitch screw.
>
> Any suggestions for an alternative drive?  Really don't want to get
> another Gecko at $201.65 Cdn.
>
> Since I still have two extra HP_UHU drives and 2 STMBLs going to a DC
> Servo motor wouldn't be any more expensive other than the work of mounting
> it and maybe increasing the reduction ratio.  So maybe I should just look
> for an AC or DC Servo motor.
>
> John
>
>
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[Emc-users] OT: probing query_01

[Roland Jollivet]

Hi All

I'm wondering about probing, maybe someone can shed light;

I want to make a touch probe, and looking at the classic Renishaw tripod
style, an obvious limitation is the lobing error.
Is this appreciable (<5um?) or is it dwarfed by taper-mounting and spindle
error?

So I'm wondering why M19 Pxx isn't used, to always turn the probe towards
the most sensitive direction?  Or is it? This could also negate any spindle
related error when touching off on opposite sides.

Alternatively, I could also make a very sensitive one-direction-probe and
always use M19 Pxx when touching off, much as one does with a lever dial
indicator.
(and have a separate Z probe)

Roland

PS, I don't have a M19-able spindle or probe yet, so I might be off in my
assessment..

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[Emc-users] Cutting fluid

[Roland Jollivet]

The smell of many coolants make me feel nauseous, and that stuff surely
gets to the liver if on your skin
Have a look at this stuff. I haven't used it myself but intend to.

https://www.mmsonline.com/products/clear-metalworking-fluid-engineered-for-easier-part-cleaning



On Wed, 21 Oct 2020 at 21:36, Nicklas SB Karlsson  wrote:

> I learned cutting fluid could be unhealthy. Anyone here have any
> experience?
>
> First thing I think about is ordinary cooking oil. It might not have the
> best performance but as it is more or less just a little bit of hobby
> machining unless to bad this is not very important, it is more important
> there is no health problems.
>
>
> Nicklas Karlsson
>
>
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[Emc-users] OT: Fanuc 0M setup

[Roland Jollivet]

Thanks for all the replies.
I'll know more when I get the machine. The agent will probably do the mod,
but even then I'm hesitant. If he screws up I'm the one sitting with a big
anchor...

I think I'll use it as-is for a few months, learn more, then take the leap.

Roland

On Tue, 20 Oct 2020 at 22:16, Dave Cole  wrote:

> I forget what version of the Fanuc Controllers this applies to, but
> there were some controllers that had a compact flash slot on the front.
> The compact flash slot was used to load and read out the PLC program
> logic and the other controller settings.   The programming was done
> offline on a laptop and the logic was written to the compact flash
> module, then the module was used to load the controllers memory.
> It was awkward.
> You needed a $$ license to run the software.
> This was years ago, but the Fanuc tech guy was charging way over $200/hr
> to make changes.
> Dave
>
> On 10/20/2020 10:49 AM, Jon Elson wrote:
> > On 10/20/2020 02:29 AM, Roland Jollivet wrote:
> >> Also, if I want to ditch the controller at a later stage, are the Fanuc
> >> servo drives interfaceable to EMC?
> >>
> > Can you say what servo amps you have?  The oldest Fanuc had standard
> > analog velocity servos, but instead of a DC tachometer, they
> > synthesized the tach signal from the encoder.  Some machines had the
> > tach in the motor but didn't use it, so it could be set up to use the
> > existing tach.  This applies to the brush motor (yellow cap) series.
> >
> > Later units had brushless motors (red cap) and the servo amps were
> > supplied 6 separate PWM signals, one for each transistor.  That uses
> > up a lot of PWM outputs.
> >
> > Jon
> >
> >
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[Emc-users] OT: Fanuc 0M setup

[Roland Jollivet]

Thanks Todd

Is there an easy way for me to check on the console if the ladder is
editable, as is?

Also, if I want to ditch the controller at a later stage, are the Fanuc
servo drives interfaceable to EMC?

Regards
Roland

On Mon, 19 Oct 2020 at 15:42, Todd Zuercher  wrote:

> If your Fanuc machine came with PLC editing installed and enabled, then
> doing that part will be relatively simple.  (All of the Fanuc machines I'm
> currently working with have).  But that doesn't mean that yours does.  We
> have Fanuc machines from 3 different manufactures all built around the same
> time period (2001-2006) and they all have different Ladder editing
> packages.  Some I have to look at and edit the ladder through the control's
> user interface, others require a separate ladder editing program (that did
> come installed on the machine.)  The trickier part might be finding unused
> IO points to physically connect to the control.  if there are unused io
> pins available, it might not be much more than adding wires to un used pins
> on plugs.  But it could get expensive if new io modules need to be added to
> the control.
>
> Todd Zuercher
> P. Graham Dunn Inc.
> 630 Henry Street
> Dalton, Ohio 44618
> Phone:  (330)828-2105ext. 2031
>
> -Original Message-
> From: Roland Jollivet 
> Sent: Monday, October 19, 2020 3:45 AM
> To: Enhanced Machine Controller (EMC) 
> Subject: [Emc-users] OT: Fanuc 0M setup
>
> [EXTERNAL EMAIL] Be sure links are safe.
>
> Hi All
>
> I'm looking at getting a small VMC that has a Fanuc 0M controller on it.
>
> Much to my chagrin, I found out that there is no I/O on the machine. (for
> fixtures, probes etc.)  I was expecting a Harting plug on the side.
> So any functionality has to be 'enabled' and hardware added and brought
> out to a plug.
>
> So the hardware side is easy enough, to add a few relays, but then this
> functionality still has to be enabled in the controllers ladder logic.
>
> So does anyone know if this is easy to do? Maybe just a password and do it
> from the user keypad?
> Or does one need special cables and codes for a secret society?
>
> Roland
>
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[Emc-users] OT: Fanuc 0M setup

[Roland Jollivet]

Hi All

I'm looking at getting a small VMC that has a Fanuc 0M controller on it.

Much to my chagrin, I found out that there is no I/O on the machine. (for
fixtures, probes etc.)  I was expecting a Harting plug on the side.
So any functionality has to be 'enabled' and hardware added and brought out
to a plug.

So the hardware side is easy enough, to add a few relays, but then this
functionality still has to be enabled in the controllers ladder logic.

So does anyone know if this is easy to do? Maybe just a password and do it
from the user keypad?
Or does one need special cables and codes for a secret society?

Roland

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[Emc-users] driver for a DC motor for a BS-1.

[Roland Jollivet]

Maybe this is good for you, if available locally;

https://www.olimex.com/Products/Robot-CNC-Parts/MotorDrivers/BB-VNH3SP30/open-source-hardware


On Wed, 14 Oct 2020 at 22:42, Gene Heskett  wrote:

> After it finally was delivered, testing looks good but now I need a
> controller, smaller and lower voltage than one of Jons pwm-servo's.
>
> This motor supposedly turns 220 rpms no load with 24 volts applied.
>
> It has an encoder on the rear which is making a 5.4khz quadrature signal
> when its running free, out of 4 wires, no index which is fine as I'll
> put a switch on the BS-1 for a home/index anyway.
>
> This motor draws 4 amps at max rated 100 watt input.
> No clue what the LRA amps is but it does jump pretty good getting started
> so I'd expect startup in-rush to be at least 10 amps.
>
> I'd like to control its position like a common rotary servo axis, so what
> do we have in our linuxcnc toolbox that looks like a bi-dir pwn
> controlled twin H bridge to run a 24volt brushed PMDC motor with a 10
> amp in-rush as if it were a servo?
>
> Thanks all.
>
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> If we desire respect for the law, we must first make the law respectable.
>  - Louis D. Brandeis
> Genes Web page 
>
>
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[Emc-users] Linux CAM.

[Roland Jollivet]

The problem with all the lower end CAM's is that they don't support Rest
machining, which makes them fairly useless if you're machining steel.
DeskProto didn't either as far as I remember. Now it does, but don't know
how good it is.

Roland



On Tue, 22 Sep 2020 at 13:59, andy pugh  wrote:

> Just spotted in a forum post:
>
> https://www.youtube.com/watch?v=vLcOeH1CTMQ
>
> DeskProto now has a Linux version.
> I have never used it, and I have no idea what the costs for the
> paid-for versions are.
> But it does appear to be a conventional application that won't
> suddenly stop working on the whim of the publisher (like Fusion)
>
> --
> atp
> "A motorcycle is a bicycle with a pandemonium attachment and is
> designed for the especial use of mechanical geniuses, daredevils and
> lunatics."
> — George Fitch, Atlanta Constitution Newspaper, 1912
>
>
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[Emc-users] OT: Synchronised motion using RS485/CAN bus motors

[Roland Jollivet]

Have you looked at the manual?

These drives are used on real machines...


On Wed, 19 Aug 2020 at 22:36, N  wrote:

> > Have a read on the manuals for the Yaskawa Legend 01  or 04
> >
> > It uses serial at 9600 !!! to command the drive.  (RS232 serial, or
> > ethernet interface)
> > The trick it uses is to send only new, relevant data, and not fixed
> packets
>
> Good enough for configuration but not coordinated movement in real time.
> Most drives have digital inputs for on/off, reverse/forward and analog
> input for speed. Guess you need an extra module/card to get a CAN interface.
>
>
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[Emc-users] OT: Synchronised motion using RS485/CAN bus motors

[Roland Jollivet]

Have a read on the manuals for the Yaskawa Legend 01  or 04

It uses serial at 9600 !!! to command the drive.  (RS232 serial, or
ethernet interface)
The trick it uses is to send only new, relevant data, and not fixed packets

Roland


On Wed, 19 Aug 2020 at 01:31, Frank Tkalcevic 
wrote:

> An off topic question, not directly LinuxCNC related...
>
> How are motors on a serial bus controlled and synchronised?
>
> My only real control experience is with LinuxCNC with Mesa and parallel
> port hardware where commands and feedback and precisely timed.  Sending
> commands and receiving feedback over a serial link I would expect to cause
> synchronising problems, and the bandwidth would reduce the update rate.
>
> How are these issues handled?  I tried googling this, but didn't find much
> -  I wasn't sure what to search for.
>
> Thanks,
> Frank
>
>
>
>
>
>
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[Emc-users] Quiet toothed belts.

[Roland Jollivet]

For that size I would use an HTD 5M. Maybe a 8M (8mm pitch)

A benefit too, us that most vehicles use this dimension for the cambelts,
so you can easily get belts. And even scrapped pulleys that are still
perfectly good. Pulleys are expensive and you can get a scrapped pulley for
< $1

Then there's GT2, an update on THD, but you can use GT2 belts on HTD
pulleys;
https://sdp-si.com/products/timing-belts/gt5.php



On Fri, 24 Jul 2020 at 21:04, John Dammeyer  wrote:

> What's the quietest profile/size belt for driving a spindle with 2HP up to
> 3000 RPM.
>
> I recall someone saying the round groove is the best for this.   Since
> we've been talking about gear cutters are there special cutters for that
> belt profile available?
>
> Thanks
> John
>
>
>
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[Emc-users] off topic: pwm with a stepper driver/motor

[Roland Jollivet]

I had a friend that had a motorised telescope.
It had a DC motor, with a very high reduction ratio. I think one would see
fluctuations with a stepper motor.

Also, I wouldn't use a belt at all. Drive a smooth roller and use a
friction drive against a large disc. This also allows you to manually turn
by slipping the disc on the roller for an easy setup. Most theodolites use
this arrangement. Teeth will just be too jerky when viewing stars..



On Fri, 10 Jul 2020 at 11:39, andy pugh  wrote:

> On Fri, 10 Jul 2020 at 02:00, Chris Albertson 
> wrote:
>
> > Belts can go to about 6:1 at best a double belt reduction only goes to
> 36:1
>
> I don't see why there is any limit to the possible reduction of a belt
> drive, if idlers are added to increase the wrap.
> If I was doing this (and this particular application is something that
> I have considered) I think that I would use a rotary variant of the
> "servobelt" system: Glue a length of T-section beliting to a circular
> component with the teeth pointing out to make a sprocket, and then
> have a close-spaced  pair of rollers to keep the belt wrapped round
> the sprocket except for a short loop that pops out and wraps round the
> stepper pulley.
>
>
> > He is doing only
> > about 10 Hz.
>
> In that case I think that a user-space loop in something like Python
> would be fine, just monitor the time using an accurate RTC (GPS
> module?) and have the loop say "have I made as many pulses as I should
> have for this time of day?" and either make a pulse on a GPIO pin, or
> not, accordingly.
>
> --
> atp
> "A motorcycle is a bicycle with a pandemonium attachment and is
> designed for the especial use of mechanical geniuses, daredevils and
> lunatics."
> — George Fitch, Atlanta Constitution Newspaper, 1912
>
>
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[Emc-users] ghesk...@shentel.net

[Roland Jollivet]

Hi Gene

I don't know if you got this on the list, so I'm sending it directly to you
too.

Here

is the link to the Pferd product page. At pg 35 is what you want

Regards
Roland



On Sat, 4 Jul 2020 at 19:02, Gene Heskett  wrote:

> Greetings all;
>
> Specifically, my inability to find a wheel in cbn similar to the $20
> dremel diamond disk, something with a 6mm or 6.35mm shank that would fit
> in the er20 chuck on the 6040 mill.
>
> I'd like to put a prop under the front of my A axis to establish heel
> clearance then rotate the chuck after touching it off straight up, to
> the side angles needed to do the v-belt pulley John D. was asking about.
> That or most any other shape an HSS lathe tool needs sharpened at.
> Attacking HSS with diamond is a waste of time and burns up the expen$ive
> diamond.
>
> I have a 4" cup cbn wheel, but the arbors are junk, so its contact isn't
> true. At 3k revs, thats hard on the wheel by the time you can hear
> contact.
>
> So where can I src a cbn wheel small enough to run at 10k+ revs in the
> 6040's spindle?  Nearly 2 hours of googling came up empty below 3".
>
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> If we desire respect for the law, we must first make the law respectable.
>  - Louis D. Brandeis
> Genes Web page 
>
>
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[Emc-users] More cbn headaches

[Roland Jollivet]

See here

;

Pferd will usually have what you need. There are 6mm shanks


On Sat, 4 Jul 2020 at 19:02, Gene Heskett  wrote:

> Greetings all;
>
> Specifically, my inability to find a wheel in cbn similar to the $20
> dremel diamond disk, something with a 6mm or 6.35mm shank that would fit
> in the er20 chuck on the 6040 mill.
>
> I'd like to put a prop under the front of my A axis to establish heel
> clearance then rotate the chuck after touching it off straight up, to
> the side angles needed to do the v-belt pulley John D. was asking about.
> That or most any other shape an HSS lathe tool needs sharpened at.
> Attacking HSS with diamond is a waste of time and burns up the expen$ive
> diamond.
>
> I have a 4" cup cbn wheel, but the arbors are junk, so its contact isn't
> true. At 3k revs, thats hard on the wheel by the time you can hear
> contact.
>
> So where can I src a cbn wheel small enough to run at 10k+ revs in the
> 6040's spindle?  Nearly 2 hours of googling came up empty below 3".
>
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> If we desire respect for the law, we must first make the law respectable.
>  - Louis D. Brandeis
> Genes Web page 
>
>
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[Emc-users] Maths (wow)

[Roland Jollivet]

 When I was working with a Fanuc robot, and if in a tight space, I would
often get a 'singularity' error. Two axes are too parallel to each other.
Then you have to fiddle with the program to get out of the paradox.

Thing is, in all of my life of picking up things, my arm has never frozen
from a singularity error..

Why, well, my theory is that the joints are prioritised, then there should
be no doubt as to which joint takes precedence.

Just my Saturday morning blurt..


On Sat, 27 Jun 2020 at 04:59, Chris Albertson 
wrote:

> Ron,
>
> Have you ever written software for things like planning a path for a robot
> so as to get to a goal in minimum time and avoid obstacles?  What you end
> up with is a ba-zillion simultaneous equation to see if lines intersect
> then if statements to see if the intersection point is within the segment
> of interest. THen you see that this is slow so you do approximations with
> bounding boxes first.  It is just a lot of work to check if
> polygons intersect.  And planning requires a search through this many
> times.
>
> The examples seem to show that this can be easy.
>
> But perhaps his library hides the loops and if-statements he says you no
> longer need?   In a similar way I can used the Boot  C++ geometry library
> to ask if two objects intersect or if one is contained in the other.  But I
> know these are simply hiding all the line crossing checks from me
>
> In the CNC world, tool path planning is not much different from robot or
> self-drive car navigation. Geometry REALLY does apply to CNC.
>
> It seems to me that this new projective geometry library is different from
> the Boost geometry library in that objects are represented differently and
> fundamentally different algorithms used (because of the change in
> representation.)
>
> Algorithms and hence computational speed depend so much on how objects are
> represented.  What I thought I saw was a change in representation allowing
> an orders of magnitude faster computation or maybe just 100X less code.
>
> So is it smoke and mirror or woth following?
>
>
>
>
> On Fri, Jun 26, 2020 at 7:02 PM R C  wrote:
>
> > that is funny,  I am a mathematician, and actually took several classes
> > involving
> >
> > projective geometry. What is shown is somewhat of "special case"
> > scenarios it seems.
> >
> >
> > I don't really see how projective geometry would apply to anything cnc,
> > or be helpful, or apply
> >
> > to anything "real world" for that matter. It's part of a field called
> > 'topology', which, at the
> >
> > time, was kinda a prestigious thing to do. (now I think of it as a
> > conspiracy theory to sell lots of advil).
> >
> >
> > Ron
> >
> >
> > On 6/26/20 7:24 PM, andy pugh wrote:
> > > I was watching this presentation, and it was all rather interesting,
> > > but not directly relatable to LinuxCNC.
> > > https://youtu.be/tX4H_ctggYo
> > >
> > > But then this happened:
> > > https://youtu.be/tX4H_ctggYo?t=4443
> > >
> >
> >
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> >
>
>
> --
>
> Chris Albertson
> Redondo Beach, California
>
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[Emc-users] dxf2gcode

[Roland Jollivet]

my 2 cents..
When saving the .dxf, try saving as a R14 format. This is easily read by
most programs. The newer versions are full of headers that may cause
problems. The files are in ASCII so you can examine what's there and
compare versions.

I watched the video. Interesting. It looks like a 'scratchpatch' is needed
where the blade can be taken to re-orient for the next cut, instead of
trying to do a 360 on the spot and mess up the work..

Roland


On Thu, 25 Jun 2020 at 22:13, Martin Dobbins  wrote:

> Just found a YouTube video about that, problem solved-maybe.  Thanks, Todd
>
> https://www.youtube.com/watch?v=40CRimcwAZo
>
> Martin
>
> 
> From: Todd Zuercher
>
> Freecad's g-code tools also includes drag-knife dress-ups.  I haven't
> tried to use them but think I'm about to.  (I have to set up some tool
> paths for a glass cutting head we just purchased (which is more or less a
> drag-knife.)
>
> Todd Zuercher
> P. Graham Dunn Inc.
> 630 Henry Street
> Dalton, Ohio 44618
> Phone:  (330)828-2105ext. 2031
>
> -Original Message-
> From: Martin Dobbins 
> Sent: Thursday, June 25, 2020 2:23 PM
> To: Enhanced Machine Controller (EMC) 
> Subject: Re: [Emc-users] dxf2gcode
>
> [EXTERNAL EMAIL] Be sure links are safe.
>
> I really like openscad, and the uphill struggle with Freecad has just
> begun to get easier.  I had no idea that Freecad could make g code until
> Todd just told me 
>
> The beginning of this video has a pretty good illustration of how a drag
> knife works (it's different):
>
> https://www.youtube.com/watch?v=8jHS2uZpfJg
>
> 
> From: Glenn Edwards
>
> All,
>
> I have purchased Q-Cad recently, the DXF portion is free and the CAM costs
> extra, and have found the DXF editor pretty good.  I have struggled with
> the CAM portion that does the DXF to G-code, however.  It does not seem
> well supported- email inquiries go unanswered.  My two-cents.
>
> Best regards,
> -- --
> Glenn
> Rapid Converting LLC
> gl...@rapidconverting.com
> www.rapidgasket.com
>
>
> On Thu, Jun 25, 2020 at 10:47 AM Todd Zuercher 
> wrote:
>
> > Freecad can make G-code directly, leaving out the DXF middle man.
> > Have you tried that?
> >
> > Todd Zuercher
> > P. Graham Dunn Inc.
> > 630 Henry Street
> > Dalton, Ohio 44618
> > Phone:  (330)828-2105ext. 2031
> >
> > -Original Message-
> > From: Martin Dobbins 
> > Sent: Thursday, June 25, 2020 1:34 PM
> > To: Enhanced Machine Controller (EMC)
> > 
> > Subject: Re: [Emc-users] dxf2gcode
> >
> > [EXTERNAL EMAIL] Be sure links are safe.
> >
> > I've tried two coming from Freecad, both saved as "Autocad dxf",  one
> > was a simple 2D fully constrained 20mm square and the other was the
> > same thing padded to a thickness of 0.254 mm.  I can try a dxf from
> > another source if that is the problem.
> >
> > Martin
> >
> >
> >
> > 
> > From: Sebastian Kuzminsky
> >
> > On 6/25/20 10:43 AM, Martin Dobbins wrote:
> > > I'm trying to use this on Ubuntu 20.04 because I'm looking to write
> > > some
> > g code for a tiny (Roland) drag knife, I wanted to see how it handled
> > corners.
> > >
> > > Unfortunately, while the gui will load OK when I try to load a dxf
> > > I'm
> > getting a runtime error:
> > >
> > > File "/usr/lib/python3/dist-packages/dxf2gcode/core/shape.py", line
> > > 609,
> > in abs_iter
> > >  raise StopIteration()
> > > StopIteration
> > >
> > > The above exception was the direct cause of the following exception:
> > >
> > > Traceback (most recent call last):
> > >File "/usr/bin/dxf2gcode", line 727, in open
> > >  self.load()
> > >File "/usr/bin/dxf2gcode", line 874, in load
> > >  self.makeShapes()
> > >File "/usr/bin/dxf2gcode", line 922, in makeShapes
> > >  self.makeEntityShapes(self.entityRoot)
> > >File "/usr/bin/dxf2gcode", line 973, in makeEntityShapes
> > >  self.makeEntityShapes(newEntityContent, ent_geo.Layer_Nr)
> > >File "/usr/bin/dxf2gcode", line 996, in makeEntityShapes
> > >  tmp_shape.AnalyseAndOptimize()
> > >File "/usr/lib/python3/dist-packages/dxf2gcode/core/shape.py",
> > > line
> > 175, in AnalyseAndOptimize
> > >  self.setNearestStPoint(Point())
> > >File "/usr/lib/python3/dist-packages/dxf2gcode/core/shape.py",
> > > line
> > 190, in setNearestStPoint
> > >  min_geo_nr, _ = min(enumerate(self.geos.abs_iter()),
> > > RuntimeError: generator raised StopIteration
> > >
> > > Any ideas for a fix?  This was supposed to be a quick project.
> >
> > That looks like a bug in dxf2gcode.  Can you post the DXF file that
> > causes the problem?
> >
> >
> > --
> > Sebastian Kuzminsky
> >
> >
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[Emc-users] Universal spindle speed control for $7

[Roland Jollivet]

I was going to suggest this at the start of the thread, but I thought it
would be considered too Heath Robinson..


On Thu, 18 Jun 2020 at 20:40, Chris Albertson 
wrote:

> I'm making good progress on my 3D printed CNC conversion.  I found a way to
> 3D print a spindle controller that should work for most small milling
> machines and small lathes.   The cost is "almost nothing".   These
> machines' spindles are controlled by turning a potentiometer so my new
> system simply uses a cheap model airplane servo to turn the shaft of a
> potentiometer.  The computer is 100% isolated from any high voltage or
> noise.
>
> These small mills will never be able to do things like rigid tapping so all
> they need is a simple and approximate way to control the RPM.  This speed
> control can be run "open loop" if plus/minus 20% is good enough or used
> with a spindle encoder in a closed PID loop as long as the PID is
> tunned not to aggressively.
>
>
> For anyone who does not know about these hobby servos:
>
>- They are not full rotation motors.  They turn only through about 250
>degrees, This is a good match to the pot as pots also rotate about this
>range.
>- The angle of the servo shaft is controlled by a PWM signal.
>- They are "dirt cheap" starting at about $5 amazon.com/4-Pack-MG996R
><
> https://www.amazon.com/4-Pack-MG996R-Torque-Digital-Helicopter/dp/B07MFK266B/ref=sr_1_2?dchild=1=mg+servo=1592502600=8-2
> >
>- They accept a 5-volt control signal, so they have a built-in computer
>interface.
>- They are fast (enough) and can move from full-low to full-high on 0.6
>seconds
>- They really are actual "servos" and have an encoder, motor driver, and
>gears all inside.
>
>
> So when LinuxCNC outputs a low-value PWM spindle control, the servo moves
> the pot to the low position.  As the PWM signal value gets larger the pot
> is moved closer to the high-speed position.
>
> In the picture below is a cartoonish render.  The green frame is one-piece
> 3D printed,  The red pannel and tan coupler are also 3D printed.  The motor
> sells on Amazon, four units for $20 and the pot is about a buck each.  Four
> M4 button head screws everything together.
>
> Here is a link to the current version CAD files and a viewer.   I'll be
> updating the files after the first prototype is printed.
> https://a360.co/2N95AiL
> I may make a top cover to protect the pot and keep fingers off the high
> voltage.
>
>
>
> [image: Red Neck Spindle Control v6.jpg]
>
>
>
> --
>
> Chris Albertson
> Redondo Beach, California
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[Emc-users] Cheaper than normal FHA-25B

[Roland Jollivet]

I've been thinking about 4th axes;
While motorised reduction drives are readily available, the issue is
obviously backlash.

One way to make a zero backlash drive is to use two identical
gearbox/drives. Place them at opposite ends of the axis, and pit them
against each other by a few encoder counts.
So they will track and retain the zero-backlash.

Of course, the total power available is now less than one drive motor, but
it is an option to use almost any pair of reduction drives that can be got.
But there is also the cost of the second servo amp.


On Fri, 15 May 2020 at 14:11, andy pugh  wrote:

> The normally appear on eBay at up to 6x this price.
> https://www.ebay.co.uk/itm/233587431605
>
> The B versions have conventional incremental encoders and hall
> sensors, so are easy to integrate. Lots of torque, zero backlash and a
> very strong and fancy big crossed-roller bearing make them an
> almost-complete 4th or 5th axis just needing a bracket and a drive.
>
> I have no connection with the vendor, if you order one and receive
> dolls-house furniture instead don't blame me.
>
> --
> atp
> "A motorcycle is a bicycle with a pandemonium attachment and is
> designed for the especial use of mechanical geniuses, daredevils and
> lunatics."
> — George Fitch, Atlanta Constitution Newspaper, 1912
>
>
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[Emc-users] Hal file naming conventions

[Roland Jollivet]

Just add a comment at the top referencing a text file where you have it all
described?


On Thu, 14 May 2020 at 06:42, David Berndt  wrote:

> Wondering if anyone cares to share with me a useful naming convention for
> your signals? Do you also use the name parameters to name your components
> or do you just stick with and2.0 thru and2.x?
>
> My hal config works fine, but I worry about anyone that might have to
> look
> at it after me, or even if I have to look at it again after a year or two.
>
> Apologies if this has come up before, I did a bit of light googling and
> didn't find much on the topic.
>
> -Dave
>
>
>
>
>
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[Emc-users] Encoder reset on homing to index

[Roland Jollivet]

No-one has mentioned the mechanics of the system.. (or have they?)

What is the mechanical coupling like between the stepper and the linear
scale. Obviously it's most susceptible to backlash and belt stretch.
If the stepper is holding fast, how much linear deviation can you get if
you try move the carriage to and fro?  (stiffness)
Also, how many steps/linear increment?



On Sun, 26 Apr 2020 at 16:47, dave engvall  wrote:

> Not that I know much about this but: It is my understanding that the
> rotary because it has less quantatization error does a better job on
> control but unless your machine is very tight a poorer job on position.
> Early on I tried my machine with a 5 um linear glass scale. It was very
> difficult to tune. Later on tuning with a rotary encoder was a cinch by
> comparison. I've not tried both scales yet but that is where I'm headed.
> Conversation with Stu and the group that did the installation might shed
> some light. Does the information  coming off the sensors need to be
> reallocated. Just thinking(?) out loud.
>
> On my machine, a well worn BP size, using I has never given me better
> following error. I get by with P, FF1, FF2, zero or very small D and no I.
>
> just my tuppence!
>
> Dave
>
> On 4/25/20 10:56 PM, David Berndt wrote:
> > The rotary loop works fine by itself.
> >
> > The linear loop, as it's just an I term is pretty useless/non
> > functional by itself. Maybe you could argue it's ok for really small
> > values of I, but then the settling time when using both PID loops
> > combined is terrible. I was under the impression that was as
> > designed/expected based on the
> >
> http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Combining_Two_Feedback_Devices_On_One_Axis
> >
> > Side question. When doing touchoff/tool touchoff is commanded position
> > or actual position used?
> >
> >
> >
> > Maybe I'll look at a different PID strategy. Perhaps I could add the
> > pid.y2.error value from the linear encoder to the pid.Y.command then
> > the servo encoder will really have its thumb in the tuning pie. The
> > linear encoder won't have to run any actual gain, just spit out the
> > current error vs commanded.
> >
> > -Dave
> >
> >
> > On Sat, 25 Apr 2020 23:44:46 -0400, Peter C. Wallace 
> > wrote:
> >
> >> On Sat, 25 Apr 2020, David Berndt wrote:
> >>
> >>> Date: Sat, 25 Apr 2020 23:13:59 -0400
> >>> From: David Berndt 
> >>> To: Peter C. Wallace 
> >>> Cc: "Enhanced Machine Controller (EMC)"
> >>> 
> >>> Subject: Re: [Emc-users] Encoder reset on homing to index
> >>> Resent-Date: Sat, 25 Apr 2020 23:39:11 -0400
> >>> Resent-From: "David Berndt" 
> >>> Resent-To: "emc-users@lists.sourceforge.net"
> >>> 
> >>> Resent-cc: "Peter C. Wallace" 
> >>>  Trying this again for the second time, no more attachments, only a
> >>> google photos link. I really mean it this time.
> >>> https://photos.app.goo.gl/xMK4Ep69i1SpznC58
> >>>
> >>> Here are some halscope screenshots. Would saving the halscope data and
> >>> distributing that be better/prefered? Not sure what the policy is here.
> >>>
> >>>
> >>> This isn't really revealing much to me. All the index-enables fire,
> >>> commands go to zero, feedback goes to 0 and then the PID.y.output takes
> >>> off, PID.y2(linear).output eventually catches on and doesn't do
> >>> anything
> >>> to help, seems to add fuel to the fire instead of acting in an opposite
> >>> direction it should.
> >>>
> >>> Please see screenshots, any thoughts are appreciated.
> >>>
> >>> -Dave
> >>>
> >>
> >> The runaway almost suggests you have one PID loop with negative
> >> feedback and one with positive feedback. Have you tried each loop
> >> individually?
> >>
> >>>
> >>>
> >>> On Sat, 25 Apr 2020 14:44:54 -0400, Peter C. Wallace 
> >>> wrote:
> >>>
>  On Sat, 25 Apr 2020, David Berndt wrote:
> 
> > Date: Sat, 25 Apr 2020 14:21:45 -0400
> > From: David Berndt 
> > To: "Enhanced Machine Controller (EMC)"
> > ,
> >Peter C. Wallace 
> > Subject: Re: [Emc-users] Encoder reset on homing to index
> > Thanks for the feedback Peter.
> >  I took the time to re-order my hal file (it's a bit of a disaster
> > with all the other non motion going-ons in there).
> >  Here is the relevant start of m addf's
> >   addf hm2_5i25.0.read  servo-thread
> > addf motion-command-handler   servo-thread
> > addf motion-controllerservo-thread
> > addf pid.x.do-pid-calcs   servo-thread
> > addf pid.y.do-pid-calcs   servo-thread #rotary
> > addf pid.y2.do-pid-calcs  servo-thread #linear
> > addf pid.z.do-pid-calcs   servo-thread
> > addf pid.a.do-pid-calcs   servo-thread
> > addf pid.s.do-pid-calcs   servo-thread
> >  addf sum2.3   servo-thread #pid.y.output
> > +pid.y2.output -> 'y-output' -> hm2_5i25.0.7i77.0.1.analogout1
> >  addf hm2_5i25.0.write servo-thread
> >   I excluded all the stuff below which is are things like servo
> 

[Emc-users] Who knows about LASIMM ?

[Roland Jollivet]

On Fri, 27 Mar 2020 at 11:23, Valerio Bellizzomi  wrote:

> It is a phenomenal machine
>
> http://www.lasimm.eu/
>
>
> 





I don't get it...

All those fancy robots and all they can show is a bit of crappy welding?



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[Emc-users] PMSM, STMBL Drive

[Roland Jollivet]

On Sat, 21 Mar 2020 at 18:32, Nicklas Karlsson 
wrote:

> > *rene-dev  * commented on May 7, 2018
> > 
> >
> > IRAM256-1567A2 or IRAM256-1067A2 can be used as replacement, but they
> > only have 15 and 10A, but thats plenty for most servos.
> > they are still available at mouser.
> >
> > and I see they are near 26bucks at
> >
> > https://m.th.aliexpress.com/item/32839176520.html
> >
> > and later said
> >
> >
> >   *rene-dev  * commented on Jun 21,
> >   2018
> >   <
> https://github.com/rene-dev/stmbl/issues/91#issuecomment-399050388>
> >
> > All A2 models seem to be out of stock now. The A models can be bodged in:
>
> Decided discrete transistor was a good idea, have sometimes been in doubt
> but then looking on availability of components it feels like a really good
> choice. Have prototype boards but nothing I dare to sell yet.
>
>
> Regards Nicklas Karlsson
>
>
I looked at this the last time it was discussed and thought these might be
a good choice. And re-lay the board;

https://za.rs-online.com/web/p/motor-driver-ics/1339905/

https://za.rs-online.com/web/p/microcontrollers/7238978/

Roland

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[Emc-users] where can I find

[Roland Jollivet]

Hi Gene

Why don't you;
- take a 6mm or 1/4in or similar bright rod. Maybe 20mm long;
- mount in the lathe and use the 1mm drill to make a hole
- go to the milling mahine
- place a 6mm centre drill bit in a 6mm collet
- start a drill hole in some scrap
- remove the 6mm drill and insert the drilled rod
- place loctite on the rear of the drill shank and place in the rod hole
- drop the Z until the 1mm drill bit centres in the 6mm start hole that you
made, which should set it quite straight
- do similar with other small drill bits

Regards
Roland


On Wed, 26 Feb 2020 at 20:36, Gene Heskett  wrote:

> Greetings all;
>
> I seem to have lost the ability to hold a drill bit in the 40 thou size
> range with the loss of the micro hf mill  I have 1.5 mm and 1mm collets
> for the teeny ER on the 6040's spindle but that won't take a 43 thou in
> the 1mm, and the 1.5mm will but runs it crooked by 3x the diameter of
> the drill with 10mm of stickout. I suspect I have a crappy set of
> collets. The 1.5mm is an 8 petal design, but the 1mm is a 4 petal and
> too stiff to allow it to take a 43 thou drill.
>
> I'm trying to do pilot holes to thread for 0-80 screws so I can push one
> of these ATS-667's around for good quadrature.  This ER is a stretch it
> a bit to get a 1/4 probe shank in it.
>
> So I guess the question is: Where can I get a decent 1mm collet, or maybe
> a teeny drill chuck that might hold a drill that small true? And has a
> shank that fits a 7-6 marked collet?
>
> This 1mm collet at only 4 petals might as well be solid steel. The 1.5mm
> is squeezed so hard by the time it grips the drill that the ejector
> grove is too small for the nut, or too high on the face and I have to
> remove the nut, then use pliers on the collet to remove it. Sloppy build
> is as kind as I can be in describing it.
>
> I see Shars has one on page 138, but its 2.5" long with a 1/4 inch shank
> and at $9.95, useing dremel pattern collets, "runs true" is not in its
> vocabulary.
>
> Thanks for ideas guys.
>
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> If we desire respect for the law, we must first make the law respectable.
>  - Louis D. Brandeis
> Genes Web page 
>
>
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[Emc-users] OT - simple motor wiring

[Roland Jollivet]

You can see the yellow wire bound with the others in the first pic. I'm
sure it's a coil wire.
Usually the frame wire is bolted to the ... frame.

You should measure the resistance of the two coils. They're quite
different. I'm not sure what the rule of thumb is on which is the start
winding, but it's out there.

Roland



On Mon, 20 Jan 2020 at 22:02, Peter Blodow  wrote:

> But this motor comes from Japan and, not knowing anything else, might
> very well be designed for the European market.
> Peter
>
> Am 20.01.2020 um 19:31 schrieb Dr. Andreas O. Lindner:
> > Hello, green-yellow is protected ground only in central Europe. In US it
> is a bare wire !
> >
> > Just my 2 cents,
> > Andreas
> >
> >
> >
> >> Am 20.01.2020 um 18:48 schrieb Peter Blodow :
> >>
> >> Isn't there something written on the green-yellow wire? In any case:
> don't connect any power to this wire, its PROTECTIVE GROUND!
> >> Peter
> >>
> >> Am 20.01.2020 um 18:21 schrieb grumpy--- via Emc-users:
> >>> thanks men
> >>> got it
> >>> neutral to black and blue
> >>> one side of capacitor to red
> >>> other side of capacitor to yellow
> >>> connect line to red or yellow
> >>>
> >>>
> >>> ___
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> >>> https://lists.sourceforge.net/lists/listinfo/emc-users
> >>>
> >>
> >>
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>
>
>
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[Emc-users] Whereare you getting your wire from?

[Roland Jollivet]

On Tue, 29 Oct 2019 at 04:48, Dave Cole  wrote:

> Menards was selling some surprisingly nice low voltage control wiring
> with two conductors two years ago for a good price.   I bought a hundred
> feet of it or so to wire up some air valves on a machine and I was in a
> rush.
> It was real stranded copper and I believe it was 18 gauge.
> Two conductors in a jacket.
> Its been on the machine for 2 years now, no issues.
>
> Dave
>
>
Is this something difficult to get in your country?

I can walk into any electrical store and ask for 2-core cable, 5A. It's
available in round (like 3-core) or 'twin-flex'. (figure 8)
Black or white...

Otherwise there's Red/Black twin-flex for DC applications.

Roland

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[Emc-users] ADC - realtime for load cell

[Roland Jollivet]

What will be the total travel of this ballscrew?
Is it static or does it travel as well?


On Thu, 19 Sep 2019 at 01:39, Curtis Dutton  wrote:

> my experiment is to use a force measuring device to proportionally control
> torque output on a servo attached to a ball screw.
>
> as a thought experiment imagine a platform hoisted by said ball screw. as
> you added weight to the platform the motor torque would increase to offset
> the weight and keep it steady. or you could set the required force equal to
> X kgs and with less than X kgs on the platform it would travel up
> proportionally. the motor would increase torque to maintain the force
> value. if more force than X the platform would travel down proportionally.
> the motor would decrease torque to maintain the set force value.
>
> in effect not a position commanded but a force commanded linear actuator.
>
> is there some othere device that would be better for this type of force
> measurement? in the 0 to about 500kg range.
>
> On Wed, Sep 18, 2019, 11:51 AM Chris Albertson 
> wrote:
>
> > in any case, even with lower 16-bit precision, the most important part of
> > the design is the analog portion that sits between the load cell and the
> > A/D converter.
> >
> >
> >
> > On Wed, Sep 18, 2019 at 6:38 AM Curtis Dutton 
> wrote:
> >
> > > Chris thanks for the info.
> > >
> > > I'm not exactly certain at this point what precision I need. I'll be
> > > determining that experimentally later. I will keep in mind what you
> have
> > > said, I'll deal with it after I get my hardware running.
> > >
> > >
> > > On Tue, Sep 17, 2019 at 6:17 PM Chris Albertson <
> > albertson.ch...@gmail.com
> > > >
> > > wrote:
> > >
> > > > If you want better than 16-bits and 1KHz then you also are going to
> > need
> > > a
> > > > very good quality analog signal conditioning and instrumentation
> > > amplifier.
> > > >   The analog circuit between the A/D converts and the load cell
> really
> > > does
> > > > matter.   You have to reject common-mode or the low bits will
> just
> > be
> > > > filled with 60Hz noise.  And you can not simply use a "brick wall"
> > filter
> > > > or you will not get the desired bandwidth through.  (If you are
> needing
> > > to
> > > > sample at 1K then you must care about 500Hz bandwidth.
> > > >
> > > > This matters a LOT more than which A/D chip you use.
> > > >
> > > > 22 bits is better than one part per million. Do you really need that?
> > It
> > > > will be hard to isolate all of the electrical and mechanical noise
> > > > especially
> > > >
> > > > On Tue, Sep 17, 2019 at 2:26 PM Curtis Dutton 
> > > wrote:
> > > >
> > > > > I have a pet project I'm starting that will involve reading a load
> > cell
> > > > in
> > > > > as near as real time as possible and using that input for servo
> > > control.
> > > > >
> > > > > I plan on using mesa hardware to interface to the equipment. Does
> > > anyone
> > > > > know of a nice way to interface hotsmot2 to a load cell?
> > > > >
> > > > > I would like a fairly high resolution. 16 bit minimum, the higher
> the
> > > > > better up to 22 bit I suppose. As well as the ability to sample at
> > the
> > > > > servo thread rate of 1 Khz.
> > > > >
> > > > >
> > > > > Thanks,
> > > > >Curtis
> > > > >
> > > > > ___
> > > > > Emc-users mailing list
> > > > > Emc-users@lists.sourceforge.net
> > > > > https://lists.sourceforge.net/lists/listinfo/emc-users
> > > > >
> > > >
> > > >
> > > > --
> > > >
> > > > Chris Albertson
> > > > Redondo Beach, California
> > > >
> > > > ___
> > > > Emc-users mailing list
> > > > Emc-users@lists.sourceforge.net
> > > > https://lists.sourceforge.net/lists/listinfo/emc-users
> > > >
> > >
> > > ___
> > > Emc-users mailing list
> > > Emc-users@lists.sourceforge.net
> > > https://lists.sourceforge.net/lists/listinfo/emc-users
> > >
> >
> >
> > --
> >
> > Chris Albertson
> > Redondo Beach, California
> >
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>
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[Emc-users] OT: loctiting cutters

[Roland Jollivet]

Hi All

Was wondering what you guys think about loctiting cutters in place, as a
principle.

First, here is a typical 2.2kW spindle

. It has a max torque of 1.75N.m  (ISO20 taper)

Now what if I MADE a tool holder that looks.. like this
 shrink fit holder, but
instead of shrink-fitting say, a 6mm jobber drill, I just loctited the bit
in place. That's all.

Below is the property of the Red loctite. I can't see how any drill bit or
cutter would come loose given approx 20mm of engagement. (slip fit)
While it is unorthodox, it's quite in keeping with today's glued-together
world..
Does anyone see an obvious reason why it's not in practice?

Roland

PS, I don't ever want to remove it..

Type Typical color code   Torque to break free(3⁄8-16 size bolt)
Torque to continue turning   Temperature range
High strength
■ Red
230 in-lb (25 N⋅m) 225 in-lb (25
N⋅m)−54 to 149 °C

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[Emc-users] Touching off and Gxx Home positions.

[Roland Jollivet]

On Sun, 14 Jul 2019 at 22:42, John Dammeyer  wrote:

>
> > M30 (and M2(  explicitly sets back to G54.
> > http://linuxcnc.org/docs/2.7/html/gcode/m-code.html#mcode:m2-m30
>
> Thanks.
> >
> > Maybe use G54 if you are only going to use one?
>
> There's a long story as to why I wanted two. But too involved.  I think
> once I have the Z axis home switch installed for Machine Workspace Home I
> can investigate the others.
>
> John 
>


Another trick to set the X, if you are using the vise, and want to be
quicker than using a wiggler;

- mount an accurate 10mm rod/shaft in the tool holder  (you could even just
use the current cutter)
- descend the Z (spindle off)
- set the DRO to -5mm
- slide the piece in the jaws until it touches the 10mm shaft. Clamp .
done..

Roland

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[Emc-users] Work holding machining Techniques

[Roland Jollivet]

> G0 X10 Y100 (equivalent to positioning by DRO)
> jog down to kiss the material "Touch Off" Z (equivalent to zeroing the DRO)
>

It's often suggested to jog down to touch off. Maybe onto some paper or
whatever.
I think it's a bad idea because of the risk of chipping the flutes, and in
the last 0.3mm it's difficult to gauge where you are.

Jogging up is better, backlash notwithstanding.
Use an accurate rod or the shank of an endmill, say 10mm
Jog upwards while you gently try to roll the rod under the cutter
As you near the crest of the rod you can see when you need to reduce the
increment
And if you overshoot, it's easy enough to lower and do it again

Roland

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[Emc-users] Work holding machining Techniques

[Roland Jollivet]

How bit is the part?
If your stock is a solid bar, or you can use a bar (BMS?) then just clamp
the whole bar in the vise, with enough material to the side of the vise.
Mill the overhang, flip, mill.
Then cut it off and skim the cut face.



On Sun, 14 Jul 2019 at 04:25, John Dammeyer  wrote:

> The attached picture shows a small knee Z axis switch plate mount to bolt
> onto my mill and cut with LinuxCNC.  The slotted holes are to allow it to
> move the switch assembly closer or further away from the knee.  The two
> small holes will be threaded to hold the switch plate which can move up and
> down it's slots to adjust the actual knee home position.
>
> Drawing is done.  CAM is done.  G-Code generated. Home is the bottom left
> corner.  Ultimately I'll have a profiling operation that adds a radius to
> the corners.  And I have to mill the rabbet on the bottom.
>
> Work holding is the issue.  What's an ideal process?   Clamp a slightly
> oversize piece in the vise and have the CNC drill the holes and mill the
> two slots?  Then clamp it upside  down onto a piece of MDF using the two
> slots as the place for the hold down bolts?  Then run the profile and
> rabbet code?
>
> Or is it better to drill a couple of holes first in approximately the
> correct location of the slots and profile first.  Then flip it and in the
> vise do the rest of the milling?  No need to try and line it up twice.
>
> Or maybe drill two mounting holes, then bolt it to a rectangular piece and
> clamp that in the vise so it's above the jaws.  Then profile and do the
> holes at the same time?  Still needs to be flipped for the rabbet but then
> it could be referenced to the fixed jaw corner for Home Position.
>
> Suggestions?
> Thanks
> John
>
>
>
>
>
>
> > -Original Message-
> > From: Gene Heskett [mailto:ghesk...@shentel.net]
> > Sent: July-11-19 7:02 PM
> > To: emc-users@lists.sourceforge.net
> > Subject: Re: [Emc-users] .ini file questions
> >
> > On Thursday 11 July 2019 13:12:17 John Dammeyer wrote:
> >
> > > > The value "HOME_OFFSET=" is the number value given to the point
> > > > where the home switch changes during the home_latch move.
> > > > The value "HOME=" is the position the joint will move to (relative
> > > > to the "HOME_OFFSET=" point) at the feed rate specified by
> > > > "HOME_FINAL_VEL=".
> > > >
> > > > So If you're using your negative limit switch as the home switch,
> > > > and specify HOME_OFFSET=-1 and HOME=0 after probing the switch the
> > > > axis will move to 1" (or 1mm) away from the switch with that point
> > > > given the value of 0 in the g53 machine coordinates.  If you were to
> > > > set HOME_OFFSET=0 and HOME=1, the point the machine would stop
> > would
> > > > still be the same but that position would now be given the value of
> > > > 1 in the machine coordinates.
> > > >
> > > > Todd Zuercher
> > >
> > > Thanks.  I tried all that and now it's perfect for me.  It allows the
> > > fairly significant X axis backlash to be taken out without re-tripping
> > > the home/limit switch which was a bit of an issue. To get around it I
> > > reduced the backlash setting which caused its own set of problems.
> > > All good now.
> > >
> > > Now for the EDITOR setting.   I can load a G-Code file, select the
> > > menu entry to edit a file.  If it's the LCNC one loaded at start-up
> > > I'm told it's read only.  If it's one of mine, nothing happens.  No
> > > editor. Nothing.
> > >
> > > I've been using Mousepad outside of LCNC but setting Editor to
> > > Mousepad doesn�t work nor does setting it to the desktop link
> > > /usr/share/applications.   Unlike Windows, unfortunately the link
> > > doesn't actually specify where the executable is.
> > >
> > > So what can I do.  How do I specify the editor so that it runs with
> > > the currently loaded G-Code file?
> > >
> > > From the doc:
> > > EDITOR = gedit - The editor to use when selecting File > Edit to edit
> > > the G code from the AXIS menu. This must be configured for this menu
> > > item to work. Another valid entry is gnome-terminal -e vim.
> > >
> > First off, that gedit is an accidental code scrambler, evict it from the
> > facility. Give your machine a net cable, Then use synaptic to survey
> > what might be handy to go with geany.  It has a plethora of pluggins.
> >
> > And then edit that .ini file to say geany.  It has not made a mistake
> > that wasn't my own clumsy fat & ancient fingers in 4 or so years and its
> > never scrambled a big 800 loc .hal file yet.
> > >
> > >
> > >
> > >
> > >
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> > >  
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> > >  
> https://lists.sourceforge.net/lists/listinfo/emc-users
> >
> >
> > Cheers, Gene Heskett
> > --
> > "There are four boxes to be used in defense of liberty:
> >  soap, ballot, jury, and ammo. Please use in that order."
> > -Ed 

[Emc-users] First project with LinuxCNC.

[Roland Jollivet]

The thing about home/limit switches is that you can actually mount them far
from the engagement point, say two feet away. Use a hard, sprung rod to
transfer the action.
I've also come across switches that you can barely depress with your
finger, so that any oil/gunk gets squeezed out the way before it trips.


On Thu, 11 Jul 2019 at 16:17, Gene Heskett  wrote:

> On Thursday 11 July 2019 00:11:33 John Dammeyer wrote:
>
> > Well.  Not the best in the world. And lots of false starts as much due
> > to CAM management and G-Code generation.  But the limit switch holders
> > for the Y axis are done.  LinuxCNCwith one parallel port, two HP_UHU
> > Servo drives, one Gecko Knee Stepper drive.   The HB04 Pendant made
> > this a lot easier.
> >
> > Now to figure out how to mount a Knee Home Switch.
> >
> > And properly configure a tool table with the tool heights.
> >
> > John Dammeyer
>
> Those look pretty darned solid John, better than any I've done, but I am
> usually more space constained too. My new 6040 gantry's y home is a jury
> rig if there ever was one, and subject to whatever overtravel up to
> about 1/16" before the gantry crashes.  So I have the switch, a teeny
> pushbutton mounted with about 10 thou of button travel, mounted on a
> 1/16" thick 2.5" length of alu about 3/8" wide, bolted to the front face
> of the bed so the switch hangs out past the bed facing to the rear, with
> a 4-40 screw planted in the face of the gantry edge to push it. The
> boltdown screws are a long inch away from the switch, allowing the alu
> to flex about 1/8" without permanent deformation after the switch is
> bottomed. With the 4-40 screw set for the length of stickout to keep it
> from crashing, I can feel the mount flex as it homes, but cannot see it.
> I've std roller micros in other places. With 5 dollars a bag of ten
> switches, repeatability is well under a thou all around. I'm pleased,
> which is what counts. Limits are set in the .ini file, about 50 thou
> from crashing at the other end of the range.
>
> I may replace the z motor yet, all of them are very small nema 23's, and
> with the weight of the spindle motor on the z sled, lift speed is
> restricted to about 1/3 the maxvel of the x and y dirs, currently set at
> about 190"/minute.
>
> No labels on the motors, and no data on the dip switch settings of the
> tb6560 drivers I took out, so motor currents are set in the low 2's
> based on motor heating. I replaced that whole control box since I was
> unable to even get a full translation of the Chinese manual out of
> googles translator. So it now has a quad of 2m542's that used to drive
> my hf mill. and a clone 1.5 horse 120 volt vfd.  Runs either direction.
> But if I use tool contact to set tlo with a g38.2, I have to clip a
> ground onto the tool. Too much of that grey epoxy paint to get a ground
> anyplace. Even the motor to spindle doesn't reliably get thru the
> spindles bearings.
>
> Thanks John.
>
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> If we desire respect for the law, we must first make the law respectable.
>  - Louis D. Brandeis
> Genes Web page 
>
>
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[Emc-users] OT: machine style

[Roland Jollivet]

I thought this is a nice clean axes configuration, for a lighter duty
machine
But one would have to be careful of to-fro rocking in the linear guides

https://www.datron.com/cnc-machine-products/inline.php

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[Emc-users] 8255 type cards

[Roland Jollivet]

Hi  all

This might expose my ignorance ;-) and I'm not wanting anyone to do
in-depth calculations for me..

In the days of ISA cards, the 8255 was quite popular, but now we're onto
PCI and PCIe

So, if one looks at the Mesa 5i25, it can read encoders because presumably
because the FPGA is doing the counting.

Now, if I used one pci-bridge 8255 type card and used all the I/O (A,B,C)
to support 3 encoders, could I use, say a Pic processor to read the encoder
and convert to 8bit data, and then;
These 8bits are presented to the 8255 ports so Lcnc can do a snapshot read
of the encoder values to close a servo loop.

With 8bit counters on the encoders, would Lcnc read the encoders fast
enough to run a servo based machine comparable to an open loop stepper
system? Obviously it has to read before roll-over or all is lost

So, lets say the encoder provides 5um linear resolution on an axis, moving
at 10m/min   (32ft/min or 0.05Furlong/min  ;-)
= 10 000 000um/5um /min
= 2 000 000 counts/min
= 33 333Hz counter rate

With a  /256 pic counter, roll-over will be at 130Hz or every 7.7ms
Could Lcnc cope with that?

Roland

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[Emc-users] OT; Induction servo motor

[Roland Jollivet]

I think I know how it can be done too. Will take a bit of work though..
But such a circuit/software would be very useful for rigid tapping on a
regular milling machine with a normal 3-phase induction motor.

Roland




On Sun, 30 Jun 2019 at 14:19, Nicklas Karlsson 
wrote:

> On Sun, 30 Jun 2019 12:18:24 +0200
> Roland Jollivet  wrote:
>
> > A while back there was some discussion on using an induction motor as a
> > servo motor. I can't find the thread..
>
> I think I know how this should be done but had to fight it for a while.
> Now it seems performance is very good, maybe similar to a permanent magnet
> motor but I did not compare though good performance on higher rpm I am
> still a little bit uncertain about. I used a slightly different algorithm I
> did not find in books/articles that seems to work really well.
>
> Some drives have vector control of induction motor but do not know
> performance of these.
>
> > Yesterday, at the scrapyard I hauled two of these exact motors off a
> roller
> > press;
> >
> http://www.lithronix.com/komori/komorimatic-water-fountain-roller-actus-power-motor-rebuilt-ni20-200fg-x4kt
> >
> > I was quite disappointed to find out there was no permanent magnets in
> > them, and there were no matching drives.
> > So they are induction, but perhaps made differently to your general
> > induction motor.
> > It's a beast of a motor for 200W...At least they come with a 1000 P/R
> > encoder
>
> 1000 P/R is most probably good enough.
>
>
> Nicklas Karlsson
>
>
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[Emc-users] OT; Induction servo motor

[Roland Jollivet]

A while back there was some discussion on using an induction motor as a
servo motor. I can't find the thread..

Yesterday, at the scrapyard I hauled two of these exact motors off a roller
press;
http://www.lithronix.com/komori/komorimatic-water-fountain-roller-actus-power-motor-rebuilt-ni20-200fg-x4kt

I was quite disappointed to find out there was no permanent magnets in
them, and there were no matching drives.
So they are induction, but perhaps made differently to your general
induction motor.
It's a beast of a motor for 200W...At least they come with a 1000 P/R
encoder

Roland

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[Emc-users] OT: laser rust removal

[Roland Jollivet]

I thought this is quite fascinating. (Sorry to all those who think it's old
hat..)

https://www.youtube.com/watch?v=ACGSzBXKONo

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[Emc-users] How come....

[Roland Jollivet]

Because no-one has posted anything?

On Thu, 9 May 2019 at 10:17, Peter Blodow  wrote:

>  there has been no incoming mail since May 6th?
> Peter
>
>
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