Re: [Emc-users] Feeds and speeds

[John Dammeyer]

Oops.  I fibbed but then it was 2 years ago. 
http://www.autoartisans.com/mill/XAxisBearingClamp.jpg
Rotary table used for the cap. 

But the lathe and ELS for boring to depth was used for the bearing hole.
http://www.autoartisans.com/mill/XaxisBoringClearanceHole.jpg

The Y axis was done on the mill.
http://www.autoartisans.com/mill/YAxisMachining-6.jpg

John


> -Original Message-
> From: John Dammeyer [mailto:jo...@autoartisans.com]
> Sent: February-19-20 6:30 PM
> To: 'Enhanced Machine Controller (EMC)'
> Subject: Re: [Emc-users] Feeds and speeds
> 
> 
> > From: Jon Elson [mailto:el...@pico-systems.com]
> > On 02/19/2020 12:02 PM, John Dammeyer wrote:
> > >
> > > And soft castings from scrap aluminium like extruded old window frames
> is
> > a challenge unto itself.  I too use WD-40 for that.  Been thinking of just
> using a
> > spray bottle with kerosene.  Supposed to be just as good and much
> cheaper.
> > >
> > Ugh, some extrusions are anodized, so a very mushy pure
> > aluminum (1100) core with a really HARD outer skin.
> > That is extremely hard even on carbide cutters, and will eat
> > plain HSS in seconds.  Even re-cast, it may contain
> > some of the aluminum oxide from the anodizing mixed into it.
> >
> > Jon
> 
> I must be doing something right.  These came out really nice.  A variety of
> scrap stock.
> http://www.autoartisans.com/mill/XAxis-AlmostDone1.jpg
> Flycutter wth carbide lathe tool for the surfacing.  Clamped onto faceplate
> and bearing hole bored on lathe for the X axis.  Boring head used on Y axis
> casting behind.  The X axis is a two part casting because I wanted to be able
> to turn it on the lathe.  The bearing clamps are bar stock.  The bearing clamp
> holes and counter bores were all accomplished with the DRO using XY
> dimensions from the drawings.
> John Dammeyer
> 
> 
> 
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Re: [Emc-users] Feeds and speeds

[John Dammeyer]

> From: Jon Elson [mailto:el...@pico-systems.com]
> On 02/19/2020 12:02 PM, John Dammeyer wrote:
> >
> > And soft castings from scrap aluminium like extruded old window frames is
> a challenge unto itself.  I too use WD-40 for that.  Been thinking of just 
> using a
> spray bottle with kerosene.  Supposed to be just as good and much cheaper.
> >
> Ugh, some extrusions are anodized, so a very mushy pure
> aluminum (1100) core with a really HARD outer skin.
> That is extremely hard even on carbide cutters, and will eat
> plain HSS in seconds.  Even re-cast, it may contain
> some of the aluminum oxide from the anodizing mixed into it.
> 
> Jon

I must be doing something right.  These came out really nice.  A variety of 
scrap stock.
http://www.autoartisans.com/mill/XAxis-AlmostDone1.jpg
Flycutter wth carbide lathe tool for the surfacing.  Clamped onto faceplate and 
bearing hole bored on lathe for the X axis.  Boring head used on Y axis casting 
behind.  The X axis is a two part casting because I wanted to be able to turn 
it on the lathe.  The bearing clamps are bar stock.  The bearing clamp holes 
and counter bores were all accomplished with the DRO using XY dimensions from 
the drawings.
John Dammeyer



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Re: [Emc-users] Feeds and speeds

[Jon Elson]

On 02/19/2020 12:02 PM, John Dammeyer wrote:


And soft castings from scrap aluminium like extruded old window frames is a 
challenge unto itself.  I too use WD-40 for that.  Been thinking of just using 
a spray bottle with kerosene.  Supposed to be just as good and much cheaper.

Ugh, some extrusions are anodized, so a very mushy pure 
aluminum (1100) core with a really HARD outer skin.
That is extremely hard even on carbide cutters, and will eat 
plain HSS in seconds.  Even re-cast, it may contain

some of the aluminum oxide from the anodizing mixed into it.

Jon


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Re: [Emc-users] Feeds and speeds

[Marshland Engineering]

See here

https://www.lubefinder.com/castrol-ilocut-154.html

With my syringes, I use maybe 5 cc a day. 5cc x 200 days = 1 litre. 

A years supply is Pounds $14.50. That is cheaper than water based cutting
fluid and I don't have sump to clean out.  

Cheers Wallace. 



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Re: [Emc-users] Feeds and speeds

[John Dammeyer]

Hi all,
Just used threading oil with a brush.  It got warm enough with 1/2" HSS, 390 
RPM, 5.5ipm that a bit of smoke came off.   Something like this could use a 
chamfering pass around the edges.
 
Ignore the small hole along the opening.  Just grabbed a scrap of angle that I 
had in the junk box.
 
  
 
Really have to learn how to hold the work more firmly.  
John
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Re: [Emc-users] Feeds and speeds

[dave engvall]

seed oils are long chain fatty acids linked to a glycerin. Feed stock 
for varnish and other coatings.


Enough double bonds so there is lots of opportunity for cross-linking. 
With out dryers (catalysts) they just turn gummy.  Organic cobalt compds 
have been used for years as dryers for the arts, finishes for wood, etc.


Dave

On 2/19/20 11:59 AM, Gene Heskett wrote:

On Wednesday 19 February 2020 14:29:42 dave engvall wrote:


Lots of illocut products on web... which one do you recommend?

Indeed kerosene works well for threading Al and cutting. Probably less
flammable also but being lazy I didn't check the flashpoints.


The highest flashpoint stuff I've fed a mister is safflower oil, sold as
cooking oil in the grocery stores.. Worked great squaring up a huge
block of dead soft alu that I was making to space a bearing on down the
shaft about 1.5" to get away from a worn spot created by the eccentric
collar of a fafner bearing, but it made such a mess of the area to clean
up that I've never made that mistake again.

Dave

On 2/19/20 11:05 AM, Marshland Engineering wrote:

Ilocut is far superior to WD40. If I could send samples, I would
send some.



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Cheers, Gene Heskett


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Re: [Emc-users] Feeds and speeds

[Gene Heskett]

On Wednesday 19 February 2020 14:29:42 dave engvall wrote:

> Lots of illocut products on web... which one do you recommend?
>
> Indeed kerosene works well for threading Al and cutting. Probably less
> flammable also but being lazy I didn't check the flashpoints.
>
The highest flashpoint stuff I've fed a mister is safflower oil, sold as 
cooking oil in the grocery stores.. Worked great squaring up a huge 
block of dead soft alu that I was making to space a bearing on down the 
shaft about 1.5" to get away from a worn spot created by the eccentric 
collar of a fafner bearing, but it made such a mess of the area to clean 
up that I've never made that mistake again.
> Dave
>
> On 2/19/20 11:05 AM, Marshland Engineering wrote:
> > Ilocut is far superior to WD40. If I could send samples, I would
> > send some.
> >
> >
> >
> > ___
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>
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Cheers, Gene Heskett
-- 
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 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
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 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] Feeds and speeds

[dave engvall]

Lots of illocut products on web... which one do you recommend?

Indeed kerosene works well for threading Al and cutting. Probably less 
flammable also but being lazy I didn't check the flashpoints.


Dave

On 2/19/20 11:05 AM, Marshland Engineering wrote:

Ilocut is far superior to WD40. If I could send samples, I would send some.



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Re: [Emc-users] Feeds and speeds

[Marshland Engineering]

Ilocut is far superior to WD40. If I could send samples, I would send some. 



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Re: [Emc-users] Feeds and speeds

[John Dammeyer]

> -Original Message-
> From: Jon Elson [mailto:el...@pico-systems.com]
> With soft aluminum, the key is to take light cuts and keep
> the feedrate up.  The problem is that when the metal is
> warmed even a little, it gets MUCH softer.  So, you want to
> keep the cut moving along as fast as possible to not allow
> heat to build up in one spot.  Coolant can also help with
> this.  Thick pieces of aluminum can draw the heat away, so
> it is less of a problem.
> 
> 6061-T6 (or -T651) cuts great, 5052 or 1100 is much trickier
> in this regard.
> 
> Jon
And soft castings from scrap aluminium like extruded old window frames is a 
challenge unto itself.  I too use WD-40 for that.  Been thinking of just using 
a spray bottle with kerosene.  Supposed to be just as good and much cheaper.
John Dammeyer



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Re: [Emc-users] Feeds and speeds

[Jon Elson]

On 02/19/2020 10:21 AM, dave engvall wrote:
Indeed WD-40 seems to work well for Al. I have some Al 
that is plain touchy. Creates heat very quickly and then I 
get adhesion. 6061-T6 seems to be OK.


With soft aluminum, the key is to take light cuts and keep 
the feedrate up.  The problem is that when the metal is 
warmed even a little, it gets MUCH softer.  So, you want to 
keep the cut moving along as fast as possible to not allow 
heat to build up in one spot.  Coolant can also help with 
this.  Thick pieces of aluminum can draw the heat away, so 
it is less of a problem.


6061-T6 (or -T651) cuts great, 5052 or 1100 is much trickier 
in this regard.


Jon


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Re: [Emc-users] Open source CNC architecture

[N]

> ...
> >> I guess what I am suggesting is that it's time for LinuxCNC to be 
> >> broken apart and a standardized interface for Ethernet control be 
> >> developed.  Once that could talk to dumb FPGA devices like the 7i92H 
> >> or to full blown standalone CNC controllers that can act as simple 
> >> DRO/Power Feed or even simple G-Code like the 3D printers.  Or be 
> >> connected to the much more powerful LinuxCNC to add, in addition to 
> >> G-Code the fancy tool changing apparatus along with robotic cells that 
> >> load and unload the parts.
> > 
> > You are completely missing the point. You don't need to 'break apart' 
> > LinuxCNC. It is designed from the ground up to be modular.

Yes as is now there is NML between the parts.

> 'break apart' is architectural change just like it happened to so many 
> GNU-Linux services or programs. Robotics is one of the closest functions 
> to CNC. Some robots depend on RT kernel but do not have or need GUI on 
> top of it.

Have some robots and thought maybe Linuxcnc could be used for these. Then one 
of these small boards would be nice if running without a GUI but for 
programming connect via TCP/IP which in practice almost certainly will be 
Ethernet or maybe WiFi from an ordinary computer with a GUI I would guess is 
the choice.


Regards Nicklas Karlsson


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Re: [Emc-users] Open source CNC architecture

[N]

> > Go for it. If you design the board the LinuxCNC developers would be very
> > willing to help you integrate it with LinuxCNC. Of course you'll have to
> > be able to produce it at a price that makes it attractive to buyers.
> >
> 
> No.  do not produce yet another board.   You want to use an existing one.
> There are so many in the under $20 range and even under $5.

Tried to provide the best help I had time for to someone yesterday working with 
NML. You could start there, once it is split so that it works over the network 
it should possible to put on one of these readily available cards. Tried to 
split once and think old TK worked but not new axis. Agree, use an existing 
board.

You have looked at how the different parts in Linuxcnc communicate?


> Any STM32 based development board can connect to a Linux PC using USB, SPI
> I2C or whatever then the board will have a dozen or two or more pins.  It
> will also have some useful hardware for making pulses and such.

They are really good and might work as is. Also use a lot less space than an 
old PC/laptop and are most probably also cheaper though in a lot of cases space 
for a computer is not an issue.


Regards Nicklas Karlsson


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Re: [Emc-users] Open source CNC architecture --> printer driver postscript <-> g-code

[N]

> On Sat, 15 Feb 2020, 19:41 N,  wrote:
> 
> > Printers talk postscript while CNC machines talk g-code, well not always
> > but quite often.
> >
> 
> And just as some folk hand-write G-code, I know a chap who habitually
> creates graphics in raw postscript.

Metoo almost, sometimes use LaTeX for documents then they have measurement data 
so that I do not have to add this manually. For G-code I thought the CAM module 
in the CAD was the choice unless maybe if it is something simple.


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Re: [Emc-users] Open source CNC architecture --> printer driver postscript <-> g-code

[dave engvall]

postscript isn't a bad language for 2D. ... and yes years ago I did 
exactly that.


Dave

On 2/19/20 7:52 AM, andy pugh wrote:

On Sat, 15 Feb 2020, 19:41 N,  wrote:


Printers talk postscript while CNC machines talk g-code, well not always
but quite often.


And just as some folk hand-write G-code, I know a chap who habitually
creates graphics in raw postscript.

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Re: [Emc-users] Feeds and speeds

[dave engvall]

Indeed WD-40 seems to work well for Al. I have some Al that is plain 
touchy. Creates heat very quickly and then I get adhesion. 6061-T6 seems 
to be OK.


Dave

On 2/19/20 4:32 AM, Stuart Stevenson wrote:

For aluminum I like WD-40.

On Wed, Feb 19, 2020 at 3:41 AM Marshland Engineering <
marshl...@marshland.co.nz> wrote:


Been machining for a living for 18 years.  One off and small runs. Been
there,
flood coolant, mist spray and now unless I'm doing steel or heavy aly, I
have
reverted to a 5 cc syringe with a thin needle and I spot the material or
cutter as it runs with neat cutting oil. If I'm surfacing a plate or
machining
around a big block, I put a few drops of cutting fluid on it and then
smear it
with a 1.5 inch paint brush.

I think I have said this before, but, Castrol Ilocut 154 (think mine was
called 64 when I bought a 20 litre drum 25 years ago and still using it
daily)
is a neat cutting oil that is fantastic.

If I skim 2 bits of aly, one dry and one with oil, I can easily see the
difference. Drip oil with deep pockets and then remove the swarf with
compressed air. Running the mister all the time makes every thing sticky.

I never mill aly without fluid. Aly friction welds to easily.

Aliexpress, 20 syringes with needles for a couple of $$

I now have syringes next to the drill press, mill and lathe.

I still use flood with steel if I have to remove heat.

Flood if you have a fully closed in machine.

Still use HSS for plastics. Seems to cut the best.

Cheers Wallace.





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Re: [Emc-users] RPI4 is pretty close to a decent machine - now linear scales and servos

[dave engvall]

On 2/19/20 4:16 AM, Les Newell wrote:

On 18/02/2020 23:54, Marshland Engineering wrote:
Just a correction, I have setup a few stepper systems with LinuxCNC 
and step
and direction is no problem. The problems came in when using 2KW 
servo drives

and linear scales on the axis.


The subject of using linear scales for feedback pops up every so often 
on this list and always the recommendation is not to do it. I just 
checked back through the list history and you were also told this. 
It's not a LinuxCNC or competence issue. It's a hardware issue.


Feedback loops like a very stiff connection between the motor and the 
encoder. Even a tiny amount of backlash or spring has a major effect 
on loop stability. Have you ever tried driving a car with badly worn 
steering? It's hard to keep a straight line. Linear scales have have 
the same effect on the feedback loop. If you fit encoders directly on 
your motors most of your tuning issues will go away. If the machine is 
very stiff and has very little backlash you MAY get away with using 
velocity mode drives with your scales. Even then it's likely to be 
twitchy to set up. In fact this was also suggested to you at the time.


Using linear scales for secondary feedback in addition to encoders on 
the motors can in some cases improve accuracy but this is a pretty 
advanced configuration and off hand I don't know of anyone who has 
done it with LinuxCNC. It is done on some high end commercial machines.

http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Combining_Two_Feedback_Devices_On_One_Axis


I have purchased and tried a 80V 20A Servo Drive upgrade Geckodrive 
G320X

DG4S-08020 DCS810 from ebay and it worked well on a small motor.


See above. A motor with a directly connected encoder is easy to set 
up. If you tried the G320 on your linear scale setup you would have 
had exactly the same tuning issues.


I think having the servo tuning external to the PC is a good option. 
This makes the

LinuxCNC servo installation much easier.


I have used position mode drives (step/direction), velocity mode and 
torque mode with LCNC, Mach, Eding CNC, my own custom controller and 
others. I've tested Gecko, Mesa, Rutex, Granite Devices, Xylotex, 
Kinco, Bosch, Yaskawa and others in various configurations so I have a 
reasonable sample set. In my opinion the best control scheme overall 
is torque mode with LinuxCNC doing the feedback. Velocity mode comes 
second and position mode (step/dir) a long way behind.


The drives like Gecko, Rutex R9x series and Xylotex are very basic and 
you have no way of knowing what following errors you are getting until 
the drives trip. It's difficult to get a really good tune without 
knowing what the drive is doing.


Configuring digital drives such as Kinco, Yaskawa etc with a couple of 
buttons and a tiny LED display is frustrating to say the least. GD, 
the later Rutex drives Kinco, and many other digital drives have their 
own tuning software (mostly Windows only) but I haven't yet found one 
that is easier to use than LinuxCNC with Halscope. Some drives have 
auto tuning but I've not yet seen auto tuning that does a really good 
job.


My Hurco mill came with Yaskawa brushless servos in velocity mode. The 
velocity tuning in the drives was very touchy and I struggled to get a 
good balance between accuracy and oscillation. Some hunting is to be 
expected with velocity drives but this was too much for my liking. I 
then switched to torque mode and my problems went away. No hunting and 
much lower following error. My lathe is torque mode with Mesa 2KW 
drives. Again very smooth, no hunting and very low following error. 
They are not without their issues though (see below). My router uses 
Bosch analog velocity mode drives. Following error is adequate for a 
router but being velocity mode they do hunt a bit when the machine is 
stationary. I will say velocity mode is generally a little easier to 
tune than torque mode so if you aren't fanatical about pushing the 
limits of your machine and you can put up with the hunting it's not a 
bad way to go.


Here are some of my impressions of various drives:

Gecko G320. Step/dir DC brushed. Rather rudimentary feedback loop. 
Fixed following error limit. You need to take them apart and attach an 
oscilloscope to tune them properly. I suffered from issues with random 
tripping that I never fully solved. Physical pots to adjust which is 
nice. Would I buy again? No.


Mesa 7i29. Analog PWM DC brushed. Cheap and powerful. Generate lots of 
electrical noise so it's well worth adding some filtering. I had 
issues with noise pickup on the encoder inputs, to the point where I 
ended up using them for my handwheels and used a separate encoder 
board for the servos. The onboard dc-dc converter let the smoke out 
once but I managed to fix it by replacing a couple of small surface 
mount transistors. I've run my lathe on this drive for many years and 
the DC-DC converter circuit looks pretty well designed so I am 

Re: [Emc-users] Open source CNC architecture --> printer driver postscript <-> g-code

[andy pugh]

On Sat, 15 Feb 2020, 19:41 N,  wrote:

> Printers talk postscript while CNC machines talk g-code, well not always
> but quite often.
>

And just as some folk hand-write G-code, I know a chap who habitually
creates graphics in raw postscript.

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Re: [Emc-users] Feeds and speeds

[Stuart Stevenson]

For aluminum I like WD-40.

On Wed, Feb 19, 2020 at 3:41 AM Marshland Engineering <
marshl...@marshland.co.nz> wrote:

> Been machining for a living for 18 years.  One off and small runs. Been
> there,
> flood coolant, mist spray and now unless I'm doing steel or heavy aly, I
> have
> reverted to a 5 cc syringe with a thin needle and I spot the material or
> cutter as it runs with neat cutting oil. If I'm surfacing a plate or
> machining
> around a big block, I put a few drops of cutting fluid on it and then
> smear it
> with a 1.5 inch paint brush.
>
> I think I have said this before, but, Castrol Ilocut 154 (think mine was
> called 64 when I bought a 20 litre drum 25 years ago and still using it
> daily)
> is a neat cutting oil that is fantastic.
>
> If I skim 2 bits of aly, one dry and one with oil, I can easily see the
> difference. Drip oil with deep pockets and then remove the swarf with
> compressed air. Running the mister all the time makes every thing sticky.
>
> I never mill aly without fluid. Aly friction welds to easily.
>
> Aliexpress, 20 syringes with needles for a couple of $$
>
> I now have syringes next to the drill press, mill and lathe.
>
> I still use flood with steel if I have to remove heat.
>
> Flood if you have a fully closed in machine.
>
> Still use HSS for plastics. Seems to cut the best.
>
> Cheers Wallace.
>
>
>
>
>
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Re: [Emc-users] Open source CNC architecture

[Les Newell]

No.  do not produce yet another board.   You want to use an existing one.
There are so many in the under $20 range and even under $5.


John was talking about a controller with a dedicated keypad and LCD as 
well as the buffering components you need for a breakout board. 
Basically a souped up ELS that can optionally talk to LinuxCNC. Nothing 
currently on the market has that. If you are going to that amount of 
work, having the CPU on board make sense. If you just need a brain in a 
box then I agree with you. Go with one of the really common boards such 
as Arduino.


Les



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Re: [Emc-users] RPI4 is pretty close to a decent machine - now linear scales and servos

[Les Newell]

On 18/02/2020 23:54, Marshland Engineering wrote:

Just a correction, I have setup a few  stepper systems with LinuxCNC and step
and direction is no problem. The problems came in when using 2KW servo drives
and linear scales on the axis.


The subject of using linear scales for feedback pops up every so often 
on this list and always the recommendation is not to do it. I just 
checked back through the list history and you were also told this. It's 
not a LinuxCNC or competence issue. It's a hardware issue.


Feedback loops like a very stiff connection between the motor and the 
encoder. Even a tiny amount of backlash or spring has a major effect on 
loop stability. Have you ever tried driving a car with badly worn 
steering? It's hard to keep a straight line. Linear scales have have the 
same effect on the feedback loop. If you fit encoders directly on your 
motors most of your tuning issues will go away. If the machine is very 
stiff and has very little backlash you MAY get away with using velocity 
mode drives with your scales. Even then it's likely to be twitchy to set 
up. In fact this was also suggested to you at the time.


Using linear scales for secondary feedback in addition to encoders on 
the motors can in some cases improve accuracy but this is a pretty 
advanced configuration and off hand I don't know of anyone who has done 
it with LinuxCNC. It is done on some high end commercial machines.



I have purchased and tried a 80V 20A Servo Drive upgrade Geckodrive G320X
DG4S-08020 DCS810 from ebay and it worked well on a small motor.


See above. A motor with a directly connected encoder is easy to set up. 
If you tried the G320 on your linear scale setup you would have had 
exactly the same tuning issues.



I think having the servo tuning external to the PC is a good option. This makes 
the
LinuxCNC servo installation much easier.


I have used position mode drives (step/direction), velocity mode and 
torque mode with LCNC, Mach, Eding CNC, my own custom controller and 
others. I've tested Gecko, Mesa, Rutex, Granite Devices, Xylotex, Kinco, 
Bosch, Yaskawa and others in various configurations so I have a 
reasonable sample set. In my opinion the best control scheme overall is 
torque mode with LinuxCNC doing the feedback. Velocity mode comes second 
and position mode (step/dir) a long way behind.


The drives like Gecko, Rutex R9x series and Xylotex are very basic and 
you have no way of knowing what following errors you are getting until 
the drives trip. It's difficult to get a really good tune without 
knowing what the drive is doing.


Configuring digital drives such as Kinco, Yaskawa etc with a couple of 
buttons and a tiny LED display is frustrating to say the least. GD, the 
later Rutex drives Kinco, and many other digital drives have their own 
tuning software (mostly Windows only) but I haven't yet found one that 
is easier to use than LinuxCNC with Halscope. Some drives have auto 
tuning but I've not yet seen auto tuning that does a really good job.


My Hurco mill came with Yaskawa brushless servos in velocity mode. The 
velocity tuning in the drives was very touchy and I struggled to get a 
good balance between accuracy and oscillation. Some hunting is to be 
expected with velocity drives but this was too much for my liking. I 
then switched to torque mode and my problems went away. No hunting and 
much lower following error. My lathe is torque mode with Mesa 2KW 
drives. Again very smooth, no hunting and very low following error. They 
are not without their issues though (see below). My router uses Bosch 
analog velocity mode drives. Following error is adequate for a router 
but being velocity mode they do hunt a bit when the machine is 
stationary. I will say velocity mode is generally a little easier to 
tune than torque mode so if you aren't fanatical about pushing the 
limits of your machine and you can put up with the hunting it's not a 
bad way to go.


Here are some of my impressions of various drives:

Gecko G320. Step/dir DC brushed. Rather rudimentary feedback loop. Fixed 
following error limit. You need to take them apart and attach an 
oscilloscope to tune them properly. I suffered from issues with random 
tripping that I never fully solved. Physical pots to adjust which is 
nice. Would I buy again? No.


Mesa 7i29. Analog PWM DC brushed. Cheap and powerful. Generate lots of 
electrical noise so it's well worth adding some filtering. I had issues 
with noise pickup on the encoder inputs, to the point where I ended up 
using them for my handwheels and used a separate encoder board for the 
servos. The onboard dc-dc converter let the smoke out once but I managed 
to fix it by replacing a couple of small surface mount transistors. I've 
run my lathe on this drive for many years and the DC-DC converter 
circuit looks pretty well designed so I am chalking this one down to 
random bad luck. Excellent support from Mesa. They even sent me 
schematics. Would I buy again? The 

Re: [Emc-users] Open source CNC architecture

[Chris Albertson]

On Mon, Feb 17, 2020 at 4:51 AM Les Newell 
wrote:

>
> Go for it. If you design the board the LinuxCNC developers would be very
> willing to help you integrate it with LinuxCNC. Of course you'll have to
> be able to produce it at a price that makes it attractive to buyers.
>

No.  do not produce yet another board.   You want to use an existing one.
There are so many in the under $20 range and even under $5.

Any STM32 based development board can connect to a Linux PC using USB, SPI
I2C or whatever then the board will have a dozen or two or more pins.  It
will also have some useful hardware for making pulses and such.

Don't make a board "adopt" one.

Here is a compromise 1/2 way approach I made for controlling a LIDAR from a
Linux PC.The design "adopts" a $3 STM board (it is blue in the drawing)
and there is a green PCB I made to conectorize it so the wiring is neat.
   Making these green boards is easy.For a CNC you would put connectors
on for the motors, encoders, limit switchesand power supply and do all the
interconnect on the PCB avoiding the typical rat's nest.The PCB cost
more to ship then to manufacture.

So at most made one of these green boards with just small passive parts and
connectors on it.   It takes just hours and it low risk then you "plug-in"
a STM32 based development board that acts as the brain.
https://github.com/chrisalbertson/NeatoLidarInterfacePCB
-- 

Chris Albertson
Redondo Beach, California

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Re: [Emc-users] Feeds and speeds

[Marshland Engineering]

Been machining for a living for 18 years.  One off and small runs. Been there,
flood coolant, mist spray and now unless I'm doing steel or heavy aly, I have
reverted to a 5 cc syringe with a thin needle and I spot the material or
cutter as it runs with neat cutting oil. If I'm surfacing a plate or machining
around a big block, I put a few drops of cutting fluid on it and then smear it
with a 1.5 inch paint brush.  

I think I have said this before, but, Castrol Ilocut 154 (think mine was
called 64 when I bought a 20 litre drum 25 years ago and still using it daily)
is a neat cutting oil that is fantastic. 

If I skim 2 bits of aly, one dry and one with oil, I can easily see the
difference. Drip oil with deep pockets and then remove the swarf with
compressed air. Running the mister all the time makes every thing sticky. 

I never mill aly without fluid. Aly friction welds to easily. 

Aliexpress, 20 syringes with needles for a couple of $$

I now have syringes next to the drill press, mill and lathe. 

I still use flood with steel if I have to remove heat.

Flood if you have a fully closed in machine. 

Still use HSS for plastics. Seems to cut the best. 

Cheers Wallace. 

 



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Re: [Emc-users] Open source CNC architecture

[Robert Murphy]

On 19/2/20 5:47 pm, Rafael Skodlar wrote:

On 2020-02-17 04:49, Les Newell wrote:



  One issue jumps to mind that is different.  The tiny shop I have
doesn't have room for a Keyboard, Mouse and Display by the lathe.  I
currently have a nice work triangle set up for the lathe toolbench
and tool cabinet.  It would require a lot of work to change that at
a cost of space lost somewhere else.


Monitor on the wall behind the lathe? Support arm bolted to the wall
for the keyboard? If you wanted these things you'd make room. As you
don't want them you won't make the room. I'm not saying that's a bad
thing. We just have different requirements.



And that's really, from my perspective all I am talking about.   If
have to add an external intelligence of some sort to do faster
stepping or PWM then the sky's the limit on what is added because
that 3GHz 1GB PC isn't fast enough to do what can be done with a
small 32 bit ARM if the dedicated $250 CNC boxes from China are to
be believed.


Go for it. If you design the board the LinuxCNC developers would be
very willing to help you integrate it with LinuxCNC. Of course you'll
have to be able to produce it at a price that makes it attractive to
buyers.


This is not "start from scratch" situation! We don't live in a vacuum!
SBCs are popping up all over the place:
http://linuxgizmos.com/category/boards/

One sysadmin motto I learned long time ago: "Be a lazy sysadmin. Do
whatever it takes to simplify or minimize your tasks. Just don't tell
to your boss or you'll get even more work to do" ;-)



If you can do it for the right price and if it has the I/O capability
I need I'll buy one for my next machine. The display stuff is of no
interest to me but keypads are always handy. I use modbus for my
keypads at the moment.


First thing to look for is what others are doing using with embedded
systems. Most COTS manufacturers support their products for 5 or even
10 years. And there are alternative HW sources. That should be good
for CNC also.


I guess what I am suggesting is that it's time for LinuxCNC to be
broken apart and a standardized interface for Ethernet control be
developed.  Once that could talk to dumb FPGA devices like the 7i92H
or to full blown standalone CNC controllers that can act as simple
DRO/Power Feed or even simple G-Code like the 3D printers.  Or be
connected to the much more powerful LinuxCNC to add, in addition to
G-Code the fancy tool changing apparatus along with robotic cells
that load and unload the parts.


You are completely missing the point. You don't need to 'break apart'
LinuxCNC. It is designed from the ground up to be modular. The


'break apart' is architectural change just like it happened to so many
GNU-Linux services or programs. Robotics is one of the closest
functions to CNC. Some robots depend on RT kernel but do not have or
need GUI on top of it.

Medical robotics is the most critical example of a device that needs
to work as planned and programmed. What do they use to write programs
or configure the OS? According to one job posting, INTUITIVE SURGICAL
uses something like:
https://www.openembedded.org/wiki/Main_Page
https://www.yoctoproject.org/

Yocto Project works on any architecture. "...You are not locked down
to any one supplier as Yocto Project is both open source and supports
many architectures" except freaky old parallel port!

"...More and more, these types of devices are prototyped (and
sometimes implemented) with easily available consumer hardware devices
such as the Raspberry Pi or the BeagleBone, or MinnowBoard"


trajectory planner is just another module. Want to run an external
box with it's own TP and I/O? No problem. Write a module to replace
it that talks to your TP and you're off to the races. If you have the
knowledge to write your own 6 axis TP on an external board, writing
the HAL module to talk to it will be a piece of cake.

Les


examples of embedded system customization:
https://wiki.st.com/stm32mpu/wiki/OpenEmbedded
http://wiki.openmoko.org/wiki/OpenEmbedded

To naysayers; there's gold in those hills:
https://www.crunchbase.com/hub/hardware-companies#section-recent-activities

One more comment on application distribution. It's based on my
experience from few years ago where "cloud service" was designed on
Centos distribution. Programs, libraries, and configuration files were
packed as RPMs and installed as such. I proposed much simpler and more
flexible packaging, tar files as in Slackware. The advantage would be
in architecture where more than one version of service could be
installed in parallel without interfering with another one.

Active service would be a link 'from the top directory'. Switching
from one version to another one would be simple:
- service  stop,
- relink top directory,
- service  start.

What we were doing was order pizza, stop services, install RPMs on top
of old ones, start services. That process took about 3 hours on all
servers in the evenings when the network traffic was low 

Re: [Emc-users] How to get 6i25 functioning?

[Andy Pugh]

> On 19 Feb 2020, at 01:27, Ed W  wrote:
> 
> 
> OK, so how do I debug why I don't see any steps coming out..? Hmm. I am 
> really unsure what I should be doing here...

What step length did you choose? Maybe they are just too short for your 
measuring equipment. 

 You can test the card from the command line

halrun
loadrt hostmot2 
loadrt hm2_pci config=“num_stepgens=0”
loadrt threads
addf hm2_5i25.0.read thread1
addf hm2_5i25.0.write thread1
start

You now should have a running but doing nothing 6i25 with the stepgens set up 
as GPIO. To see all the pin names:

show pin
show param

To set the value of a pin so you can measure it

setp hm2_5i25.0.gpio.000.is-output 1
setp hm2_5i25.0.gpio.000.out 1 (or 0)

This uses gpio numbers. But you should have seen a list scroll past during the 
setup stage with the gpio to pin number mapping. 

When you have finished experimenting 

exit

You can use tab-completion and command history to make it quicker, and also to 
ensure correct spelling. And that might be needed as this is all from memory 
and typed on my phone. 

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Re: [Emc-users] Feeds and speeds

[John Dammeyer]

Which factory?

> -Original Message-
> From: andrew beck [mailto:andrewbeck0...@gmail.com]
> Sent: February-18-20 11:46 PM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] Feeds and speeds
> 
> I found the aliexpress and Amazon endmills are just the budget ones.  I pay
> the same price for Chinese cutters that are so much better.  You need to go
> to a factory I found..  Aliexpress sellers are actually putting a premium
> on things as hard as that is to believe.
> 
> And you don't have to use high rpm.  Just hack with them like you normally
> do.
> 
> Only now rpm doesn't matter so much The cutter doesn't care.  It's more
> what the machine can handle
> 
> On Wed, Feb 19, 2020, 7:26 PM John Dammeyer 
> wrote:
> 
> > Amazon.ca has a set of 5 carbide 6mm for $34.29 Cdn.  I imagine that $6.85
> > each isn't too high a price?
> >
> > https://www.amazon.ca/4-Flute-Tungsten-Carbide-Milling-
> Diameter/dp/B07B9PRNWC/ref=sr_1_8?keywords=carbide+end+mill+1%2F4
> =1582092811=8-8
> > John
> >
> >
> > > -Original Message-
> > > From: andrew beck [mailto:andrewbeck0...@gmail.com]
> > > Sent: February-18-20 9:50 PM
> > > To: Enhanced Machine Controller (EMC)
> > > Subject: Re: [Emc-users] Feeds and speeds
> > >
> > > You guys all probably know this but I'll say it anyway..  You should
> > start
> > > using carbide endmills.  I run a tooling company here in New Zealand
> > > selling to the local machine shops.  Carbide is awesome.  Anyway I have a
> > > couple of Chinese suppliers I buy my stuff from and a Taiwanese supplier
> > > for higher quality stuff.  Shout out if you want to find some suppliers
> > and
> > > I'll connect you up.
> > >
> > > On Wed, Feb 19, 2020, 5:12 PM Jon Elson 
> wrote:
> > >
> > > > On 02/18/2020 08:45 PM, John Dammeyer wrote:
> > > > > I've got Mecsoft AlibreCAM generating the tool paths for this in the
> > > > attached photo.  It's Cold Rolled steel 3/16" thick.  I'm using a 1/4"
> > HSS
> > > > end mill.  I'm trying to figure out, using Machinists tool box, exactly
> > > > what feeds and speeds could be used for milling the slot.
> > > > >
> > > > > I was thinking 30 SFM and with a 4 flute end mill doing 0.003" per
> > flute
> > > > the toolbox comes out with  460RPM, 5.5ipm for S460 and F5.5 and 10%
> of
> > > > tool diameter for depth per pass so 0.025"
> > > > >
> > > > > Is that too conservative or likely to break something?  Doing it
> > > > manually I'd do it by feel but once it's automatic it's harder to
> > decide
> > > > SFM and chip load.
> > > > >
> > > > Those numbers sound mostly OK to me.  But, I LONG AGO gave
> > > > up plain HSS, the tool life was just awful.
> > > > I learned on a box of P Stellite tools and got spoiled.
> > > > When I finally wore them out, I started using
> > > > M42 and M57 cutters, which have at least 3X the tool life.
> > > > I'm showing 60-80 SFPM so that would be more
> > > > like 900-1000 RPM, but coolant would be required.  And, I
> > > > usually plunge about 1/2 the cutter diameter
> > > > per pass.  It all depends on the stiffness of your machine
> > > > how much of a cut it can handle.
> > > >
> > > > Jon
> > > >
> > > >
> > > > ___
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> > > > Emc-users@lists.sourceforge.net
> > > > https://lists.sourceforge.net/lists/listinfo/emc-users
> > > >
> > >
> > > ___
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> >
> >
> >
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