[Emc-users] ESR testing [Was: Cute little machine]

[Erik Christiansen]

On an old thread; 08.05.15 05:29, Mark Wendt wrote:
> I bought a little transistor/cap tester kit from Banggood a while back, 

Having followed suit, I was disappointed today to find a new/old-stock
great fat 10,000 uF electrolytic giving an ESR reading of 0.8 ohm.
Being, at least philosophically, Scottish, I thought I'd give reforming
the dielectric a go. (My method is just to put the multimeter on ohms
range, to apply a low voltage at low current. Mine emits + on the
negative terminal in ohms mode, so reverse connection of the leads is
needed.)

When I came back later, the needle had crept up to full scale on ohms x 1,
and after briefly shorting with a screwdriver, just in case, retesting
gave an ESR of 0.03 ohms.

I don't know how typical that improvement might be, but it does show
that a capacitor oughtn't be ruled out at first glance.

Erik

--
Monitor Your Dynamic Infrastructure at Any Scale With Datadog!
Get real-time metrics from all of your servers, apps and tools
in one place.
SourceForge users - Click here to start your Free Trial of Datadog now!
http://pubads.g.doubleclick.net/gampad/clk?id=241902991=/4140
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] near module has me confused

[andy pugh]

On 17 September 2015 at 02:32, Gene Heskett  wrote:
> So what do I set its TOL and SCALE at to achieve this, and better yet,
> how did you go about determining the proper settings to do that?

It's a fairly simple comp, maybe loooking at the source code will help?

http://git.linuxcnc.org/gitweb?p=linuxcnc.git;a=blob;f=src/hal/components/near.comp;h=fd9a62cd787dbd8f5222a52026b0046069c93749;hb=HEAD

read && as "and" and || as "or"

-- 
atp
If you can't fix it, you don't own it.
http://www.ifixit.com/Manifesto

--
Monitor Your Dynamic Infrastructure at Any Scale With Datadog!
Get real-time metrics from all of your servers, apps and tools
in one place.
SourceForge users - Click here to start your Free Trial of Datadog now!
http://pubads.g.doubleclick.net/gampad/clk?id=241902991=/4140
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] ESR testing [Was: Cute little machine]

[Mark Wendt]

On Thu, Sep 17, 2015 at 5:09 AM, Erik Christiansen
 wrote:
> On an old thread; 08.05.15 05:29, Mark Wendt wrote:
>> I bought a little transistor/cap tester kit from Banggood a while back,
>
> Having followed suit, I was disappointed today to find a new/old-stock
> great fat 10,000 uF electrolytic giving an ESR reading of 0.8 ohm.
> Being, at least philosophically, Scottish, I thought I'd give reforming
> the dielectric a go. (My method is just to put the multimeter on ohms
> range, to apply a low voltage at low current. Mine emits + on the
> negative terminal in ohms mode, so reverse connection of the leads is
> needed.)
>
> When I came back later, the needle had crept up to full scale on ohms x 1,
> and after briefly shorting with a screwdriver, just in case, retesting
> gave an ESR of 0.03 ohms.
>
> I don't know how typical that improvement might be, but it does show
> that a capacitor oughtn't be ruled out at first glance.
>
> Erik

I haven't checked my transistor/cap tester against a real ESR meter I
have for my bench, so I don't know how accurate it is at that.  My
electronics stuff is all packed up right now, waiting to be put in the
moving van, so I won't have a chance to play for a while.

We close on October 15th (hopefully), and then I put Washington DC in
the rear view mirror.

Mark



-- 
One Man, One Machine, One Computer!  

--
Monitor Your Dynamic Infrastructure at Any Scale With Datadog!
Get real-time metrics from all of your servers, apps and tools
in one place.
SourceForge users - Click here to start your Free Trial of Datadog now!
http://pubads.g.doubleclick.net/gampad/clk?id=241902991=/4140
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] ESR testing [Was: Cute little machine]

[Erik Christiansen]

On 17.09.15 05:54, Mark Wendt wrote:
> I haven't checked my transistor/cap tester against a real ESR meter I
> have for my bench, so I don't know how accurate it is at that.  My
> electronics stuff is all packed up right now, waiting to be put in the
> moving van, so I won't have a chance to play for a while.

For a quick reality check, I just wired a 1 ohm wirewound power resistor
in series with the cap. Now it reads 1.2 ohms. With resistor tolerance
and inductance, that's not too far off. Adding instead, a 0.02 ohm 1%
non-wirewound, the reading jumps from 0.05 to 0.17 ohm. My lead clips
are not making zero ohm connections. Just the leads and resistor reads
0.1 ohms. And yet it repeatedly gives 0.03 to 0.05 ohms for the
capacitor ESR.

There's no elaborate precision analogue circuitry in the thing, so we
can't hope for more than an approximate result. For me, it is enough
that it discriminates between 0.8 ohms and 0.05, and whether that 0.05
is really 0.03 or 0.07 is no biggie.

> We close on October 15th (hopefully), and then I put Washington DC in
> the rear view mirror.

That's the strongest reaction I've yet heard to the prospect of "The
Donald" maybe heading into town after the incumbent leaves.

Erik

-- 
Bureaucrat behind desk: "You need a planning permit to continue farming"
Aussie farmer: "I need my head read if I want to continue farming"
- Chris Rule cartoon in the Weekly Times, 05.08.15

--
Monitor Your Dynamic Infrastructure at Any Scale With Datadog!
Get real-time metrics from all of your servers, apps and tools
in one place.
SourceForge users - Click here to start your Free Trial of Datadog now!
http://pubads.g.doubleclick.net/gampad/clk?id=241902991=/4140
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] ESR testing [Was: Cute little machine]

[Gene Heskett]

On Thursday 17 September 2015 05:09:07 Erik Christiansen wrote:

> On an old thread; 08.05.15 05:29, Mark Wendt wrote:
> > I bought a little transistor/cap tester kit from Banggood a while
> > back,
>
> Having followed suit, I was disappointed today to find a new/old-stock
> great fat 10,000 uF electrolytic giving an ESR reading of 0.8 ohm.
> Being, at least philosophically, Scottish, I thought I'd give
> reforming the dielectric a go. (My method is just to put the
> multimeter on ohms range, to apply a low voltage at low current. Mine
> emits + on the negative terminal in ohms mode, so reverse connection
> of the leads is needed.)
>
> When I came back later, the needle had crept up to full scale on ohms
> x 1, and after briefly shorting with a screwdriver, just in case,
> retesting gave an ESR of 0.03 ohms.
>
> I don't know how typical that improvement might be, but it does show
> that a capacitor oughtn't be ruled out at first glance.
>
> Erik
>
And as a CET, and an old hand at that, thats a capacitor that would go in 
the bin Erik.  And its not open for discussion around my workbench.

The fact that you shorted it while charged with only the meters volt or 
so charge, and "fixed" it, which punches thru the foil oxides and 
restores a good but temporary connection, making that cap look good 
again, also says it will be bad again quick enough to eat your warranty 
budget.

Making a good, very low resistance connection between the external 
terminal metal, normally made out of something solderable like copper, 
and the alu foils that make up the capacitors  "plates" is a high art 
form because the alu is so reactive with the oxygen in the air we 
breath.  Throw in that it is etched chemically to increase its surface 
area 10 to 50 fold over plain alu, which increases its capacitance by 
the same factor, and you can begin to imagine the difficulty in actually 
getting a "gas tight" joint between the terminal and the alu foils.  The 
lack of that says the ESR will rise to the failure point in a relatively 
short time.  In low power stuff, the circuit will just mis-behave.  In 
higher powered situations, the heating from the ESR will eventually blow 
the caps case top open, or causing bulging of it before.

When inspecting any circuit that uses electrolytic capacitors, seeing any 
of them with bulged tops, is grounds to warm up the iron & replace them.  
They have already failed in terms of their ESR.

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)
Genes Web page 

--
Monitor Your Dynamic Infrastructure at Any Scale With Datadog!
Get real-time metrics from all of your servers, apps and tools
in one place.
SourceForge users - Click here to start your Free Trial of Datadog now!
http://pubads.g.doubleclick.net/gampad/clk?id=241902991=/4140
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] ESR testing [Was: Cute little machine]

[Mark Wendt]

On Thu, Sep 17, 2015 at 8:48 AM, Erik Christiansen
 wrote:
> On 17.09.15 05:54, Mark Wendt wrote:
>> I haven't checked my transistor/cap tester against a real ESR meter I
>> have for my bench, so I don't know how accurate it is at that.  My
>> electronics stuff is all packed up right now, waiting to be put in the
>> moving van, so I won't have a chance to play for a while.
>
> For a quick reality check, I just wired a 1 ohm wirewound power resistor
> in series with the cap. Now it reads 1.2 ohms. With resistor tolerance
> and inductance, that's not too far off. Adding instead, a 0.02 ohm 1%
> non-wirewound, the reading jumps from 0.05 to 0.17 ohm. My lead clips
> are not making zero ohm connections. Just the leads and resistor reads
> 0.1 ohms. And yet it repeatedly gives 0.03 to 0.05 ohms for the
> capacitor ESR.
>
> There's no elaborate precision analogue circuitry in the thing, so we
> can't hope for more than an approximate result. For me, it is enough
> that it discriminates between 0.8 ohms and 0.05, and whether that 0.05
> is really 0.03 or 0.07 is no biggie.

Yeah, I figured that.  I bought the thing mainly for the quick and
dirty transistor/diode checking.  If I really want to get into
profiling transistors or diodes, I've got a Tek 577 Curve Tracer to do
that.  I've mainly used the tester just to get decent capacitance
readings on the cap side of the house.  I've got a really good ESR
that I use to really check electrolytics.

>
>> We close on October 15th (hopefully), and then I put Washington DC in
>> the rear view mirror.
>
> That's the strongest reaction I've yet heard to the prospect of "The
> Donald" maybe heading into town after the incumbent leaves.
>
> Erik

Eh, he couldn't do any worse than the clowns that currently occupy DC.

Mark

-- 
One Man, One Machine, One Computer!  

--
Monitor Your Dynamic Infrastructure at Any Scale With Datadog!
Get real-time metrics from all of your servers, apps and tools
in one place.
SourceForge users - Click here to start your Free Trial of Datadog now!
http://pubads.g.doubleclick.net/gampad/clk?id=241902991=/4140
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Lathe cutting forces

[Ed]

On 09/17/2015 07:57 AM, andy pugh wrote:
> To size motors, screws, bearings etc for my CNC lathe conversion I
> have been trying to find cutting force data.
>
> http://www.ijera.com/papers/Vol4_issue4/Version%201/U044134144.pdf
>
> Seems to say that a feed force of 100N is about normal.
> This seems rather less than I would have guessed.
>
> Does anyone else have any feel for this. I have been designing around
> 2kN, and I know that many CNC lathes have multi-kW Z servos.
>
Many CNC lathes push large twist drills and spade drills through some 
tough material. How big do you plan?

Ed.


--
Monitor Your Dynamic Infrastructure at Any Scale With Datadog!
Get real-time metrics from all of your servers, apps and tools
in one place.
SourceForge users - Click here to start your Free Trial of Datadog now!
http://pubads.g.doubleclick.net/gampad/clk?id=241902991=/4140
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Lathe cutting forces

[Rick Lair]

I know that our big machines have 7.5 kw Z axis motors, and 3.5 kw X 
axis motors.


On 9/17/2015 8:57 AM, andy pugh wrote:
> To size motors, screws, bearings etc for my CNC lathe conversion I
> have been trying to find cutting force data.
>
> http://www.ijera.com/papers/Vol4_issue4/Version%201/U044134144.pdf
>
> Seems to say that a feed force of 100N is about normal.
> This seems rather less than I would have guessed.
>
> Does anyone else have any feel for this. I have been designing around
> 2kN, and I know that many CNC lathes have multi-kW Z servos.
>

-- 

Thanks


Rick Lair
Superior Roll & Turning LLC
399 East Center Street
Petersburg MI, 49270
PH: 734-279-1831
FAX: 734-279-1166
www.superiorroll.com


--
Monitor Your Dynamic Infrastructure at Any Scale With Datadog!
Get real-time metrics from all of your servers, apps and tools
in one place.
SourceForge users - Click here to start your Free Trial of Datadog now!
http://pubads.g.doubleclick.net/gampad/clk?id=241902991=/4140
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] Lathe cutting forces

[andy pugh]

To size motors, screws, bearings etc for my CNC lathe conversion I
have been trying to find cutting force data.

http://www.ijera.com/papers/Vol4_issue4/Version%201/U044134144.pdf

Seems to say that a feed force of 100N is about normal.
This seems rather less than I would have guessed.

Does anyone else have any feel for this. I have been designing around
2kN, and I know that many CNC lathes have multi-kW Z servos.

-- 
atp
If you can't fix it, you don't own it.
http://www.ifixit.com/Manifesto

--
Monitor Your Dynamic Infrastructure at Any Scale With Datadog!
Get real-time metrics from all of your servers, apps and tools
in one place.
SourceForge users - Click here to start your Free Trial of Datadog now!
http://pubads.g.doubleclick.net/gampad/clk?id=241902991=/4140
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Lathe cutting forces

[Erik Christiansen]

On 17.09.15 08:36, Ed wrote:
> On 09/17/2015 07:57 AM, andy pugh wrote:
> > Seems to say that a feed force of 100N is about normal.
> > This seems rather less than I would have guessed.
> >
> > Does anyone else have any feel for this. I have been designing around
> > 2kN, and I know that many CNC lathes have multi-kW Z servos.
> >
> Many CNC lathes push large twist drills and spade drills through some 
> tough material. How big do you plan?

There's also a hefty carriage with a massive tool turret and motor to
accelerate at dollar-earning rates, plus bed friction to overcome, in
many cases. As well, the DOC and FPR in table 4 do not look much like
production roughing cuts with TC tooling and flood coolant.

The knurling gcode from earlier in the week would also require higher
feed force than the feed of 180 microns per rev in table 4, I figure.

Erik

--
Monitor Your Dynamic Infrastructure at Any Scale With Datadog!
Get real-time metrics from all of your servers, apps and tools
in one place.
SourceForge users - Click here to start your Free Trial of Datadog now!
http://pubads.g.doubleclick.net/gampad/clk?id=241902991=/4140
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Lathe cutting forces

[andy pugh]

On 17 September 2015 at 14:36, Ed  wrote:
> Many CNC lathes push large twist drills and spade drills through some
> tough material. How big do you plan?

My current lathe has stepper motors, and stalls if asked to push a big
drill, so in fact my 2kN number was derived from asking FS-Wizard what
the push force was an a 25mm drill.

However, when pushing a big drill I am not as concerned about Z axis
acurracy. I was looking for numbers to plug in to FEA calcs of my Z
bearing housing design.
This is an interesting puzzle, as there are advantages in keeping it
compact to keep the screw/nut as close to the work as possible.

-- 
atp
If you can't fix it, you don't own it.
http://www.ifixit.com/Manifesto

--
Monitor Your Dynamic Infrastructure at Any Scale With Datadog!
Get real-time metrics from all of your servers, apps and tools
in one place.
SourceForge users - Click here to start your Free Trial of Datadog now!
http://pubads.g.doubleclick.net/gampad/clk?id=241902991=/4140
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] ESR testing [Was: Cute little machine]

[Erik Christiansen]

On 17.09.15 09:39, Gene Heskett wrote:
> On Thursday 17 September 2015 05:09:07 Erik Christiansen wrote:
> The fact that you shorted it while charged with only the meters volt or 
> so charge, and "fixed" it, which punches thru the foil oxides and 
> restores a good but temporary connection, making that cap look good 
> again, also says it will be bad again quick enough to eat your warranty 
> budget.

It is reforming the dielectric which was performed. It deteriorates
during prolonged disuse, and can be regenerated by applying a low
voltage at a modest current. Discharging the capacitor was merely to
avoid risk to the tester electronics afterwards, nothing else.

OK, a weak dielectric manifests primarily as increased leakage (shunt
resistance) and susceptibility to failure at less than full voltage,
suddenly applied. The effect on series resistance is harder to qualify.

> Making a good, very low resistance connection between the external 
> terminal metal, normally made out of something solderable like copper, 
> and the alu foils that make up the capacitors  "plates" is a high art 
> form because the alu is so reactive with the oxygen in the air we 
> breath.  Throw in that it is etched chemically to increase its surface 
> area 10 to 50 fold over plain alu, which increases its capacitance by 
> the same factor, and you can begin to imagine the difficulty in actually 
> getting a "gas tight" joint between the terminal and the alu foils.

Not a lot of imagination needed. The big aluminium electrolytics I've
examined over the years had plain aluminium strip which looked to be
welded to the etched plates (prior to etching, I expect.) and also to
the terminals.

In this case, the terminals are aluminium posts, internally threaded.
The internal terminal connection, presumably also welded, isn't going to
experience oxidation, I suggest.

In any event, the resistance of an unetched oxide layer on aluminium
ought not be overestimated. Whether the mechanism is electron tunnelling
or not, the massive current which flowed through two series oxide layers
on the outside terminals, with only a volt or two, confirms at high
current what an ohmmeter shows on placing two probes on an aluminium
surface - at least an order of magnitude less than my 0.02 ohm resistor.

Most of the ESR is in the electrolyte, AIUI.

Erik

--
Monitor Your Dynamic Infrastructure at Any Scale With Datadog!
Get real-time metrics from all of your servers, apps and tools
in one place.
SourceForge users - Click here to start your Free Trial of Datadog now!
http://pubads.g.doubleclick.net/gampad/clk?id=241902991=/4140
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] near module has me confused

[Gene Heskett]

On Thursday 17 September 2015 10:44:07 Gene Heskett wrote:

> Thanks for the link Andy, thats very helpful.  I'll have to play with
> a calculator of course, some of which you see above, but now I have a
> clue as to what the heck i am doing rather than blindly trying numbers
> for effect.
>
> Cheers, Gene Heskett

I wound up with stuff in the ballpark of what I wrote, a 5 rpm difference 
at zero speed, and scaled up by 1.1 as the speeds rise.

But I have a secondary problem still,  With a limit3 with a maxa setting 
in front of the pid.s.command, no matter what I do with the maxa 
setting, which does control the speed it responds to an m3-m4-m3 
transition, it always overshoots to about 1.4x the set speed as it winds 
up in the new direction, even if I set maxa so low it takes a very 
leasurely 10 seconds to turn it around.  The overshoot appears to be the 
same magnitude regardless of the speed of the turnaround.

But it seems to me that at a speed change rate of accel slow enough the 
pid has total control, there should not be any overshoot, but something 
sure seems to be getting wound up & has to be unwound before it settles.

Does this ring any bells?  Increased Dgain seems to help, but also seems 
to make the whole thing sing at about the 1KHz servo-thread frequency.

Thanks for any clues, or links to PID tuning tuts more detailed than the 
single paragraph in the new 2.7 document pdf. This is not a position 
servo, but a velocity, and most tuts I can google seem to position mode.

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)
Genes Web page 

--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] CAD/CAM for LinuxCNC

[John Dammeyer]

Hi,
I've been using Alibre (now Geomagic) and the VisualCAM plugin for
generating G-Code.  MecSoft will no longer be supporting the plugin and has
offered a standalone version of VisualCAM.  When 3D Systems purchased Alibre
I wondered whether it would eventually just become a CAD system for rapid
prototyping.  I suspect that will happen soon.

So with MACH3 turning into a networked licensed (must be internet connected)
CNC system and Geomagic no longer having an integrated CAM interface it
seems like it's a good time to re-evaluate LinuxCNC and for that matter
Linux for the entire development process.  That or live with WIN-10 (GACK)

So what are people using for the 3D parametric drawing to G-Code CAM
generation to the LinuxCNC control?

Or is Linux still in the 2D drawing world with a post processor to generate
G-Code that needs the command line editor VI to clean up?
John



--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] CAD/CAM for LinuxCNC

[Jason Burton]

Fusion 360 CAM is very nice.

On Thu, Sep 17, 2015 at 11:49 PM, John Dammeyer 
wrote:

> Hi,
> I've been using Alibre (now Geomagic) and the VisualCAM plugin for
> generating G-Code.  MecSoft will no longer be supporting the plugin and has
> offered a standalone version of VisualCAM.  When 3D Systems purchased
> Alibre
> I wondered whether it would eventually just become a CAD system for rapid
> prototyping.  I suspect that will happen soon.
>
> So with MACH3 turning into a networked licensed (must be internet
> connected)
> CNC system and Geomagic no longer having an integrated CAM interface it
> seems like it's a good time to re-evaluate LinuxCNC and for that matter
> Linux for the entire development process.  That or live with WIN-10 (GACK)
>
> So what are people using for the 3D parametric drawing to G-Code CAM
> generation to the LinuxCNC control?
>
> Or is Linux still in the 2D drawing world with a post processor to generate
> G-Code that needs the command line editor VI to clean up?
> John
>
>
>
>
> --
> ___
> 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

Re: [Emc-users] CAD/CAM for LinuxCNC

[John Dammeyer]

> -Original Message-
> From: Jason Burton [mailto:lathebuil...@gmail.com]
> Sent: September-17-15 10:08 PM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] CAD/CAM for LinuxCNC
> 
> 
> Fusion 360 CAM is very nice.
> 

I went to the web site and tried to download from Debian.
"Your operating system is not supported. Fusion 360 is supported on 64-bit
Windows 7 or newer and 64-bit Mac OS X 10.9 or newer."

>From the web site:
"Fusion 360T is the first 3D CAD/CAM tool of its kind, connecting your
entire product development process in a single cloud-based tool."

Cloud based implies permanently connected to the internet right?  That's a
non-starter for the same reason MACH4 is a non-starter.

I realize I may sound rather odd when I say this but think about it.  Walk
up to your 1942 South Bend lathe and you can turn out metal parts.  

Surf just about any forum on the internet more than 1 year old and click on
links that end up with a 404 not found error.  Support cloud computing and
buy into the deal that next year it will cost you again or it won't be
available at all.

John



--
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users