Re: [Emc-users] Spindle soft start

[Andy Ibbotson]

Ok, I'm still trying to setup my scaling in PDM mode.  I have a base period 
of 3ns and need to configure pwmgen to gove a 2kHz outout for a 
commanded spindle speed of 4000rpm - equation to 10V output from my DAC. 
Assuming no offsets is there a method for calcuating pwmgen.N.scale ?  or is 
it a trial and error approach.  At present a value of 20.0 produces an 
ouput close to what I need but this seems a "big" number.  Any help will be 
very appreciated.
Many thanks
Andy
- Original Message - 
From: "Jeff Epler" 
To: "Enhanced Machine Controller (EMC)" 
Sent: Saturday, September 26, 2009 1:19 PM
Subject: Re: [Emc-users] Spindle soft start


> On Sat, Sep 26, 2009 at 08:36:13AM +0100, Andy I wrote:
>> Hi Everyone,
>> Is this mail getting through??
>
> Yes.
>
>>
>> I have an X2 mill with a spindle controller which converts pulses to
>> voltage output.  I'm planning to use pwmgen in PDM mode to generate the
>> pulses.  Is there a way to ramp up the pulse density (frequency) to
>> allow a soft spindle start?
>
> One way is to use a 'limit2' block between motion.spindle-speed-cmd and
> whatever is making the pulses.  limit2.#.maxv limits the rate at which
> the output signal changes to track the input.  For example, if you set
> it to 60, and the input is revolutions per second, then it will take 1
> second to ramp up from 0RPM to 60RPM or down from 60RPM to 0RPM.
>
> At the same time, you'll probably want to start using the
> spindle-at-speed input so that emc waits for the spindle to reach the
> commanded speed before cutting.  This involves a 'near2' block with its
> output going to motion.spindle-at-speed, one input coming from the
> motion.spindle-speed-cmd, and the other coming from the current spindle
> speed.  If you have spindle feedback, then you'd use that.  Otherwise,
> you'd use the limit2 output as a proxy for current spindle speed (since
> it's changing slow enough that the spindle can track it accurately)
>
> Jeff
>
> --
> Come build with us! The BlackBerry® Developer Conference in SF, CA
> is the only developer event you need to attend this year. Jumpstart your
> developing skills, take BlackBerry mobile applications to market and stay
> ahead of the curve. Join us from November 9-12, 2009. Register 
> now!
> http://p.sf.net/sfu/devconf
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users 


--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] feed hold in MDI

[Chris Morley]

>I have feedback from the spindle drive to tell the machine when the
> spindle drive has an error. I need to incorporate that into ladder also. I
> want the machine to go into feed hold when the spindle drive errors.
> thanks
> Stuart
> 

I think we need to add a non maskable motion hold pin to EMC
Feed hold works but can be masked. Having a separate
pin from feed hold would keep the logic cleaner.

There has been a couple times I have noted this need.
I don't imagine it would take a lot of coding either.

Cheers Chris M
 
  
_
We are your photos. Share us now with Windows Live Photos.
http://go.microsoft.com/?linkid=9666047
--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Engrave.py cuts deeper and deeper

[Jon Elson]

Jon Elson wrote:
> Sven Wesley wrote:
>   
>> I can cannot see any changes in speed even if I push put all my body weight
>> on the Z-axis, it just runs super easy and the motors never gets warm. It
>> doesn't _seem_ to be a force/power problem.
>> I have put so much money and time in building a servo system. It's REALLY
>> annoying if I have to go back to steppers. To me, these eBay-items looks
>> pretty small too. Are they really going to make it?
>>   
>> 
> I am now CONVINCED that your problem is a step timing issue, possibly a 
> step-vs-direction
> setup time issue.  I am also sure the Rutex has some kind of a fault 
> output, but you may not be using it.
> I remember the fault window is programmable, as opposed to Gecko's fixed 
> limit.
>   
Hmmm, I just saw a bug report on the developer list that may have 
something to do
with this problem :

Bugs item #2870131, was opened at 2009-09-29 23:23
Message generated for change (Tracker Item Submitted) made by svenakela
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=106744&aid=2870131&group_id=6744

Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: Stepconf
Group: None
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: Sven  (svenakela)
Assigned to: Jeff Epler (jepler)
Summary: Direction setup doesn't change

Initial Comment:
When setting a new value for Direction setup in an existing configuration the 
new value is never used.
It's reproducable: Change the value and then click "forward". Then click "back" 
to go back to the same view and the old value will be there.
If the stepconf config is saved the old value will remain when restarting 
Stepconf.

The only way to set the value is to manually edit the Stepconf XML before 
starting the wizard. 

This is in release 2.3.3



--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] feed hold in MDI

[Stuart Stevenson]

Jon,
   I have a pulse generator tied to the slider bar. When I turn the feed
down the slides stop.
   I want the feed hold button to stop the feed immediately (like it does
when running the program).
   I have the feed hold button working through a classic ladder program. I
will work to incorporate that for the MDI also.
   I have feedback from the spindle drive to tell the machine when the
spindle drive has an error. I need to incorporate that into ladder also. I
want the machine to go into feed hold when the spindle drive errors.
thanks
Stuart

On Tue, Sep 29, 2009 at 9:05 PM, Jon Elson  wrote:

> Stuart Stevenson wrote:
> > Gentlemen,
> >I need feed hold to work in MDI. Is that a lot of work? Is it
> something I
> > can try to do (with help and guidance)?
> >
> If you set up some kind of external (non-keyboard) control for feed
> override, that will
> work as EMC exists, now.  Do you have a spare encoder input?  I see
> where some people
> have rigged their jog pendant encoder so that instead of just selecting
> axes to jog, you could
> also control feed override and spindle speed override from the jog encoder.
>
> Otherwise, dragging the slider bar on Axis with the mouse "should" still
> work even when
> in MDI (or do those sliders disappear when in the MDI screen?)
>
>
> Jon
>
>
> --
> Come build with us! The BlackBerry® Developer Conference in SF, CA
> is the only developer event you need to attend this year. Jumpstart your
> developing skills, take BlackBerry mobile applications to market and stay
> ahead of the curve. Join us from November 9-12, 2009. Register now!
> http://p.sf.net/sfu/devconf
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>
>


-- 
you can lead a person to knowledge
but you cannot make him think
--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Encoders

[Jon Elson]

Andy Pugh wrote:
> My system seems to track a 50-line encoder adequately, would that
> nromally be considered enough resolution for threading?
>   
50 lines is 200 quadrature counts, should be fine for threading, I would 
think.
That is a unique position reading for every 360/200 = 1.8 degrees of 
rotation.

Jon

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Encoders

[Jon Elson]

Andy Pugh wrote:
> (Sorry to start yet another thread on much the same subject, but this
> is a bit broader-ranging)
>
> It seems that spindle-synchronised motion is very sensitive to encoder
> regularity.
>
> Using the p-port to read the encoder position means that as the
> encoder linecount goes up, quantisation error in the measured
> positions also goes up, and so the inter-line period noise increases.
> Does this mean then, that very low linecounts will give less dither,
> and better results?
>   
Apparently not.  I am using an encoder with 1728 cycles/rev, or 6912 
quadrature
counts/rev.  It works fine, although some improvements in EMC2 that were 
made
last year were quite helpful.  Also, it is quite important that the 
trajectory planner
be running at the servo update rate, and not the typical 5X slower rate 
that was used
in earlier versions of EMC2.
> http://www.pastebin.ca/1583502
> Is the raw halscope data from my machine. If you plot the encoder
> position it looks dead straight, but the raw data shows that the
> difference between successive samples is quite variable.
>   
The last column seems to show wide variations, indicating maybe the 
sampling is missing
complete revolutions.  Lines 7 and 19 show such a large variation, for 
instance.
This may be due to noise in the signal, too.  This is the reason I 
strongly advise people,
OVER and OVER, to not try to use software sampling of such signals.

> Is this possibly the reason that my attempts at threading are so hopeless?
>
> I would be the first to admit that my encoder is rubbish, it is a bit
> of computer-printed paper wrapped round the lathe spindle, but even if
> I was to get a high-accuracy encoder disc I feel I would still be at
> the mercy of sample quantisation errors
> Any opinions on the best way forwards?
I really don't think it is the encoder, but can't be sure.  If the 
sensor sees a lot of
light near the decision threshold, it may be flickering on and off 
instead of solidly sending
ON, then OFF, then back to ON at the right times.  If it is flickering 
during periods when
it should be sensing a solid on or off, the software will sample the 
wrong thing.  You really
need an oscilloscope, but you might be able to see enough in HalScope to 
determine what
it is doing.


Jon

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] feed hold in MDI

[Jon Elson]

Stuart Stevenson wrote:
> Gentlemen,
>I need feed hold to work in MDI. Is that a lot of work? Is it something I
> can try to do (with help and guidance)?
>   
If you set up some kind of external (non-keyboard) control for feed 
override, that will
work as EMC exists, now.  Do you have a spare encoder input?  I see 
where some people
have rigged their jog pendant encoder so that instead of just selecting 
axes to jog, you could
also control feed override and spindle speed override from the jog encoder.

Otherwise, dragging the slider bar on Axis with the mouse "should" still 
work even when
in MDI (or do those sliders disappear when in the MDI screen?)


Jon

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Encoders

[Andy Pugh]

2009/9/29 Kirk Wallace :

> I still think your threading problem is due to the Z acceleration issue.
> You may try cutting an air thread that is as long as your Z axis will
> allow. If your thread wanders the same across the thread then I would
> look into your encoder more. If the wander settles to a perfect sync to
> your spindle, then look at the accel problem.

As always, it is more complicated than this...

G61.1 helps, but only if I turn down my max accel rate, otherwise it
drives the stepper too fast and it stalls. It is not a complete
solution, either.

I almost managed to cut (another) thread in my component (on the basis
that only I will ever use it, as long as there is one good thread it
will work)by giving it 2" run-up and tweaking the spindle speed
for max stability, but it only takes one dodgy run, and it gouges,
stalls, and messes up utterly. And it did.
Sometimes is settles perfectly adequately, and sometimes it just goes wild.

There is clearly too much dither in the current encoder, I will make
another one.

It does look like more axis acceleration would help, but I have it
turned up to the point where I can't home, and it is still not
responsive enough.

I am slightly confused about the difference between MAXACCELL and
STEPGENMAXACCELL, does anyone know what does what? I found that with
G61.1, MAXACCELL = 300 and STEPGENMAXACELL = 1000 (!) I could almost
use it, but then it stalled the stepper mid cut...

I am pretty much convinced that if I could get to the controller
parameters that handle the synch between spindle and axis I could tune
it to work with my current max accell. It isn't like the machine is
horribly sluggish, 300mm/s/s is enough to get up to top speed (and
twice the speed needed for threading) in 1mm.

-- 
atp

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] feed hold in MDI

[Stuart Stevenson]

Gentlemen,
   If it is a matter of hal configuration I am a happy camper. I will work
on it and report what I find. I need to do some ladder work anyway.
thanks
Stuart


On Tue, Sep 29, 2009 at 2:42 PM, Alex Joni  wrote:

> That should work using the hal pin from the motion controller.
> Feed override -> 0 should also do the trick.
>
> Regards,
> Alex
>
>
> --
> From: "Stuart Stevenson" 
> Sent: Tuesday, September 29, 2009 9:06 PM
> To: "EMC2-Users-List" 
> Subject: [Emc-users] feed hold in MDI
>
> > Gentlemen,
> >   I need feed hold to work in MDI. Is that a lot of work? Is it something
> > I
> > can try to do (with help and guidance)?
> > thanks
> > Stuart
> >
> > --
> > you can lead a person to knowledge
> > but you cannot make him think
> >
> --
> > Come build with us! The BlackBerry® Developer Conference in SF, CA
> > is the only developer event you need to attend this year. Jumpstart your
> > developing skills, take BlackBerry mobile applications to market and stay
> > ahead of the curve. Join us from November 9-12, 2009. Register
> > now!
> > http://p.sf.net/sfu/devconf
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
>
>
>
> >
> > No virus found in this incoming message.
> > Checked by AVG - www.avg.com
> > Version: 8.5.409 / Virus Database: 270.13.114/2402 - Release Date:
> > 09/29/09 05:54:00
> >
>
>
> --
> Come build with us! The BlackBerry® Developer Conference in SF, CA
> is the only developer event you need to attend this year. Jumpstart your
> developing skills, take BlackBerry mobile applications to market and stay
> ahead of the curve. Join us from November 9-12, 2009. Register now!
> http://p.sf.net/sfu/devconf
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>
>


-- 
you can lead a person to knowledge
but you cannot make him think
--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] feed hold in MDI

[Alex Joni]

That should work using the hal pin from the motion controller.
Feed override -> 0 should also do the trick.

Regards,
Alex


--
From: "Stuart Stevenson" 
Sent: Tuesday, September 29, 2009 9:06 PM
To: "EMC2-Users-List" 
Subject: [Emc-users] feed hold in MDI

> Gentlemen,
>   I need feed hold to work in MDI. Is that a lot of work? Is it something 
> I
> can try to do (with help and guidance)?
> thanks
> Stuart
>
> -- 
> you can lead a person to knowledge
> but you cannot make him think
> --
> Come build with us! The BlackBerry® Developer Conference in SF, CA
> is the only developer event you need to attend this year. Jumpstart your
> developing skills, take BlackBerry mobile applications to market and stay
> ahead of the curve. Join us from November 9-12, 2009. Register 
> now!
> http://p.sf.net/sfu/devconf
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users



>
> No virus found in this incoming message.
> Checked by AVG - www.avg.com
> Version: 8.5.409 / Virus Database: 270.13.114/2402 - Release Date: 
> 09/29/09 05:54:00
> 

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] feed hold in MDI

[Chris Radek]

On Tue, Sep 29, 2009 at 01:06:32PM -0500, Stuart Stevenson wrote:
> Gentlemen,
>I need feed hold to work in MDI. Is that a lot of work? Is it something I
> can try to do (with help and guidance)?


Do you mean feed hold a.k.a. "pause" in the GUI and/or halui, or do you
mean the realtime feed hold HAL pin input to motion, motion.feed-hold?

I suspect the latter works already.  The former looks like a GUI issue
only; the task code seems to accept EMC_TASK_PLAN_PAUSE and
EMC_TASK_PLAN_RESUME during an MDI command and it does the right thing.
It looks like halui will even send it for you (halui.program.pause,
halui.program.resume).


--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Encoders

[Gene Heskett]

On Tuesday 29 September 2009, Andy Pugh wrote:
>2009/9/29 Dave Caroline :
>> do you need one of use to make/cut a disk
>
>My machine has a milling head and a 4th axis, so making my own is
>fairly straightforward (But thanks for the offer).
>However I run the risk of doing a lot of machining and still having
>exactly the same problems if it turns out that the paper encoder is
>adequate and that the problem is elsewhere, or if I choose my encoder
>resolution unwisely.
>
>The simplest solution would be to machine a series of slots in the
>lathe spindle drive pulley face, I think. (my encoder uses reflective
>sensors, I just need to check that there is enough contrast between
>cast-iron and no cast-iron.
>
This is where the oscilloscope comes in, you can watch it and know for sure.

>My system seems to track a 50-line encoder adequately, would that
>nromally be considered enough resolution for threading?

-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
The NRA is offering FREE Associate memberships to anyone who wants them.


To find a friend one must close one eye; to keep him -- two.
-- Norman Douglas

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] feed hold in MDI

[Stuart Stevenson]

Gentlemen,
   I need feed hold to work in MDI. Is that a lot of work? Is it something I
can try to do (with help and guidance)?
thanks
Stuart

-- 
you can lead a person to knowledge
but you cannot make him think
--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Encoders

[Kirk Wallace]

On Tue, 2009-09-29 at 17:43 +0100, Andy Pugh wrote:
> 2009/9/29 Dave Caroline :
> >
> > do you need one of use to make/cut a disk
> 
> My machine has a milling head and a 4th axis, so making my own is
> fairly straightforward (But thanks for the offer).
> However I run the risk of doing a lot of machining and still having
> exactly the same problems if it turns out that the paper encoder is
> adequate and that the problem is elsewhere, or if I choose my encoder
> resolution unwisely.
> 
> The simplest solution would be to machine a series of slots in the
> lathe spindle drive pulley face, I think. (my encoder uses reflective
> sensors, I just need to check that there is enough contrast between
> cast-iron and no cast-iron.
> 
> My system seems to track a 50-line encoder adequately, would that
> nromally be considered enough resolution for threading?

My guess is that a fifty line (200 pulses per rev) should be plenty. The
spindle doesn't usually change speed very quickly so you can put your
counting function in the servo thread, or maybe create a slower thread,
which will allow many pulses to be counted per thread cycle. This will
average out a lot of encoder jitter, if there is any. The more counts
per cycle, the better, so you can get better resolution at very slow
speeds, but watch out for the high end pulse rate, which I think you
addressed already. 

With HALscope, you may have to run the scope at the base rate to see the
jitter from your encoder.

I still think your threading problem is due to the Z acceleration issue.
You may try cutting an air thread that is as long as your Z axis will
allow. If your thread wanders the same across the thread then I would
look into your encoder more. If the wander settles to a perfect sync to
your spindle, then look at the accel problem.

Hopefully, someone will correct any errors I have made above.
-- 
Kirk Wallace
http://www.wallacecompany.com/machine_shop/
http://www.wallacecompany.com/E45/index.html
California, USA


--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] G76 Threading

[Andy Pugh]

2009/9/29 Kirk Wallace :

> I have only read the original post and watched the video, so I may be
> off base here. I had the same symptoms on my lathe. I believe the thread
> pitch and spindle RPM are at a rate that is beyond the Z axis abilities
> to accelerate. I slowed my spindle RPM down and allowed for a fair
> amount of air cutting to allow Z to stabilize before reaching the real
> threading.

I have tried as low as 50 rpm (where there probably isn't enough
torque to actually cut) and things are marginally better, but still
not good enough to thread.

>  I also tried to optimize my acceleration settings. Too high
> of an acceleration number created following errors, so it's a
> compromise.

My z-accel is as fast as it can be, tuned in stepconf.

-- 
atp

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Mcode scripting ??

[robert]

VMAXEmbarq wrote:
> Does EMC support this type of function ? From the user manual it seems that 
> EMC only supports Mcode that do system functions such as turn on this or 
> turn off that.
>
>   
Hi

i believe  there is no way at the moment to include Gcode in a coustom 
Mcode function as its just a shell script for running commands (turn a 
pin on off etc)

you may be able to write the probing function as a "sub" program/file 
and call it with parameters etc
i was thinking about coding some probing cycles for bore sizing, hole 
PCDs etc for use with renishaw probe
so if you wish to donate the basics feel free
depends what you wish to do with the returned results also

robert

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] G76 Threading

[Kirk Wallace]

On Tue, 2009-09-29 at 17:04 +0100, Andy Pugh wrote:
... snip
> 
> > http://www.youtube.com/watch?v=NDA48nLdbiI
> 
> More data after a long discussion on the IRC channel:
> HAL setup: http://www.pastebin.ca/1581821
> Halscope grabs:
> http://www.atp.pwp.blueyonder.co.uk/G76.png
> http://www.atp.pwp.blueyonder.co.uk/g76b.png
> 
> It seems to be related to the index pulse rate. But there is no trace
> of the index pulse in the input to motion.spindle-revs
> 
> --
> atp

I have only read the original post and watched the video, so I may be
off base here. I had the same symptoms on my lathe. I believe the thread
pitch and spindle RPM are at a rate that is beyond the Z axis abilities
to accelerate. I slowed my spindle RPM down and allowed for a fair
amount of air cutting to allow Z to stabilize before reaching the real
threading. I also tried to optimize my acceleration settings. Too high
of an acceleration number created following errors, so it's a
compromise. Basically your Z cannot instantly accelerate to match the
spindle RPM. It's like trying to grab onto a moving carousel. It just
came to mind, I wonder if changing the spindle RPM would help -- slow at
first, fast in the middle or the tread, then slow again at the end?
-- 
Kirk Wallace
http://www.wallacecompany.com/machine_shop/
http://www.wallacecompany.com/E45/index.html
California, USA


--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Encoders

[Dave Caroline]

you need a good contrast with reflective, I prefer a gap type, ambient
light is another problem to watch for

Dave Caroline

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Encoders

[Andy Pugh]

2009/9/29 Dave Caroline :
>
> do you need one of use to make/cut a disk

My machine has a milling head and a 4th axis, so making my own is
fairly straightforward (But thanks for the offer).
However I run the risk of doing a lot of machining and still having
exactly the same problems if it turns out that the paper encoder is
adequate and that the problem is elsewhere, or if I choose my encoder
resolution unwisely.

The simplest solution would be to machine a series of slots in the
lathe spindle drive pulley face, I think. (my encoder uses reflective
sensors, I just need to check that there is enough contrast between
cast-iron and no cast-iron.

My system seems to track a 50-line encoder adequately, would that
nromally be considered enough resolution for threading?

-- 
atp

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Encoders

[Dave Caroline]

do you need one of use to make/cut a disk

Dave Caroline (archivist)

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] Encoders

[Andy Pugh]

(Sorry to start yet another thread on much the same subject, but this
is a bit broader-ranging)

It seems that spindle-synchronised motion is very sensitive to encoder
regularity.

Using the p-port to read the encoder position means that as the
encoder linecount goes up, quantisation error in the measured
positions also goes up, and so the inter-line period noise increases.
Does this mean then, that very low linecounts will give less dither,
and better results?
http://www.pastebin.ca/1583502
Is the raw halscope data from my machine. If you plot the encoder
position it looks dead straight, but the raw data shows that the
difference between successive samples is quite variable.

Is this possibly the reason that my attempts at threading are so hopeless?

I would be the first to admit that my encoder is rubbish, it is a bit
of computer-printed paper wrapped round the lathe spindle, but even if
I was to get a high-accuracy encoder disc I feel I would still be at
the mercy of sample quantisation errors.

Any opinions on the best way forwards? I have got to the position
where I want to start the project that I started building the lathe
for, about a year ago. I don't really want to pull it all apart to
change to an FPGA board if that is avoidable.

-- 
atp

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] Fwd: Feature Request.

[Andy Pugh]

I understand  that some interpreters write the current z,y,z etc values to
memory registers (I believe Fanuc uses #5041-#5046)
Would it be possible to add that to EMC2? at the end of each move
would be often enough.
It would be handy for "adaptive" G-gode modules so that you could jog
to a start position and say "machine from here to X = 20 in .2 steps"
I have managed to do it with G28.1 then reading from #5161, #5162,
#5163, but as that stores absolute position I then have to
back-calculate relative position from the G54 parameters (#5221,
#5222, #5223) and the G92 offsets (#5211, #5212, #5213)  and if there
is any tool length offset set then all bets are off...

Actually, if G28.1 could "accidentally" store the relative positions
as well as the absolute positons somewhere (for example in #5041
onwards, that would be great.

-- 
atp

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] Spindle Coordinated Motion

[Andy Pugh]

As it seems that nobody has any ideas about my thread-cutting issues
(and making a higher-resolution encoder with a smaller index pulse
didn't help at all) I have now decided I need to know how G76 and G33
work, ie what the control algorithm is. Is there a writeup anywhere,
or do I need to look at the source code? (which I imagine might well
be beyond my meagre skills). Could anyone give me a clue which modules
handle G33/G76 moves?

(Note that this message was originally sent from a non-subscribed
address, as were many others, and so the lack of replies is possibly
explained that way)

-- 
atp

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] G76 Threading

[Andy Pugh]

2009/9/27 Andy Pugh :
> 2009/9/27 Andy Pugh :
>
>> http://www.youtube.com/watch?v=NDA48nLdbiI

More information.
G33 is exactly the same.
Smaller pitches are better, but even 1.25mm pitch (20 tpi)
occasionally gets the wobbles.

--
atp



-- 
atp

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] G76 Threading

[Andy Pugh]

(I thought you were all ignoring my questions, but I suspect that I
was sending from an email address not registered with the listserver.
Brace yourselves for a flurry of posts)

I seem to be having a spot of bother with G76. I thought it was
working fine, then noticed that the z axis was running at max-speed
and cutting the wrong pitch. Slowing down the spindle and increasing
the z-axis accel limit produced the issue shown here:
http://www.youtube.com/watch?v=NDA48nLdbiI
It seems almost like a badly tuned PID controller.
It isn't a brilliant encoder, as can be seen on the velocity trace
(but note that velocity baseline is at the bottom of the screen), but
surely the position counts should update steadily enough?
Which encoder position is meant to be wired to the motion.spindle-revs
input, by the way? Stepconf uses encoder.0.position, but that seems to
be an integer, and I am wondering if it should be
encoder.position-interpolated. Watching the machine it is almost like
it is updating the carriage position once per rev...

--
atp



-- 
atp

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] G76 Threading

[Andy Pugh]

-- Forwarded message --
From: Andy Pugh 
Date: 2009/9/27
Subject: Re: G76 Threading
To: "Enhanced Machine Controller (EMC)" 


2009/9/27 Andy Pugh :

> http://www.youtube.com/watch?v=NDA48nLdbiI

More data after a long discussion on the IRC channel:
HAL setup: http://www.pastebin.ca/1581821
Halscope grabs:
http://www.atp.pwp.blueyonder.co.uk/G76.png
http://www.atp.pwp.blueyonder.co.uk/g76b.png

It seems to be related to the index pulse rate. But there is no trace
of the index pulse in the input to motion.spindle-revs

--
atp



-- 
atp

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] Mcode scripting ??

[VMAXEmbarq]

I see where EMC2 supports User Mcodes. What scripting language is used to do 
so?

Can you include Gcode moves in the Mcode as well.

I have Mcodes from another system that do things like probing solutions. 
These functions are called as Mcodes and can be run from the Gcode side and 
from the MDI side.

Does EMC support this type of function ? From the user manual it seems that 
EMC only supports Mcode that do system functions such as turn on this or 
turn off that.

Thanks (;-) TP 



--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] srm?

[Jon Elson]

a...@conceptmachinery.com wrote:
> I try with ~ and without and still No such directory
> I used rm  and still No such directory
> I just type this into Terminals. Is this way to do that?
>   
When filenames have strange characters in them, like spaces, commas, and 
punctuation
symbols that mean something to the shell, you can enclose the file name 
in quotes.
So :

rm "/home/blat/bloop 123 456.dat~"

Jon



--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Hardware latency detector

[Michael Buesch]

On Tuesday 29 September 2009 16:35:26 Michael Buesch wrote:
> Hi,
> 
> I think the following new tool might be useful for some people here.
> It's a tool to measure hardware latency. That's latency _not_ caused by linux,
> but by the BIOS or something else.
> So if you observe latencies beyond acceptable limits with this detector, you
> can pretty much go and buy new hardware instead of wasting your time in trying
> to tune linux.
> 
> I didn't test it by myself, yet, but I think it can be useful nevertheless:
> 
> http://marc.info/?l=linux-kernel&m=124469647405168&q=raw
> 
> Documentation is included in the patch.
> 

Oh, I forgot to say, it should _not_ be used on an rtai kernel.
So boot a standard kernel with the patch applied to measure your hardware 
latencies.

If you use this on an rtai kernel, the rtai supervisor will interfere with the 
results.

-- 
Greetings, Michael.

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] Hardware latency detector

[Michael Buesch]

Hi,

I think the following new tool might be useful for some people here.
It's a tool to measure hardware latency. That's latency _not_ caused by linux,
but by the BIOS or something else.
So if you observe latencies beyond acceptable limits with this detector, you
can pretty much go and buy new hardware instead of wasting your time in trying
to tune linux.

I didn't test it by myself, yet, but I think it can be useful nevertheless:

http://marc.info/?l=linux-kernel&m=124469647405168&q=raw

Documentation is included in the patch.

-- 
Greetings, Michael.

--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] Rotation center

[5150]

Hi,
is it possible, in a 4 axes machine, modify the rotation center of the 4th 
axis? In other words, how can I say to the system which is the geometry?

Thank you
Luigi


--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Error in debounce documentation

[John Thornton]

Thanks for reporting this. The manuals have been corrected.

You have to loose the quotes as well like this:

loadrt debounce cfg=1,2,3

John

On 28 Sep 2009 at 12:42, Eric H. Johnson wrote:

> HI all,
> 
> This was from Andy's inquiry of a couple days ago. It appears that
> the
> documentation for the debounce component in the "Integrator Manual"
> (Page
> 94) has a slight error or typo. The syntax as written does not work
> for me,
> i.e.:
> halcmd loadrt debounce "1 4 2"
> but
> halcmd loadrt debounce "1,4,2"
> does.
> 
> It seems comma separators between values are required, at least when
> done
> from a hal file. If the commas are omitted, only the first group is
> created.
> 
> Regards,
> Eric
> 
> 
> 
> 
> --
> Come build with us! The BlackBerry® Developer Conference in SF,
> CA
> is the only developer event you need to attend this year. Jumpstart
> your
> developing skills, take BlackBerry mobile applications to market and
> stay 
> ahead of the curve. Join us from November 9-12, 2009. Register
> now!
> http://p.sf.net/sfu/devconf
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users



--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] srm?

[Mark Wendt (Contractor)]

Have you tried "ls /home/aram/Desktop/TR2~" to see if the directory 
actually exists?

Mark

At 01:03 AM 9/29/2009, you wrote:
>I try with ~ and without and still No such directory
>I used rm  and still No such directory
>I just type this into Terminals. Is this way to do that?
>thanks
>aram
>
>
> > On Mon, 2009-09-28 at 22:18 -0600, a...@conceptmachinery.com wrote:
> >> hi
> >> will srm myfile.txt delete file?
> >>
> >> i have this file, and directory is right.
> >>
> >> a...@aram-desktop:~$ srm /home/aram/Desktop/TR2~
> >> Error: File /home/aram/Desktop/TR2~ - No such file or directory
> >> a...@aram-desktop:~$
> >>
> >> how i can use srm command?
> >>
> >> thanks
> >> aram
> >
> > My guess is, the ~ my not be a valid character on the command line,
> > since the command line may interpret it to mean "home directory". For
> > instance, if my home directory is /home/kwallace, I could use "rm
> > ~/myfile.txt" the same as "rm /home/kwallace/myfile.txt".
> > --
> > Kirk Wallace
> > http://www.wallacecompany.com/machine_shop/
> > http://www.wallacecompany.com/E45/index.html
> > California, USA
> >
> >
> > 
> --
> > Come build with us! The BlackBerry® Developer Conference in SF, CA
> > is the only developer event you need to attend this year. Jumpstart your
> > developing skills, take BlackBerry mobile applications to market and stay
> > ahead of the curve. Join us from November 9-12, 2009. Register
> > now!
> > http://p.sf.net/sfu/devconf
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
> >
>
>
>
>--
>Come build with us! The BlackBerry® Developer Conference in SF, CA
>is the only developer event you need to attend this year. Jumpstart your
>developing skills, take BlackBerry mobile applications to market and stay
>ahead of the curve. Join us from November 9-12, 2009. Register now!
>http://p.sf.net/sfu/devconf
>___
>Emc-users mailing list
>Emc-users@lists.sourceforge.net
>https://lists.sourceforge.net/lists/listinfo/emc-users


--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Engrave.py cuts deeper and deeper

[Sven Wesley]

2009/9/29 cogoman 

> I am catching up on my EMAIL, and I've still got 10 EMC digests to read,
> but I wanted to comment on the quote below.  This gives the impression that
> you are setting the PID values for the servo motor on the bench with nothing
> attached.  This is not a good idea since these settings SHOULD be sluggish
> in the system.
>
>
They are tuned mounted on the machine. :)
--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Engrave.py cuts deeper and deeper

[Sven Wesley]

2009/9/29 Jon Elson 

> Sven Wesley wrote:
> > I can cannot see any changes in speed even if I push put all my body
> weight
> > on the Z-axis, it just runs super easy and the motors never gets warm. It
> > doesn't _seem_ to be a force/power problem.
> > I have put so much money and time in building a servo system. It's REALLY
> > annoying if I have to go back to steppers. To me, these eBay-items looks
> > pretty small too. Are they really going to make it?
> >
> I am now CONVINCED that your problem is a step timing issue, possibly a
> step-vs-direction
> setup time issue.  I am also sure the Rutex has some kind of a fault
> output, but you may not be using it.
> I remember the fault window is programmable, as opposed to Gecko's fixed
> limit.
>
> If you were to put stepper motors and a stepper drive on the machine,
> you might well have
> the exact same problem - many people have.  The timing of the
> step/direction pulses MUST
> meet what the manufacturer needs.  If the manufacturer's specs are
> non-existant or just wrong,
> that makes fixing this much harder.
>
> The basic problem is either the drive fails to detect some of the step
> pulses, often just after a direction change,
> or counts a step pulse in the wrong direction.  Gecko once had a problem
> with the pulse multiplier in their
> Gecko 210 (stepper) and 340 (servo) where if the direction changed while
> the multiplier was still putting out
> multiplied pulses, those steps would go in the wrong direction.  It led
> to errors in fractions of the commanded
> steps.  The fix was to either remove the pulse multiplier or make sure
> the software didn't generate a step pulse
> for some specific time after a direction change.  That's just one
> possible way such a problem could happen.
>
> Unless somebody knows the specific settings for your drives, you may
> need to systematically explore the
> range of settings and motion to see if you can identify which adjustment
> affects the problem.  And, if you find a setting that
> makes it WORSE, that may be an important clue to what the underlying
> problem is.
>
> You can make a chain of short moves in the same direction, with a pause
> between each move, and see if there
> is no error.  Then, make moves back and forth, with delay between each
> move - again, check for error.
> Then, move back and forth with NO delay between moves.  Does this make
> the error worse?  If you see it is
> worse with back and forth moves with no delay than either of the other
> movements, that is a BIG clue it
> has something to do with step timing vs the direction signal.
>
> Jon
>
>
The only thing I've got about the settings is "you should be safe with 2us
in step" and in the same reply the I got to learn that the direction
settings were unknown but low values are known to work. I've tried step
time/space between 1500 and 15 000 and direction hold/setup to as high
values as 200 000 but it doesn't make any difference.

I can try to run the machine in the same direction stepwise (instead of
changing direction), lets say 10 mm steps, to see if there's any difference.

Gene, I have tried to run a test program with 10 % feed and it looses
position anyway. If the amount of lost position is the same I didn't check.
I can do that as well.

A guy is going to send me a couple of other drivers and a another servo.
Then I can change one at a time to see what happens. Right know these are
the suggestions were it can be wrong:
1. Bad signal. Two different computers have been tested with the same result
though.
2. Wrong setup in step timing. Much likely, I'm not the only one who
experienced tuning problems with these.
3. Encoder problem. Not really tested. Only changed to the same type of
encoder.
4. Small servo's. Well, they may be small and think I'll change them, but
there are lost steps even at low feeds.
5. The drivers have an error. Have no idea, I don't get the feedback. New
drivers are on the way to test.
6. Servo/Driver combination doesn't work. Maybe, as I wrote, new stuff on
the way.
--
Come build with us! The BlackBerry® Developer Conference in SF, CA
is the only developer event you need to attend this year. Jumpstart your
developing skills, take BlackBerry mobile applications to market and stay 
ahead of the curve. Join us from November 9-12, 2009. Register now!
http://p.sf.net/sfu/devconf
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users