Re: Anyone tried this stepper driver?

[Ray Henry <rehenry-at-up.net>]

Dean

I didn't see the half step.  That will help some with the kinds of resonance 
that cause step loss.  Drives that output signals like these are used all the 
time in countless devices but you will need to be certain that you limit the 
speed and torque demands enough to stay well within the capabilities of the 
mass/motor/driver/EMC pulsetrain.

I would run freqmod with it because of the smoother pulse train.  It will 
also help some to stay away from the very big granularities in freqmod at the 
top end of the possible frequencies.  Since most of the torque and step loss 
seems to come into play at higher pulse rates, I would think that the board 
would work well for small machines and motors.

Matt was running a Sherline at NAMES this year with direct drive on the 1/4 
20 screws.  This means that he was running INPUT_SCALE at 4000.  He wasn't 
pushing it at all but easily got 12 ipm .   That is about 800 rpm which is 
well below the speed where the torque of the motors he used falls off enough 
to cause any concern.  This board would easily run that machine.

If Joel Jacobs is listening a testamonial would help.  He developed his own 
half step unipolar drivers and ran my Grizz minimill a year ago at NAMES.  It 
looked and ran good as near as I could feel and see.   My indicator showed 
that it was not loosing any steps.

Now you get to suffer my personal opinion.  I am not affiliated with any of 
these companies.  I am a great believer in Gecko drives.  Before them I used 
Centent which Mariss from Gecko also designed.  These devices are rock solid, 
flexible, configurable, and handle much higher voltages and power.  But that 
does not prevent me from considering other drivers like these or the units 
that Steve Stallings showed at NAMES.  Let me put it this way.  If I had a 
spare $105.00 I'd get one just to see what it would do on the Grizz.  That 
really is a reasonable price for what it can do.  They would really lower the 
cost of getting motion on that roto-hexapod that I haven't finished yet.

Ray


On Saturday 18 May 2002 23:06, you wrote:
> It depends. You will get more torque with a bipolar drive (Gecko and
> many others). You also can/must (depending upon model) microstep with
> the Geckos(and others) which helps reduce/eliminate resonance.
>
> Tim
> [Denver, CO]
> Stepper drives, motors, and encoders
> http://www.KTMarketing.com/CNC.html
>
> > -----Original Message-----
>
> ---Snip---
>
> > Is that good enough for EMC?  Or should I be looking into GECO's?