Re: [CAD_CAM_EDM_DRO] faster steppers

Hi Henrik,

What motor drivers are you using? I am wondering if this might be part of
the problem.

I don't have much load on the motor(s) at the moment as I only have one
slide finished and the other two motors are running in fresh air. The slide
I do have working is running on steel balls and so doesn't have much
friction. I don't think this is the problem as I get exactly the same
problem with any of the motors, as I crank the speed up they get to about
215/220 r.p.m. and then just stop turning and sit there buzzing and
dithering back and forth. I tried another motor this afternoon 3.6volts @
0.8amp - exactly the same result although it did get to about 230 r.p.m.
before it gave up.
My power supply for the motors is a fairly hefty 24 volt transformer feeding
a bridge rectifier and a big electrolytic capacitor, the driver boards have
a similar set up but using a 6 volt transformer and the rectified current is
put through a separate 7805 regulator on each axis board..

Ian
--
Ian W. Wright
Sheffield UK
www.iw63.freeserve.co.uk

----- Original Message -----
From: "Henrik Olsson" <henrik-olsson@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: 21 March 2001 16:47
Subject: Re: [CAD_CAM_EDM_DRO] faster steppers


> Ian,
> I'm using steppers w/ about the same data as you driven by my homebuilt
> drivers at 36V. Wíth the motors directdriving the ACME screw on my /
> PCB-drill (I can't really call it a mill) I can go as fast as Master5 can
> spit out pulses (8192 pps). Thats about 1200RPM. I have tried to measure
the
> maximum steprate with a function generator but I run out of travel before
> the motors stall.
>
> Note that I don't have much torque at that speed, my 'ways' are
ball-bearing
> drawer-slides and the table is light (8mm aluminium plate) so it moves
> pretty easy (NOT very rigid but enough for PCB's and plastics).
> You should be able to get more than 210 RPM. Maby your ways are to tight?
> What are you using as powersupply?
>
> /Henrik Olsson.
>
>
>
> Welcome to CAD_CAM_EDM_DRO@...,an unmoderated list for the
discussion of shop built systems, for CAD, CAM, EDM, and DRO.
>
> Addresses:
> Post message: CAD_CAM_EDM_DRO@yahoogroups.com
> Subscribe: CAD_CAM_EDM_DRO-subscribe@yahoogroups.com
> Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@yahoogroups.com
> List owner: CAD_CAM_EDM_DRO-owner@yahoogroups.com, wanliker@...
> Moderator: jmelson@... timg@... [Moderator]
> URL to this page: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO
> bill,
> List Manager
>
> FAQ: http://www.ktmarketing.com/faq.html
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>