Re: [CAD_CAM_EDM_DRO] Closed Loop PC Based CNC

You're sounding like you really want to complicate things! Remember
KISS - as much as possible anyway. I run my system closed loop with a
Galil motion control card. The motor encoders go back to the Galil card
and it computes the errors and outputs the +/- 10V signals for the servo
amps (analog amps made by AMC). The Windows front end and handwheel
(for jogging etc.) is by JRA see www.jraco.com I've been using their
system for production work for about 18 months and can highly recommend
it. JRA will sell you a Galil card or just the software if you already
have one.

Some additional thoughts: If a stepper system is set up correctly, then
you won't lose any steps - this applies to true stepper systems or Servo
based systems using Rutex or Gecko drives. It sounds like your steppers
are being pushed beyond their speed/torque limits - or you are getting
noise into the step & direction lines. If you go to a properly
specified servo system then you can still use open loop with good
results. I have a Flashcut system with Rutex drives that works great,
but I don't push it like my Galil/JRA based system. Jon Elson's system
using EMC is I believe, closed loop, based on his controller. Mach2
will only output step and direction signals so it is open loop but many
users are very happy with its performance and accuracy.

Good luck!

Cheers, Peter



nitewatchman5 wrote:

>
>I have a Bench Mill currently running with stepper motors in an open
>loop configuration. We are running production parts in fixtures and
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