RE: [CAD_CAM_EDM_DRO] Deskncrt

DeskNCRT is a DOS port of the EMC code so my comments while based on EMC
should be appropriate for DeskNCRT. While it is running in open loop
mode the freqmod.o module (the one that smdromod.o is based upon) is
based upon the servo to go motion module. As such it is expecing to see
an encoder signal to generate the error count. To make it work for open
loop steppers they virtualized the encoder signal in software and you
configure it by setting it to the same value as the steps per inch. So,
the software commands 1 step and another part of the software then
generated one encoder count. Because it is using the rest of the servo
code the response is tuned just like on a servo with the PID values.

I have never done any more with DeskNCRT than load it, play with the
interface, decide I preferred EMC and move on. While I am not a CNC Pro
user I find it hard to believe it is not working for you as all the
feedback I have heard (much) is very positive. If you are open to trying
things I would suggest you get a copy of the EMC BDI and just use
freqmod instead of messing with a DOS port of it.

Tim
[Denver, CO]

> -----Original Message-----
>
>
> I bought Cncpro for the constant contouring feature. However I'm
> having trouble getting it to work properly. I had played with
> Deskncrt in the past and loved the smoothness, but couldn't keep it
> from overshooting the tool path. I'm running at 2000 steps per in.
> Max speed is 10 inchs a sec. Using servo's with encoder feedback to
> hardware (Gecko G320). If using Deskncrt in an open loop mode why
> would the PID need to be tuned. Can someone help with some basic info
> for setting up Deskncrt to get me started in the right direction?
>
> Thanks, Frank
>
>
> Addresses:
> FAQ: http://www.ktmarketing.com/faq.html
> FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/