Re: [CAD_CAM_EDM_DRO] Servo-to-go vs Rutex r991h

jerrybiehler wrote:

>The mill I am looking at buying has standard brushed servos with shaft
>encoders. There is something wrong with the Hydropath III controller
>where when you ramp up table speed the spindle shuts down. I am just
>thinking of retrofitting.
>
>Now the question. The servo drives were just reconditioned by the
>manufacturer so I dont see any need to replace them. The two option I
>seem to have found are using the servo-to-go card at $888 for 8 axis
>or the Rutex r991h step/dir to analog interfaces. The STG card seems
>good in that there is direct feedback to the computer but it seems
>that it only supports EMC which I have found to be a setup
>nightmare.Are there any XP cam software that supports STG?
>
>

Have you tried the BDI 4.30 CD of EMC? Although I am pretty experienced
with this program, I used to run into a lot of difficulties, too. The
BDI 4.30
was the first one that did EVERYTHING automatically. I took the default
on every question, and it came up perfectly in less than 20 minutes.

I know of NO windows-based program that supports true servo operation
including the PC in the servo loop.

If you want to keep the servo amps, I have a cheaper interface that can be
connected to most newer computers through the parallel port. (The STG is
ISA only, which you won't find on most newer computers.) See
http://jelinux.pico-systems.com/PPMC.html for more info on it.

>The rutex drives will just give me step/dir inputs which everything
>supports, and at ~$90 an axis, a bit cheaper.
>
>It seems that closed loop to the computer would me more accurate. What
>do you guys think? Or should I try to fix the Hydrapath?
>
>

It's not exactly more ACCURATE, but velocity servo amplifiers with
tachometers
on the motors can be much SMOOTHER at low speeds. It MAY be more
accurate, and with the computer in the know, you can check the following
error
from time to time to make sure it is following the commanded position as
closely
as you need.

Jon