Re: [CAD_CAM_EDM_DRO] reducing the encoder line count

Scott Nelson wrote:

> I think I need to toss a little bit in on the P-W Tape-O-Matic. I am an
> engineering type out of the aerospace arena and we had lots of these around.
> I think the last ones I used were '62 models. They did indeed have the
> encoder on the opposite end of the shaft. It was under a simple cover and
> just a basic plastic wheel about 4" in diameter that ran between a reader
> head. The machines worked very well for what they were designed to do. That
> is the thing they were not mills but drilling machines. They positioned the
> table and waited until the operator cycled the quill then moved on.

Ahh, this is a totally different situation from a milling machine! This is what
is called a "positioning" drive, rather than an "interpolating" drive. The
servo bandwidth requirements are much less for a positioning drive, and
so the problem with oscillation is much less.

Jon