RE: Lead screw error compensation

>David wrote:
>In the old jig borers, I think the Pratt and Whitney was this way,
>the table nuts were on a lever arm, and the end of the lever
>followed a linear cam that was specifically designed to compensate
>for the error in that particular acme screw. That way the dials
>always had the correct reading for the table position. No reason
>that I can think of that this couldn't be done in software.
>David M. Munro

David,

It IS commonly done in software, and as both Jon Elson and Tim
Goldstein have pointed out, is in the LATEST EMC release so you can
even see HOW it is done by looking at the source code.

BTW, you machinists who are not programmers CAN still get SOME idea
of how this EMC thing works from this SOURCE CODE. It is pretty well
described (well-documented) by the Authors, so don't be afraid to
venture there. Like driving a car, you don't have to build engines to
drive, but it's a good idea to know how to fix a flat and change the
oil.

Ballendo