Re: My Logan Clunker & leadscrew compensation

Doug,Jon,Ballendo:

Thanks very much for your insights. The expertise displayed in the
group continues to amaze.

I think my Logan spent a good deal of its life making the same part,
perhaps using a toolpost grinder. The machine arrived at my doorstep
wearing a heavy coat of grinding dust. A dial indicator positioned on
the saddle and reading the top of the front v-way yielded some tap-
the-gage-I-don't-think-it's-working readings.

Not being an EMC programmer it's easy to think a software solution
would be "easy." It would seem possible to implement this type of
error correction as a piecewise linear transform of the output
coordinate system. Presumably this could be layered on pretty close
to the surface of the control program. Some coding guidance might be
provided by the methods used to implement the leadscrew correction in
EMC.

I hadn't thought of a cam-operated system based on the same principle
of operation as a taper attachment. That could be made to work.

Jon, any chance that you could post a picture to your website or the
cced archives of the setup you described ?

There's another mechanical problem associated with worn v-ways. If
the carriage is adjusted to be a nice sliding fit on the unworn
areas, it's sloppy on the worn spots etc. I can imagine a smart
electro-mechanical adjuster, but I don't immediately see a practical
solution to this problem.

Thanks again.

--Jack