Re: [CAD_CAM_EDM_DRO] Encoder counts/revolution

vavaroutsos wrote:

> This is probably a stupid question, but is there any reason to avoid
> an encoder count that is not a nice neat base ten number? For
> example, 2048 cpr vs 2000 cpr? With a 5 TPI ball screw and no
> reduction, the 2000 cpr encoder would give 0.0001" per count vs
> 0.000098" per count for the 2048 cpr encoder. I don't think this
> would really make a difference, but I would appreciate the opinion of
> some of you experts.

Assuming your resolution is high enough, any program that uses
floating point arithmetic (EMC, for instance) will handle this perfectly.
Some other progams that do all the arithmetic in fixed point may have
some odd errors that creep in at certain positions where the
roundoff accumulates just before it is corrected. I suspect that
an error in the .0001" range is not going to bother you unless you
are building a coordinate measuring machine.

You should check the documentation for the program you plan to
use, just to make sure this is not a problem. Some programs need
you to specify the steps/inch in integer units.

Jon