Re: [CAD_CAM_EDM_DRO] Measuring accuracy

Gregory Kamysz wrote:

>I just found out that the accuracy of my setup won't be defined my the
>mill but by the software I'm using. I've looked at all of the sub-1k$
>software and they all seem to work the same. There is always some
>rounding in the numbers. Much more tolerance than accuracy in the mill
>would cause. If I write the G-code, it's not a concern but if I use a
>software to generate G-code I'll be lucky to get +/-.05mm before I even
>start the spindle.
>
>The error I'm talking about is when using a .25mm step over and my part
>edge falls somewhere in between a step. Sure, I can cut parts at .01mm
>stepover but who is going to wait weeks for a part to run on the mill?
>If I want something pretty to look at, it's not a concern, but if I want
>to use the part in an assembly, it's unreasonable.
>
>Am I missing something?
>
>

Sheesh! Any CAM system should have provisions for roughing and finishing
passes. I suppose some of them require you to define the roughing pass and
the finish pass separately, as you might use different diameter tools
for the
two passes. So, you'd define the roughing pass to cut almost to the actual
part outline, leaving just enough material for the finish pass to clean up.

Even Bobcad/CAM has pocket routines, etc. that can do the roughing passes
with a large stepover, leaving an amount smaller than the stepover for the
finish pass.

Jon