Re: [CAD_CAM_EDM_DRO] Tool Comp G41,G42

stcnc2000 wrote:

>Hi to all, If you have to draw you part. It seems to me i would
>rather use the offset function that is built into Cad programs, like
>Intellicad or Autocad. If you want an example go to:
>http://STcnc.tripod.com/tutorial
>It shows you how easy it is to allow for cutter compensation.
>
>

But then, if an off-size cutter or tool deflection causes the part
to come out a bit out of tolerance, you have to go back to the CAD
and redraw the offset line, and redo the generate G-code function.

With cutter radius compensation, you edit the tool table to change the
apparent cutter diameter, and rerun the SAME program! A trick I use
for tricky, one-off parts, is to just generate the final (finish cut)
toolpath
using cutter radius comp and the toolpath eauals the part outline.

I put a spring-loaded ballpoint pen in the quill, and a sheet of paper on
a "platen" in the vise. I run the program with the tool table set to a
diameter of zero, and verify that the drawing looks like the part I want.
Then, I tell it the tool is, say, .020" larger than it really is. I run
the program
and it makes a rough cut over the part, leaving it oversize. Then, I change
the tool table again, setting the actual measured tool diameter, or
compensating
slightly for tool deflection, give it a number .002" smaller than the tool
measures. Run the sam program again, and you get the finished part.
By twiddling the size given in the tool table, you can adjust for tool
wear to keep the parts coming out within tolerance.

Jon