If you round your numbers in the cad system to the safe side (Make the arc bigger by where you place the arc center) I can be sure that I cut all the parts right.. I can not change Mach3 to round because the guys running micro machines will have trouble. You need to fix it on your side and I need to run many types of machines.

The following comp code is a simple square with 1 inch sides and .5 arc corners. If you look at the I and J words of the four corner arcs you will see they are all exactly .5000 or .0000 so there has been no rounding on the CAM side. These are the exact coordinates in the precise location and yet the new comp code will not work with it. If I change the G42 P.5000 line to G42 P.499999999999 it works fine. That would indicate the error is on the Mach side and not with the CAM as there would be no rounding I could do on the CAM side to fix this.

Using the R-word in place of an I and J is not really an option as it has its own problems with ambiguity of arcs greater than 180 degrees.

G00 Z.3

G00 X0 Y0

G00 X1.5000 Y-.2500

G42 P.5000

G00 Z.1000

G01 Z-.1000 F10

G01 X.7500 Y-.2500 F20

G02 X.0000 Y.5000 I.0000 J.7500

G01 X.0000 Y1.0000

G02 X.5000 Y1.5000 I.5000 J.0000

G01 X1.5000 Y1.5000

G02 X2.0000 Y1.0000 I.0000 J-.5000

G01 X2.0000 Y.0000

G02 X1.5000 Y-.5000 I-.5000 J.0000

G01 X.5000 Y-.5000

G02 X.0000 Y.0000 I.0000 J.5000

G01 X.0000 Y.5000

G02 X.7500 Y1.2500 I.7500 J.0000

G40 (cancel cutter radius comp)

G01 X1.5000 Y1.2500

G00 Z.3

Graham