I have a home built router running Mach 3. I use Fusion for G code generation. I cannot figure out why my cut outs are off by 1/16" . I did a test piece that should be 4" by 8". It came out 3 7/8" x 7 7/8". I have done a series of test drill holes to confirm accuracy of the router and they are dead on. I have regenerated the G code multiple times with various options. I checked the G code with a simulator and it measures out perfectly. I have looked in Mach 3 for tool offsets and can't find a problem. It's driving me crazy. Any help would be greatly appreciated.