Circle Error - Help!

We are having trouble cutting an accurate 2" circle. We suspect something in SheetCam. We are opening an accurate 2" circle dxf file, creating a tap file in SheetCam, loading it into Mach3 and our cuts are consistently as the attached pictures. We have calibrated and re-calibrated our machine and can cut a very accurate 2"x3" rectangle. Is anyone aware of any settings in sheetcam that may contribute to our dilemma or should we be looking elseware? It appears to be at the transition from positive motion to negative motion on the Y axis.


That is a mechanical problem on your machine. It looks like you have backlash in one axis.

Thanks Les… I am diagnosing the problem remotely from the machine (100 miles away). Backlash has been one of my suspicions. I’m very happy to rule out SheetCam. Thank you for the quick reply.