MecSoft Corporation

I am pretty new to CNC milling and was having a blast with it until recently.

I started using VisualCAM-Mill for Solidworks and was successfully able to create a 4-axis cut file for my Tormach PCNC 1100, load the GCode and execute. However now that I'm trying to get my first real 3-axis part setup I'm having some strange problems with the GCode. When loaded onto the Mill it gives me many errors, saying the arc segment has different starting and ending radius and may be distorted. The toolpath either does not show up on the mill's toolpath visualizer or it is completely screwy (rings that should be concentric are not, path is very jagged and non-continuous randomly).

I am using the PCNC post. I can't tell if this is a result of my settings in the CAM software, something with the PCNC post in the software, or a machine problem. I have not had any problems until now but haven't loaded much besides really simple stuff onto the mill, and this part is slightly more complicated (but still not very complex). The toolpath in the CAM software looks fine and I have triple checked all the inputs/settings.

Any ideas on where to start debugging this issue would be appreciated. Thanks.

From your problem description it looks like an arc output issue. The arc center for PCNC post processor in VisualCAM-MILL is set to absolute arc centers. Your machine is probably expecting incremental arc centers. Edit your post processor by selecting Post under Program tab and then click Edit from the set post options dialog. Select Yes when prompted by the edit file dialog. Click the Circle section from the left panel and over on the right panel, under arc center select Vector from Center to Start. Now save the post processor and close the post processor generator.

Note: If you are using the Mach3 control software with your Tormach CNC, you could use Tormach-Inch or Tormach-MM post process. If the controller is Path Pilot you could select Tormach-PathPilot-Inch or Tormach-PathPilot-MM from the post processor list. The arc centers are set to incremental for the above Tormach posts.