I have an idea that I will shoot past you here in a bit after I have taken a better look at the file.
Also wanted to know if the part is vibrating when it is being cut.
I hope not. The sheet is held down by a half dozen screws spread around it. I’m not sure I could secure it any more. When the issue occurs the entire table vibrates like a mad thing.
From the look of the inner part held by the tab when I get it out I’d also be surprised if it was vibrating. I can see the arc segments in the mirror finish which honestly I’ve never been able to see before because usually my cuts are not that clean.
Found an area on the profile spiral that is cutting below the o surface
!
I’m running it through CAMotics and can’t see anywhere its dropping below Z0. I also searched the gcode file and couldn’t find any Z-. Is this some consequence of the spiral arcs?
Here is a better plan for you. Leave everything as it is and add a lead out spiral also enter a lead move feed rate of 300 mm not the 500 mm full speed that you have it set at and see if that helps.
Don’t change the steps per
Ok, I made those changes but in the sim it didn’t alter the part of the cut at issue at all. Since the tabs don’t currently generate a lead in/out. So the gcode around the issue point is still the same. In order for there to be any difference around the tabs I had to enable lead in on tab generation and set a lead in spiral angle but that resulted in a full lead in from retract height which almost triples the run time of the cut to an hour.
I may try Steves suggestion of making a larger first pass around the cut tomorrow to make a larger channel, if it is the bit chattering against the walls and causing it to dig in to the bed somehow then that should alleviate it. I’m just real concerned that its more likely the inner part vibrating somehow. I guess I can pocket the whole thing, but it doesn’t bode well for being able to cut out the whole part of I can’t hold down this one well enough.