Duplicate Contours

This issue popped up today. I generated a fairly large job and noticed that the plasma was duplicating some contours. I looked at the code and sure enough, the code was there telling it to to that.

The odd part is that on the duplicate cuts, there was no torch off then torch on to start a new cut. On the first time around, it lead in, went around and when it got to the end of the cut instead of leading out and stopping, it just kept on going around again. On some contours it did it 2 times and on other it did it three times On the third pass, it lead out and stopped as it should, then went on to the next cut.

I checked for duplicate contours and also stacked duplicates. I did not find either. It doesn’t seem to be layer specific. I can have 10 or more contours on one layer and it might duplicate 2 of them.

Never had this issue before today. Any idea as to what could cause this?


That certainly sounds like overlapping contours in the drawing. Could you send me the drawing and job file so I can see exactly what is going on.

That was my first thought when I saw it happening. I’ve done that before, but in those cases, it duplicated the entire contour, leads and all. IE: It makes a cut leads out, stops, then repeats. This time it just traced the contour 2 or 3 times without stopping.

That said…I went into SheetCAM this morning and re-optimized in the nesting screen and the program seems to be fine now. I stepped it through in Mach3 and I don’t see any duplicates.

If it happens again, I’ll send you the job file before I try fixing it. If it’ll help, I can send you the tap file that contains the duplicates.

Overlapping contours can under some circumstances result in the cutter going around twice. If it happens again, please send me the drawing and job file.