Prettyinpurple

I have had this problem a few times now, never consistently though. I set my origin point on my cutter and then send my file. I test my file in preview to make sure there are no invisible cut lines (you only make THAT mistake once!) and then hit cut. Starts cutting as expected and then somewhere all the cuts seem to shift over. I have included photos as this is hard to explain. When the cutting head returns to the end it is NOT in the original starting position. Any ideas would be great, so far I am only cutting a 24" x 24" cut and I keep loosing up to 25% of my materials! Using SCAL3 Pro on a Mac Origin Point: End Point: Shifting: Missing nose: