I have noticed that when I try to speed up a pocketing or profiling job, the machine consistently rounds the top right and bottom left corners of a rectangle. I have to slow it down to get a "square" cut. But no matter how fast I go, it always comes to the exact corner of the top left & bottom right corners. It doesn't seem to make a difference if I am setting the speed fast in the setup or push it faster with the % button. My speeds vary from 100-150 ipm on.25" endmill. Any thoughts?
Look up G-Code G64. If you have a G64 with nothing after in either the post processor header or your machine's setup file then your machine will try to keep up feed speed while sacrificing accuracy. If you add a P followed by a fraction the bit will slow down as it needs to keep close to the programmed coordinates (less the fraction). So: G64 says keep up speed even if it means rounding off corners. G64P0.001 says stay within .001 of the programmed coordinates.