We recently changed the configuration of our machine (added another motor to the y-axis etc...) and tuned the machine, and just finished our first test cut.

I have programmed in some 1 1/8" circles that cut perfect (those small circles are dead on), but they are part of a larger piece that was programmed to cut out at 40", and it is almost a whole inch off (just under 41"). We can tune it to be exact on the larger items, but when we do that, the smaller items (like those holes) cut incorrectly (they actually cut as slight ovals, with the y-axis correct, but the x-axis off).

It doesn't make sense to me that it would be precise for one but not the other. I found an old thread that someone else started with the same problem (http://www.cnczone.com/forums/showthread.php?t=32297) but there were no replys to it (I revived it with my reply, but it is in a sub category, and I wanted to bring it to the attention of the main category in case some of your experienced guys don't ever visit the sub forums).

Any help would be very appreciated, this is a very frustrating problem that just doesn't make any sense to me.