[Lasershop]

Originally Posted by machintek Read the program and see what it is telling the machine to do. Did you check backlash in a dynamic state? What does that mean? I usually overcomp the backlash and cut a circle with a light spring cut. I can then sweep the circle with a dial indicator and measure the steps where the axis reverses direction. This is the amount an axis is overcomped and needs to be subtracted from the exaggerated value just used. It is a lot easier to measure a step than a flat (if zero comp was used). Use cutter comp and adjust the tool diameter so it comes out correct. That seems like the easy out. I have to do some linear milling tests to find out if the error is accumulative. Was it a G79 that is such a beautifully simple was to circular interpolate a hole? You could try that. I do all my mill programming within SurfCAM. I wouldnt know G code if it hit me in the head. Surprisingly though I wrote all of my software for my laser post about 7 or 8 years ago using Galil based programming and C++. Its a stand alone program. I can easily adjust the counts per inch with mine. Makes a difference depending on winter or summer. Some of the laser jobs I get I have to hit +- .0005. I was hoping I could find the count per inch variable within the SurfCAM or V2XT software just to play with it. You have many options. George

RonO