Repeatability Issue

[vw_chuck]

Sounds like there is a move in your gcode that is causing it to miss steps. I had a lead in too high once and it would miss some steps and move my X axis just like what you are seeing.

[cnckeith]

4mm screw pitch at 1:1 and the overall turns ratio should be set to 4 mm per turn or 6.35 turns per inch

4 mm screw pitch at 2:1 overall turns ratio should be set 2 mm per turn or 12.7 turns per inch

[DLAM]

I will get some pictures of the drive. The gear reduction is 2:1 between the servo and the Ball screws. I pretty much have 12.7 turns per inch. when I did the math for fine tuning of the axis I came up with a longer decimal.the belts are 20 mm wide and very fine pitch timing belt.

I am in the process of upgrading CNC12 to the latest version. I am having problems in the old wizard in getting screen shots of the 3 tabs under primary system. They are not available. the are listed but will no hyperlink and will not expand. I am trying to get the upgrade done so I can get back on to the axis problem.