Topics

1

General Mach Discussion / toolpath occasionally, randomly goes in strange directions

« on: March 16, 2010, 11:51:37 PM »

This problem used to be rare, but now it's quite frequent.  On my Sherline CNC (model 5200) machine running Mach3, the bit will be going along nicely, cutting a jewelry piece correctly, then, randomly, the tool goes way off path.  The X axis will overrun a few centimeters, then the tool will start going only in the Y direction for a centimeter, then it will head back on X in the other direction, all in the area of the wax it's not supposed to be touching.  I broke a bit recently because the bit was deep in the wax when the machine decided to go off path.  And it seems to go off path in the same way every time (though to different dimensions).  What made me finally brake down and post is that my tool ran into my four jaw chuck and kept trying to cut into it, causing lots of smoke and noise before I could hit stop.  I am not positive, but I believe my computer monitor wasn't reporting any problems.  As far as the computer was concerned, it was still cutting correctly and advancing along the G Code correctly.  No strange G code.  I usually run only new files, but this has happened to a file that I have run before.

Has anyone seen this problem before?  MikDundee on this post: http://www.machsupport.com/forum/index.php/topic,10879.0.html
seemed to have a similar problem, but no one seemed to solve his problem.

Any other details you guys want to know?

Thank you for your help.