Y axis shifting while running a file

[philor@earthlink.net]

While running a file on the Shopbot the Y axis shifted. The cut was very light .032 deep with a sharp V-bit. The file ran fine until about half way through the file. The problem occured at the beginning of a new line of code. I started the file again and had the same problem but this time it occured earlier in the file.
This is not the first time this has happened. It has only happened on very light cuts. There were no sounds from the motors or gears to indicate that there was a mechanical problem. What's going on? I'm using the DOS version of SB-Cut on a benchtop Shopbot.

[jamesgilliam]

Phil, I have not had this happen to me "yet", but the first thing that comes to mind is what type of hold down are you using for your parts?

[philor@earthlink.net]

I called tech support for help, they were great. They helped me troubleshoot the problem. Turns out the Y-motor was the culprit. It was still under waranty and they had a new one in my hands by the end of the week.