Machine Offsets

[dee26]

Hi, Been having this problem for sometime now. When in the middle of routing the machine will offset itself mainly to the left on X Axis by about 15mm or sometimes more. As you can imagine i have to scrap the material when this happens. Machine is a elu cnc 860 using artcam pro 8. Does not happen all the time but mainly with larger files. Any ideas why this would happen. hardware or software fault?.

thanks for any input.

Doing a little reading online and i think this problem appears to be whats called hard / Soft Overtravel. Can anyone enlighten me on this?.