newby here,,,,hard time loading to usb...

bob vesneske shared this question 8 months ago
Need Answer

hello,,,i can get a drawing , clean it and fix it,,,,then do the output to fastnest,,,set it up,,then save it,,,it runs great in fastplot,,,,so I go to find it to load on a usb and cant find it or its not right format???

then I finally found one and I got an error once I loaded in machine------G41/G42 illegal(line:54)!

whats that??? and how do I fix it??

im near Chicago,,,is there any classes or training for the fastcam software???

Comments (1)


Hi Bob,

Thanks for getting touch. For the extension issue, you should check your SETUP.DAT file in your FastCAM Folder. Look for the "EXTENSION,XXX" line in file, and edit the extension to match what you need for your controller, E.g.

to get NC extensions, make it:


To get CNC extensions, make it:


Also you may find the FastCAM Information starter pack useful:

In particular the part closure guide here:

As for the G41/G42 errors, that is KERF compensation error on line 54 of your code. So your controller is unable to cope with the Kerf adjustment required by that line. Usually this is caused by a really tight movement, or an angled movement that Kerf Compensation cannot implement.

You can try and figure out exactly where this motion is, and try to flatten it out, or you can try and use the Kerf Compensation that is in FastCAM instead. Here is a guide on how to use that:

Finally, feel free to get in touch with our Chicago office:

Hope this helps!


Alex Fagan