Hi all,

I am considering making a CNC plasma cutter frame and gantry using precision square tubing that bearings can ride along.

Does anyone have a good source for these? McMaster-Carr sells square tubing but I am not sure what to call "precision" square tubing withoutside surfaces sufficient for bearings to run along.

Also, what do you call the bearings that some people use in this application? It looks like they have an eccentric shaft hole that allows the bearing to be adjusted and then locked down. What are these called? Eccentric bearings? What kind of bearing?

Thanks,

Steve