I'm looking to build a cnc router large enough to cut a single piece of plywood. Currently I'm trying to build a support table on the cheap. The size would probably be around 9' x 5'. Is plywood or MDF dimensionally stable enough to use as a base for this table? I've also been looking into framing systems and steel tubing. Any suggestions. Thanks
It depends on what you're trying to do with the table and potentially what tolerances you're trying to hold. However, if you seal it well or keep it in a temperature / humidity controlled room, it could be dimensionally stable enough. I used 2x4's for my table, but my router (built from 80/20) rests on top of it, so if the table moves a bit it's not the end of the world.