I stumbled on the C channel sections at the local scrap yard....an ideal place to find most things! Only a hundred bucks for the lot, it looks new and is well under half price, the 'metalo's' is a common source for materials. Maybe the big section is overkill on such a small machine, but I really want to avoid any flexing. I was going to weld the corners, but worried about twisting, so I may bolt the corners instead as I figure that with a hefty lump of thick plate to serve as a bed, nothing should move. Hi tensile 16mm samson rods were fairly cheap too....$90 for four with long nuts included. I plan to machine the ends down to a half inch and run 6201 bearings on each corner, mounted into the 8mm fixing plates. I figure it's best if I deal with one axis at a time, or it will seem too much computation. So far the machine's plans exist inside my head with nothing on paper
It's more fun that way.