with the Onefinity machine, for attaching the feet, you just get wood screws (packing list) but I would not use such screws. I would use bolts matching the corresponding diameter in the feet, possibly with a matching sleeve. This drawing from Bill @Machinist will help you:
This is from Onefinity:
Image: Left: Foreman model foot. Right: Journeyman, Woodworker and Machinist models feet.
Note that the footprint for a single foot is the same for all machines, even if Foreman machine has higher feet.
Sure. Good idea. That’s how I plan to do it. But I would not use MDF to build a table. It is too soft, too flexible, and of heavy weight at same time. Plywood is much stiffier. Also MDF is much more prone to swelling as plywood. As for highly moisture resistant (HMR) MDF, I have no experience, never saw a use case. I use MDF only for speaker cabinets, where you want no acoustic resonance. Or for a wasteboard, but I think I will try the HDPE wasteboard as discussed the other day. HDPE is 100% recyclable, simply by melting it. MDF is (by far) not.