My other cnc (Lumenlabs based design0 using bushings is almost done now.
Taking the bushing idea farther I modeled another new design as a cross between the MPCNC and my Ultimaker clone printer.
I got a bunch of Mach3 boards in DHL somewhere, and a Aluminum foundry somewhere between China and my shop to experiment with new ideas, so figured I would re-visit this.
It is designed to accept both nema23 and nema17 motors without any re-design or re-print.
Brass bushing is 1 and 1/8 inch brass tubing that happens to be exactly 1 inch inside diameter. It is a tiny bit tight, so I used some 600 grit sandpaper to open up the bushing a little bit, then made a sort of adapter with a short section of the 1 inch pipe to mount to the drill with a m8 bolt. I then put polishing compound on the stainless tube and ran thru the center of the brass tubing bushings I cut 20mm long on the lathe.
I have not printed this pictured one yet. Still debating, carbon fiber or cast aluminum. I got a couple kilos of CF in the shop and the foundry soon to arrive. My CF filament prints so far have turned out very accurate dimensionally. Much better than my regular PLA. however the Alu is tempting me… lol