I set this up with some 1" square tubing on the sides, some 1.5" for the main cross tube and some 1 1/8" tubing from a sacrificial Bridgestone frame for the stem mounts. Made the various bicycle fork and wheel mounts to fit some leftover stems I had, and all of it can go on any of the three positions I welded on the main tube. Finished with some rattlecan Duplicolor flat black and slid some inner tubes over the side tubes to help prevent sliding. I know, having a TIG welder and a lathe comes in handy sometimes.

I made mounts for two regular 9mm QR's and a 20mm thru axle for my Ellsworth.