I successfully found the weak point in the initial design
The foot snapped as soon as I put my weight on the bike, I likely underestimated the dynamic load of my weight jumping up / down on the crank to start out, was probably 400+ pounds of force. Will just need to cut out a replacement foot design with a more reasonable traingular design instead of a peg leg. There were no clearance issues that force the peg leg design, I just thought it looked interesting
First half of vertical supports being welded onto frame
Then using some 2x4 spacers I welded the vertical support onto some 1" flat bar that I drilled and mounted on the main rear axle. I went with a 3d printed abs part to connect the forward edge of the frame to the bike. All of the propulsive force and torque generated by the foot touching down behind the axle will be going through that 3d printed part
Welding the crankshaft pieces together on the frame worked well, I had just moved the welding clamp here and forgot to move it back before tacing the last piece, luckily I didn’t destory the ball bearings by sending the welding current through them.
Ended up not getting lucky on chain length and had to put in a fixed tensioner for now, I had this spare sprocket from when I was still figuring out the drivetrain
I was lucky in that everything cleared and there was no fundamental flaw in the frame or assembly process, I just had to switch from a cap head to button head screw and the tensioner retaining bolt cleared the strut here
One of the design goals was not physically altering the bike, so the mechanism can be unbolted from the bike easily after removing the chain