previously the steering column was 0.5” tube, sealed ball bearings, and a 1.25” OD as a housing. I worried that the 0.5” tube, extended about 11” to the handlebar, could easily bend or break.
Using the same seats for the ball bearings are new plastic bushings made from acetyl copolymer. Not as slippery as ptfe, and not as soft as UHMW, it turned on the lathe quite easily. Now the steering tube in 0.75” OD.
one reason to fix and finish the handlebars was this realization: as soon as the pedals, chains and derailleurs are mounted we will want to ride a bit. So handle bars are done, and on to the brakes.
The above box is temporary, it converts each brake handle to two different brakes (remember this is a 4 wheel bicycle).