I have been wanting to do this mod for a while now, finally got around to it. Mild steel dowel pins for shelving, 25mm, 2.98-2.99mm OD straight nice little axles.
They need to be sanded down to fit pulley bearings, like 2.95-2.97mm. I used a hand drill as such: chuck up the dowel, use a long narrow section of sand paper to wrap around it, press with fingers and hand ‘lathe’ the dowel to 2.95 or lower, moving back and forth on the pin to make it as even as possible. a little smaller (narrower) is fine versus tight is bad (wreck your cheap bearings). Good results were had using 220/400/600 grit in stages to achieve a nice shiny smooth surface. They seemed easy to get it close enough to flat to make the bearings happy. Remember to work the sand paper back and forth dont ever sit in one spot and let it make deep grooves.
Shown are 2 stages of development, some prototypes in use and a more developed version (clear ones) going on a new printer frame.
Taulman Tech-G has almost no shrink or swell. had to redo CAD to nearly exact dimensions between metal and plastic parts. Nice stuff, resonable price. Upgrading the first printers frame to all Tech-G.
