Let's see if this'll work - 22 April 2017
I've wanted a rail bike ever since I saw one in Bicycling magazine back in the late 1980's. And now - I've finally jumped in and actually started making one.
So far I've 3D printed a bunch of joints to connect rollers and some aluminium tubing for the outrigger - but they keep breaking as soon as I set it up on actual rails. Currently I'm printing the joints in brittle PLA which is the only material my printer will handle. I expect I'll have to try ABS or nylon to get something less brittle. PLA is fine for the prototyping stage though.
The outrigger roller is 3D printed in PLA and the front roller is the spool from a roll of 3D filament - which happens to be the exact width of rails in New Zealand (66mm).
My bits are clamped to the frame using mounting brackets from Freeload racks.
I'll post more once I get something that doesn't fall apart before I even sit on the bike.
This might actually work work - 24 April 2017