DIY PDW Bindle Rack, Try 2

prusaprinters

See: http://www.thingiverse.com/thing:2069378 I never actually tested this. More for documentation purposes & if someone wants to pick up where I left off. I was trying to make a DIY PDW Bindle rack by cannibalizing the platform off some cheap rack & somehow fixing it to the bike. I thought I'd try & make an adapter to get a bolt perpendicular to all the other bolts to achieve this effect. I never tested this & or even tried to assemble it. I cannot recommend actually building this; it'll probably break, even if you print it with a favorable orientation. Assume a 20 lb load on the rack, & push it from the end (assume 20" length) - that's a lot of torque concentrated on this one piece. If you machine this from any metal, it'll be immeasurably better. Make me an extra one if you actually do this. I would trust a CNC'd aluminum version. How I Designed This http://www.trekbikes.com/us/en_US/equipment/cycling-accessories/bike-racks/bontrager-backrack/p/14631/ I cut off the legs on this rack, which I bought used for $2.50 since it was missing a stay. I lined up slots with the holes to tolerate some dimensional inaccuracy. I added drop-in nut features to hold the nuts against rotation when the bolts are tightened. Assembly & Materials ==================== x1 Bontrager BackRack, minus the legs x5 5 mm bolts x5 5 mm nuts x2 4 mm bolts + x2 4 mm nuts OR x1 4 mm bolt, extremely long + x2 4 mm nuts The 5 mm bolts/nuts affix the adapter to the rack. The 4 mm bolts/nuts affix the adapter to the bike. You will need seat stay eyelets (I wouldn't trust P-clamps). You might be able to get away with these: http://www.thingiverse.com/thing:1962052 http://www.thingiverse.com/thing:1961983 (probably this one) but, they'd be so much better if they were machined. A very long 4 mm bolt might be able to bridge the gap between the two seat stay eyelets, & this would be a lot stiffer. Chances are it won't work though, because you'd need something like a 4-5 inch long 4 mm bolt. Category: DIY