Compact Thomson Super 8 Ball Bushing Block (bearing block)

thingiverse

Update 11/09/14: An even better design is here: http://www.thingiverse.com/thing:534210 or here: http://www.thingiverse.com/thing:540629 They use screws to precisely adjust fitment- no more cable ties! For 1/2" guide rail, bearing is held in block with two tie-wraps, block has two holes for #6 screws on center line and spaced 26mm apart. The flat surface is 19.05 mm (3/4") from the center of the guide rail. Use small tie-wraps to provide fine adjustment of "fitment". Put the bearing on the guide rail, slide the block over it, then carefully cinch down the tie-wraps while checking the bearing motion. If there's any binding, you got too tight- cut off the tie-wrap and try again. Instructions Printed with ABS, 0.2 mm layers, no raft, no brim, no support material needed or used, 40% infill, 2 vertical and 2 horizontal shells. A single block prints in about 90 minutes. I printed 4 of them at a time and found some slumping in the thin curved part that covers the bearing, probably due to the amount of time spent on the hot build platform, so maybe print these two at a time or use PLA.