My BB Filled LM8UU Type Bearings

thingiverse

These bearings accept 4.5 mm steel BBs. (Copper may work, but it has been heard that they can cause problems due to metal differences.) I printed these on a Printrbot Simple in PLA at .25 layer height and 10% Infill. (I have also tried printing them on a Makerbot Replicator 2 at Low Resolution with 10% infill, but they had a much lower tolerance. They turned out very tight and it took a long time to wear the BBs into their races before smooth travel was possible.) Dimensions: Short: 23 mm High, 22 mm Outer Diameter Long: 48 mm High, 22 mm Outer Diameter Inner holes are 8 mm in diameter. (This will work on 5/16” rods as well.) After printing you may want to use an Exacto knife or 8 mm drill to ensure the hole gives clearance for the rod since the plastic tends to swell into it a bit when printed. The Combined Version is the same size as the Short with the addition of parts to allow it to be used on a Prusa i3 Rework Y Bed. When assembling the combined version, place the BBs in the races, place the top and bottom on a flat surface, then use a clamp to press them together. (Attempting to twist them together may result in breaking the mounting brackets.) The Short uses 16 BBs. The Long uses 32 BBs. I really liked the concept of using BBs for bearings like http://www.thingiverse.com/thing:28905, but my attempts to print it out failed. I tried to use Netfabb Basic to repair the file, but still ended up with 739 flipped triangles. So I started designing this version instead. One thing I was hoping to do is be able to create a design that can allow me to modify in order to create odd sized linear bearings. Tearing apart inkjets and laser printers I found many rods are 5, 7 and 9 mm sizes which are not typical linear bearing sizes. I’ve included the original FreeCAD model files if you want to also modify the design to fit your needs.