My BB Filled LM8UU Type Bearings

Prints (0)


These bearings take 4.5 mm steel BBs. (Copper might work, but I have heard that they may cause problems due to the metal differences.) I printed these on a Printrbot Simple in PLA at .25 layer height and 10% Infill. (I have also tried to print these on a Makerbot Replicator 2 at the Low Resolution with 10% infill, but they had a much lower tolerance. Ie, they turned out very tight and it took a long time to wear the BBs in to 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 should work on 5/16” rods as well.) After printing you may want to use an Exacto knife or 8 mm drill to make certain the hole will give clearance for the rod as 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 I suggest placing the BBs in the races, placing the top and bottom on a flat surface and then using 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 the bearings like in, but my attempts to print them out failed. I tried to use Netfabb Basic to repair the file, but still was ending up with 739 flipped triangles. So I began to design this version instead. One of the things I was hoping to do is be able to create a design that could allow me to modify in order to create odd sized linear bearings. Tearing apart inkjets and laser printers I have found many of the rods are 5, 7 and 9 mm sizes which are not typical linear bearing sizes. I’ve included the original FreeCAD model files in case you want to also modify the design to fit your needs.

Design Files

File Size

88.9 KB
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