Printable PTFE linear bearings for 8mm rods and 4mm ptfe tubing.

thingiverse

I designed these new linear bearings specifically for when I assemble my steel Prusa. I didn't want to wait for IGUS bearings so I never bothered with those. The benefit of these bearings over the usual ball bearings is that they can be made at home, weigh a lot less than the usual aluminum bearing blocks, are quieter and can be readjusted many times as the PTFE liners wear. Insert three 4 mm diameter and less than 25 mm length pieces of PTFE tubing (six pieces of less than 15 mm length for the long bearings) into the inside of the bearing, slide it onto the shaft and insert an M4 grub screw or regular M4 screw in the single hole in the middle to adjust the tightness of the bearing. It will need to be adjusted after bedding in as well. Use four M4 screws to attach the bearings, just like the usual bearing blocks. PTFE-bearing02 has slots for regular M4 nuts (nyloc nuts are too hard to turn and will break the blocks unless they are threaded before installing). The mounting dimensions are the same. The bearings will bind if they are moved on the rod alone without mounting them to a rigid surface because they are easily teetered by hand. When two bearings are sliding together with a frame, they should glide smoothly. I might upload more variations that orient the PTFE liners differently later on for load optimizations in different applications. PTFE-bearing01 has integrated threads in the mounting holes. PTFE-bearing01-nut has hex slots for inserting M4 nuts for the mounting holes. PTFE-bearing02 has integrated threads in the mounting holes, and teflon linings rotated 90°. PTFE-bearing02-nut has hex slots for inserting M4 nuts for the mounting holes, and teflon linings rotated 90°. PTFE-bearing03 is externally shaped exactly like the normal bearing blocks, and has integrated threads. PTFE-bearing03-nut is externally shaped exactly like the normal bearing blocks, and has hex slots for inserting M4 nuts for the mounting holes. PTFE-bearing04 is long version, and has integrated threads in the mounting holes. PTFE-bearing04-nut is long version, and has hex slots for inserting M4 nuts for the mounting holes.