Parametric roller bearing

thingiverse

Fully Parametric Roller Bearing A roller bearing that's fully parametric means its design is highly customizable and can be tailored to specific requirements. This type of bearing is not printed in place, where the parts are printed separately and assembled together. While print-in-place bearings make for a nice 3D printing demo, they must necessarily be rather loose to prevent fusing together. In contrast, an assembled roller bearing from individual parts can be made extremely tight, almost approaching a real bearing. Printing No support is required when printing the rollers. To avoid sticking issues, print them with a brim if necessary. Small bearings may experience this problem, but larger ones should not. Set the "seam position" to random to make the parts as round as possible. If you encounter an "elephant foot," where the first layer sticks out due to being squashed against the plate, trim it away from the roller ends and cage holes so they can roll freely inside the cage. Any obvious blobs should be trimmed away from the races and rollers before assembling. Assembling 1. Place the rollers side by side against the outer ring. 2. Fit the inner ring into the bearing, also against the outer ring. 3. Press the inner ring sideways into its place in the center of the outer ring. 4. Spread out the rollers evenly. 5. Insert the cage and snap the top onto the cage pillars. FreeCAD Model The main settings are provided in a spreadsheet. The model works down to 22mm diameter with an 8mm hole. However, the clearance needed for a perfect fit is highly dependent on the printer, so some experimentation may be necessary. For small bearings, consider using this alternative model instead: https://www.thingiverse.com/thing:3593568 8x32x8 Bearing An 8x32x8 bearing with 0.04mm clearance is included as STL files. Update 2019-04-26 The FreeCAD model has been tweaked to work down to 608 size, or 8x22x7. Update 2019-04-28 A problem that made the model unstable when resizing has been fixed, and the model now uses Freecad 0.18. Update 2020-04-14 One sketch in the Freecad model was overconstrained, which prevented the model from resizing correctly when changing parameters. This issue has been resolved by removing the unnecessary constraint.