Thumbler's Tumbler Model B Bearing Mod

This version of the bearing assembly makes no permanent modifications to the Thumbler's Tumbler Model B.

A stronger version that requires drilling through the tumbler's sheet metal is in the works.

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Print 4 of each part:

• Bearing_Bracket_Body
• Bearing_Bracket_Hanger

Settings:

I used ASA and standard Voron print settings: 4 walls, 40% infill (gyroid in my case), 5 top and bottom layers. I also used supports inside the SHCS recesses on the Bearing_Bracket_Body.

Using ASA, I scaled everything 101%, if you use a different material, you'll have to decide how to account for that material's shrinkage.

Other parts (BOM):

• 4x 608 ZZ Ball Bearings (8mm x 22mm x 7mm)
• 8x M3 heat set inserts (mine came from McMaster-Carr and the holes are sized for them - https://www.mcmaster.com/94180A321/)
• 8x M3x8 SHCS
• 4x 6x3mm Neodymium Magnets (optional)

Instructions:

1. Install a 608 bearing into each Bearing_Bracket_Body
2. Install the heat-set inserts into each Bearing_Bracket_Hanger
3. Install the 6x3 magnets into each Bearing_Bracket_Hanger (optional)
4. Attach the hangers to the bodies using the M3x8 SHCS in order to create 4 bearing assemblies
5. Remove the drive and idler shafts from the tumbler
6. Carefully remove the shaft retainer clips (4) from the drive and idler shafts - keep these as they will be reused in a following step
7. Remove the plastic bushings from the drive and idler shafts and clean the ends of the shafts
8. For each end of the drive and idler shafts:
   1. Slide a completed bearing assembly onto the shaft, so that the assembly is oriented with the SHCS facing away from the tumbler
   2. Carefully reinstall a shaft retainer clip onto the end of the shaft
9. Reinstall the drive and idler shafts back onto the tumbler