Bicycle Hub

The use of 3D printing in developing countries to replace broken or warn parts is greatly beneficial. The low cost printing can be difference between having a mode of transportation or walking. By printing bicycle parts the need to buy new parts will be eliminated. I have printed a bicycle hub using PLA as a prototype for a simple road bike hub. This model uses loose ball bearings which are not as ideal as sealed cartridge bearings when used with PLA. For future designs a sealed cartridge bearing should be used. The hub profile was modeled in FreeCad, rotated around the axle, then sliced with slicer and printed on a MOST-Delta Printer.

Bill of Materials

1. Hub Axle- $1.25
2. Hub Nut x2 $0.10
3. Bearing Set x2 $.25
4. PLA $1.50
   1. Front_hub_osat_my5777.scad
   2. Upload and link to all STLs

Tools needed

1. MOST Delta RepRap or similar RepRap 3-D printer
2. Drill bit for reaming spoke holes
3. Open ended wrench
4. Grease

Thingiverse link OBJ/stl/FreeCAD files

Skills and knowledge needed

1. 3D printing
2. Bicycle Maintence
3. Bicycle Wheel Building

Technical Specifications and Assembly Instructions

How To:

1. Print hub halves (approx. 1 hr per half at 70% infill)
2. Load greased ball bearings into bearing assembly
3. Secure Bearing Top
4. Thread Axle
5. Secure Lock nuts
6. Lace Wheel with correct spokes

• Assembly about 30 mins plus wheel construction time
• Total time around 2 hours

Common Problems and Solutions

1. Be sure to use grease on bearings and axle shaft to minimize early wear
2. Use grease to hold bearings in bearing cup

Cost savings

1. Estimate: $4.50 (with new parts) $1.50 with used parts
2. Commercial Equivalent $10.00
3. Savings of $5.50 or 55%

References

• <ref>Wheel Building: "Why Build Wheels?" Wheelbuilding. Sheldon Brown, n.d. Web. 04 Dec. 2014.<ref>