This is a model of a mechanism I have seen a couple of times. The mechanism also appears in the book "Five Hundred and Seven Mechanical Movements". In the book it is listed as #027 and called "Multiple Gearing".
The design was created in OpenSCAD. The OpenSCAD model is parameterized so that the number of arms on the small wheel can be changed easily. I have included SVG files for laser cutting models with 2,3,4,5 and 6 arms. the other parts are common between the designs.
There is a Youtube video that contains detailed assembly instructions:
https://www.youtube.com/watch?v=bFRtYIas8WU
What you will need:
For each arm on the small wheel you will need a 3D print of:
multiple_gearing_Print_3D_A.stl
You will need a single 3D print of the model:
multiple_gearing_Print_3D_B.stl
The number of fasteners and bearings required depends on the number of arms in the design. Here is a generic list of the fasteners and bearing sizes.
Parts:
Small Bearing: 683ZZ: 3mm x 7mm x 3mm Deep Groove Bearing
Big Bearing: 608ZZ 8mm x 22mm x 7 mm Deep Groove Ball Bearing
Rounded Head Screws for Sheet Metal, #6, 1/4" Long (McMaster Carr PArt Number: 90077A144)
Rounded Head Screws for Sheet Metal, #6, 3/8" Long (McMaster Carr PArt Number: 90077A146)
Flat Head Screws M3 x 0.5 mm, 16 mm Long (McMaster Carr Part Number: 91420A126)
Wood:
5.2mm - Sande Plywood (1/4 in. Category Common: 1/4 in. x 4 ft. x 8 ft.; Actual: 0.205 in. x 48 in. x 96 in.) (From Home Depot)
Tools:
10-24 tap
scorch
