Ken's Dual Barrel Affordable Rock Tumbler

This rock tumbler was inspired by J_T_3_D's Affordable Rock Tumbler, as well as other versions. But I designed this frame for a specific type / brand of geared motor.

The barrel wheel comes from a design by Spretrep:
https://www.thingiverse.com/thing:2967501/files

The involute gears were generated using an OpenSCAD script by Catarina:
https://www.thingiverse.com/thing:1339

Full description, instructions to be added soon.

Parts List:

• 3 threaded rods - 5/16" x 36" (all to be cut in half to make 6 - 18" rods)

• 52x 5/16" nuts

• 32x washers, around 1" outer diameter, inner diameter at least 5/16"

• The frame was designed to work specifically with the following type of electric motor. There are several variations of it that will work, 12v or 24v, and with different output gearings. The important thing is the 6cm square flange. I chose a 24v - 100RPM motor, at the time it cost $12 CDN. Honestly I think it was mis-priced, because its out of stock now, and all of the other variations cost between $50 and $70 CDN. Nonetheless it appears to be a good motor, it's working well, doesn't even get warm.
  https://www.amazon.ca/DC12V-Micro-Metal-Adjustable-100RPM/dp/B07CRL4JJW/ref=pd_nav_hcs_rp_1/146-7887078-5474761?_encoding=UTF8&pd_rd_i=B07CRL4JJW&pd_rd_r=333dfb8b-e7f8-4fb3-a7dc-633add97640a&pd_rd_w=MyPaG&pd_rd_wg=Oj7cO&pf_rd_p=790e78b4-0cfd-4dc4-9583-138b5f0ffce0&pf_rd_r=3KNJG0DGX6TRN6Q57CCE&psc=1&refRID=3KNJG0DGX6TRN6Q57CCE

• I chose to use this 24v / 3A / 72W adjustable power supply. Changing the voltage controls the speed of the motor. It's working fine, but be aware that most of the adjustment range is compressed into the last 10% of the dial.
  https://www.amazon.ca/gp/product/B08DKJ6JLY/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

• 4x skateboard bearings: 22x7 mm. The inner diameter must be 8mm or 5/16" to fit the threaded rods.
  https://www.amazon.ca/gp/product/B07DZDLB3N/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

• 16x o-rings for the wheels on the threaded rods. The size can be from 27 to 29mm. Maybe they're cheaper bought separately, but I chose to buy them in a kit:
  https://www.amazon.ca/gp/product/B06XCQQPXS/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1