Step 1: Make a rock tumbler out of some threaded rods, bearings, a motor, and a spaghetti jar:
Step 2: Get sand. If you don’t live in a beach/desert, you can probably get some for free from a landscaping supply place. (They charge per ton, so when you ask for a cup, they will think you are a crazy person and just give it to you.)
Step 3: Chuck the LEDs and sand into the thing and run it overnight.
That’s all.
Here’s what not to do:
- Use an orbital sander to wiggle the jar. It’s super load loud and doesn’t do much.
- Add water. This just gives you corroded LEDs that arent even diffuse.
- Run it with so much power that centrifugal force sticks everything to the sides and it vibrates itself off your desk overnight.
- Run it with so little power that it stalls.
- Fail to own a variable power supply so that your only choices are 12V and 9V (see above).
- Make your first shaft coupler out of gaffer tape. I ended up designing and 3D printing a simple shaft coupler.
Video: