Rock-Tumbler Rotary Tumbler Tumbling Polisher

Another rock tumbler?

Yes, but this time completely different!

With direct drive via a shaft coupling - no printed gears, no worn-out belts.
Easy to print. Assembly possible for everyone!

The component tolerances are set for a Bambu Lab X1C.
The rear shaft can be flexibly used in 2 positions - can sizes from 8cm diameter are suitable.
usable width approx. 17cm.
The rollers are printed in TPU, the rest in PLA.
Alternatively, you can use rollers from other tumblers, they just need to fit 8mm shafts.

2 threaded rods of 26cm or more
4 608 ball bearings
1 motor (geared motor 100-250 rpm) + power supply, possibly speed controller.
2 screws for the motor
8 M4x30 screws (or longer) for the frame.
A few M8 nuts for the rollers
A little adhesive for fixation.

Most of it is just plugged together, making it very flexible.
Simple, functional - my version - have fun :-)

A detailed article (also with application results) can be found here:
https://www.bastel-bastel.de/blog/index.php/2024/03/09/jogis-rocktumbler-poliermaschine-im-3d-druck/

The can + lid are optional, a coffee can, a pickle jar or other containers also work of course - just try it out!
The motor support is recommended for heavy motors - depending on the motor chosen!

Ideal for polishing graphite surfaces for electroplating - see the 3W (back: hand polished, unevenly transferred, stained,

Update 17.5.2026:
Additional print profile uploaded, v2 - for improved results:

I left the old profile as is, but read this first:

1. New motor mount: Replaces the old mount.
Now flush with the rest of the device at the bottom and no longer just hanging in the air.
More flexibility for motor mounting.
When printing, DO NOT print the old mount and print this one instead.

2. New rollers: in addition or as a replacement
The new rollers are beveled and go from 40mm outer to 28mm inner.
Print in TPU (any kind is fine, as long as it's soft. I used TPU for AMS)
Advantage of the new rollers:
Buckets / drums that previously slowly migrated sideways when rotating now remain perfectly centered due to the bevels.
Nothing runs off here anymore!
This also allows slightly slanted containers to be used.
Pickle jars or similar containers are no longer a problem.

Ideally, print the old profile, but use the motor mount from the new profile.
The new rollers additionally, or as a replacement.
The new v2 profile contains only the additional, new parts!

Have fun polishing

 

front: Polished with the machine - much better!)