Rock tumbling to achieve smooth 3D printed parts.
Step 1: Purchasing a Tumbler
Practically any tumbler will work but spending a bit more can get you not only more reliability but also the ability to finish larger parts.
Step 2: Choosing a Media
Media will largely depend on the size and how detailed the part is. We found that crushed gravel was a good balance between size and finishing capability. Tested using crushed glass but it had no impact over 24 hours.
Step 3: Prep Phase
Fill the tumbler with enough media for it to cover your part, next add water until the water is slightly above the media and part.
Step 4: Tumbling
Tumbling times will vary depending on size and the amount of detail of the part, based on our tests we found it best to tumble for time periods of 24 hours and then check the finish that has been achieved before adding more time.
Step 5: Results
Stop parts at desired finish, oiling or painting your parts at this point will be much easier. We found that ABS would take significantly less time compared to PLA and PETG.