Rotary Rock Tumbling
Learn the exact ratios of rock, water, and grit to turn rough stones into polished gems in your rotary tumbler. Master barrel loading, protect your motor, and avoid cloudy rocks.
Like Duolingo, but for Rotary Rock Tumbling. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
A short one: 9 levels across 2 sections, about 18 minutes end to end, roughly 4 days at five minutes a day. It moves through The Barrel Recipe and Setup and From Rough Stones to Mirror Polish. It starts from scratch.
Free forever · No credit card · iPhone & Android
Key ideas in Rotary Rock Tumbling
- A tumbler barrel needs to be between two-thirds and three-quarters full of rock to create a continuous sliding wave
- Underfilling leaves too much open airspace, causing stones to crash into each other violently and shatter
- Overfilling packs stones so tightly against the lid that the entire load binds up and won't slide
- Grinding happens at the contact points between moving stones
- Uniform rocks create large, open voids between them with very little surface-to-surface contact
- Mixing large, medium, and pea-sized stones lets smaller pebbles fill the gaps and grind against every face
- Water should only be added until it barely reaches the bottom edge of the top rock layer
- Filling water too high creates a hydraulic cushion that floats the rocks slightly apart and dampens abrasive contact
- Water's main job is simply carrying grit into a paste across the stones, not floating them
- A standard three-pound rotary barrel only requires 2 to 3 level tablespoons of grit
- Adding extra scoops of grit does not speed up tumbling; the excess cannot stay in the grind zone and sinks uselessly to the bottom
- A 'three-pound tumbler' refers to the combined weight limit of the barrel, rocks, grit, and water combined
- Exceeding the total weight rating strains the small motor, causing it to run hot and eventually burn out
- Overweight barrels slip on the drive shafts or cause drive belts to stretch and break
- Moisture or grit on the rubber rim prevents a tight waterproof seal
- Wiping both the barrel rim and inner lid dry stops crust from building up and leaking
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives Rotary Rock Tumbling the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
How full should ye load your rock tumbler barrel with stones for a proper voyage?
Get it right to open this lesson and 8 more in the app.
Where Rotary Rock Tumbling takes you
- 1
The Barrel Recipe and Setup
- Loading the Barrel: Rocks, Grit, and Water
- Operating and Caring for the Machine
- 2
From Rough Stones to Mirror Polish
- Progressing Stages, Filler Media, and Cleanout
2 sections · 3 units · 9 levels. Built to play, not to enroll.
Tomo is in ChatGPT
Tomo is also a ChatGPT plugin: the same playable courses, built and played inside your chat.
Add Tomo to ChatGPT- What to ask
- “Make me a Tomo course on black holes.” “Turn this chat into a Tomo course.”
- What you get
- Quick questions with instant feedback, hearts and stars, ready to play in about a minute.
- Where it goes
- No sign-up to start. Connect your Tomo account and your streak carries on in the app.
You pick the voice
Rotary Rock Tumbling is taught in the The Pirate style: arr, learning be an adventure!. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
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Start Rotary Rock Tumbling today.
Download Tomo, search Rotary Rock Tumbling, and play your first lesson in under a minute.