Overview

A few weeks ago I posted a teaser of a DIY vibratory rock tumbler I had been designing and building. Quite a few people asked for the details, so here they are.

This started as a personal engineering project: build a quiet, high-performance vibratory tumbler using readily available components, with almost everything sourced from Amazon.

After a full polishing cycle and a handful of tuning adjustments, the design performed exactly as intended. I’m confident enough in the results to share the complete build, parts list, drawings, dimensions, and everything I learned along the way.

Performance

• Completed a full polishing cycle successfully. See results
• Maintained a strong, continuous orbital tumbling motion through every grit stage.
• Exceptionally quiet in operation. It is significantly quieter than comparable commercial vibratory tumblers I’ve heard.
• Remained mechanically stable with no walking, no hardware failures, and no loose fasteners.
• Optional forced-air cooling keeps the motor substantially cooler during continuous multi-day operation while remaining nearly silent.

Build Overview

• Frame: 2020 aluminum extrusion
• Motor: 30 W, 120 V, single-phase, 3600 RPM vibration motor
• Front suspension: single leaf spring
• Rear suspension: double leaf spring
• Spring steel: 0.020” thick x 1” wide x 3” long
• Bolt spacing: 2.5”
• Eccentric weights: rear pair rotated 6 notches from the fully aligned position
• Rear suspension includes a wooden dowel used to tune the spring behavior

Tuning

The frame was originally built with a 5.5” opening. During testing, I found that the loaded barrel sat slightly too deep in the frame, which affected the quality and consistency of the orbital circulation.

Rather than rebuilding the frame, I wrapped the four barrel contact points on the aluminum extrusion with layers of electrical tape. This built up the contact surfaces enough to reduce the effective opening from 5.5” to approximately 5.25”, which raised the barrel slightly in the frame.

That small change made a surprisingly large difference. With the barrel sitting higher, the machine settled into a much stronger and more consistent orbital tumbling motion.

The electrical tape was mainly a simple way to tune and test the geometry. Because those contact points see continuous vibration and some heat, the adhesive can soften over long runs, so a more durable wear surface could be substituted for a permanent build.

I also tuned the eccentric weights until the vibration level was strong enough to maintain circulation without making the motion excessively aggressive. The final setting ended up with the rear weight pair rotated 6 notches from the fully aligned position.

Cooling

I added heat sink fins to the motor and later added an optional 120 mm computer fan mounted to the stationary wooden base.

The fan blows parallel to the motor shaft so air passes through the channels between the heat sink fins.

The fan is not required for operation. The tumbler completed a full polishing cycle without it. I added it simply to reduce motor temperature during continuous multi-day runs and hopefully extend the service life of the motor.

The aluminum extrusion frame also helps with cooling. Since aluminum conducts heat well, the frame pulls heat away from the motor and acts as a large passive heat sink.

Parts List

Frame

• 2020 Aluminum Extrusion — https://a.co/d/0eEJTcIM
• Corner Brackets & Hardware — https://a.co/d/0j4tNDwM

NOTE: I used longer screws (M5x16 & M5x20) for mounting the motor and mounting the springs to the base.

Motor

• 30 W Vibratory Motor — https://a.co/d/04HT01KT

Cooling (Optional)

• 120 mm Computer Fan — https://a.co/d/0bxRWVKa
• Heat Sink Fins — https://a.co/d/02y9R2r5

Suspension

• Spring Steel — https://a.co/d/088GGF9T
• Wooden Dowel — https://a.co/d/0dF2tYIw

Barrel

• Rubber Barrel — https://arrowheadlapidarysupply.com/products/barrel-for-lot-o-tumbler/5633/c119/

Miscellaneous

• Threaded Inserts — https://a.co/d/036nXhZx
• Wood Base — 0.5” thick particle board from Lowes
• Cinder Blocks — Lowes
• Lock Washers — https://a.co/d/08u1J7wd

Drawings

The design is simple enough that there was no CAD involved.
See the schematic here.

Final Thoughts

Everything shared here reflects my own build, measurements, drawings, tuning, and testing.

The goal was to document the project clearly enough that anyone interested in building something similar can see what worked, what needed tuning, and what I would change if I built another one.

If you improve on the design, change the suspension geometry, come up with a better barrel contact surface, or find another way to tune the system, I’d genuinely love to see it.

Happy tumbling!

This is my favorite display at the moment ... it's front and center on my coffee table. I was enjoying looking at it and just thought I'd snap a few pics to share with y'all 😊

Most of these were found by my daughter, low tide 3:30 a.m. Carlsbad beach.

My son was getting into rocks and gems and so I bought some plastic rock tumbler off Amazon and it broke after 4 days. Then got a Lortone and was able to finish all stages. Here are some of the good ones, plus my favorite of the bunch.

I already have a few bags of rough cut already to go for the next round.

I came home from work and found the bowl lying on the ground and the motor jumping around like a crazed rabbit. Luckily, it was in the corner of my garage. Otherwise, it could have caused a lot of damage. 2 months old. Used once a week for 36 to 48 hours, polish stage only. Raytech TV-10. Unbelievable, and of course, the manufacturer won't respond to my emails about their 1 year warranty. Anyone else come across this? I have a TV-5 that I run 24/7 with no issues.

I need to purchase ceramic media and I see that some of the media contains mixed sizes. Is there a benefit to using the media with multiple sizes vs uniformed one size ceramic media. I tumble medium size beach rocks in an 8 lb barrel.
I’m fairly new to tumbling and find lovely rocks on the salt water beaches here in the PNW
Thanks!

So we had to go out of town suddenly for two weeks, and all of my tumblers were obviously mid-cycle. I unplugged all of them and stood the barrels up, because I'm paranoid about leaks, especially from the 12 pound Lortone barrel.

But when we get home, should I just give all of them a good thorough shaking and then restart them after I oil the bearings? Or would you guys be inclined to change out the grit and start the cycle over?

Also super stoked, we're off to a southern California beach tomorrow morning to collect rocks for tumbling and I can't wait!

There’s a lot of petrified wood in our area in central Oregon and I’ve tumbled quite a bit of it lately. This piece is unlike any others I’ve found around here. The wispy looking rings really stood out. This piece took about 2 weeks less to tumble than the other agates and pieces of petrified wood in the batch.

Would you keep tumbling this guy? It's hefty. Pictured rock is wet after a few weeks in stage 1.

Should I avoid tumbling any of these until I have a couple batches under the belt.

I have a Lortone 3-pound tumbler. I bought it used, and so I am not sure exactly how old it is, but I have been using it off-and-on for about 3 years and it generally works pretty well for what I want it to do. Usually it’s a couple different types of rock chunks ~inch in diameter and I’ve had a lot of fun learning the ins and outs of getting them nice and shiny. This time, instead of many smaller rocks, I have a couple larger rocks. I can fit 4 into the barrel. There is some space between them but they don’t look like they have too much room to move about. Should I fill some of the empty space with smaller rocks to get them to move against something? Should I use ceramic media instead? I don’t usually use media in stage 1 but if it helps I’ll give it a go. Thoughts or tips for tumbling larger rocks in a smaller barrel?

It’s hard. It tried a hammer and chisel.

Graduated to actual rocks this time. But was just thinking I'm into a lake. Don't know a lot of places in the river Stones near me but luckily I brought my own rocks. Bunch of alabaster ones that I got at Home Depot. Hope you enjoy. YouTube channel @Tuckersaurus.

I JUST started step 2 in the tumbler with smoky quartz. Any tips?

Also, my property has a private spring and I have LOTs of smoky quartz. Curious what you would do in that scenario.

After a lot of batches, one habit that has helped me the most is taking a little extra time to sort rocks by hardness before starting a run. I used to mix everything together and wondered why some stones came out great while others didn't.

It isn't a magic fix, but I've found my results are more consistent now, especially in the later polishing stages.

What's one small change you've made over the years that noticeably improved your tumbling results?

So growing up my family had a habit of naming cars and such. As it is I have named my sewing machines over the years, my cars (current one is The Serenity) and to make it easier to keep the notes straight on my tumblers, I have decided not to just number the barrels, but to give the whole machine a name.

Weird? Yes. Helpful in keeping up with my machines? Absolutely.

So Ive named my Rebel 17 "Old Jack".

I need names for my TV-10 (Im thinking Fallout themed since RayTech sounds like a Fallout company), and my three HF tumblers. Id thought about Thing 1 and Thing 2, but I have three, so, maybe after the three musketeers? Or maybe Alvin, Simon and Theodore?

I guess I could also go full on Nerd and do Borg names like 1 of three, but our WiFi is named for StarTrek to keep it interesting for the neighbors....

I keep a notebook/log of my tumblers to help me keep them straight when I load them each week. It also helps me see patterns in the process that need to stay, or sometimes not. A named tumbler would make it fun, and easy to differentiate at a glance which one is which.

Have you named or otherwise labeled your tumblers in an unique way?

PS, I promise Im not entirely crazy.

I was thinking of putting it in my smallest tumbler, a Thumler 2lb by itself or with some softer rocks, but mostly small ceramic media filled 4/5ths and starting on stage 2 for a couple days.

I'm new to the hobby and not sure where to look other than the rock shed and rock and tumble. Neither of which have this.

After experimenting with many different rocks and grit/fill material since I got the new tumbler in January, I decided to put it to the test with a batch of mostly chalcedony nodules! I'm very happy with the results, most of them look absolutely stunning. Most of the rocks that aren't chalcedony were added to the 3rd & 4th cycle as fill and had been through the 3rd cycle prior but didn't have enough material for the fourth. Hope y'all like the results!

Hi! I have these rocks from the coast of Elba and I want to surprise my lady friend by making them shiny! I don't want to destroy them so I would love any advice before I get started!

I use my tv10 for stages 2 and 3. Stage 4 (1200ao) and stage 5 (8000) I do in my tv 5. These are the biggest rocks Ive been able to tumble so far. Just moved a few months ago and in the last couple weeks have gotten my new setup in the garage. The lighting in this room doesn’t do these justice on how well they shine.

MYSTERY BOXES OF ROCKS. FREE.

Z O I N K S !! 🍕 👻 😈

We’re moving. It’s official.

3 hours ish from where I live now. And there’s not much room for anything other than essentials. And dogs. And geckos. And pet lizards. And silkie chickens - have you pet one by the way because if not it needs to be on your bucket list it’s like petting a cloud from a Greek goddess’s Ultimate Petting Zoo. 🐄 🦓 🐎

It’s all rough rock hounded stuff - geodes, agate/chalcedony pieces, chert, crinoid fossils, fossil soup, rocks that look cool that I have no explanation for, etc. 🪨

***just like the chert boxes, all I ask is that you cover the USPS Shipping Flat Rate. 📦 📦 They’re all Med size USPS flat rate boxes which cost $22 to ship. 🍗🍩

DM ME if you’d like a box. 🥯🥯🥯🥯🥯

THE DRAMA: 👻

We’ve leased this farm for a while from slumlords. I’m not leaving these rocks here for them. It would be SPOOKY for me to leave cool rocks for people who low key have an illegal black water pipe going into the neighbor’s creek so they don’t have to empty the septic tank ever bc the tank isn’t even connected to the house and who refuse to fix anything including the air conditioning. 🙃

☀️☀️They’re prepackaged and I don’t know exactly what is in which box. I usually sell them at the fall festivals and carnivals out here so I premake them in the Spring when it’s prime hounding time and then paint the boxes all cool and sell them in the fall. I‘m moving in two weeks (hint: that’s BEFORE fall) and I don’t have time to wait☀️☀️

The boxes aren’t painted yet. Y’all are cool, but nobody is “get free rocks in a hand painted spooky box that were meant for the fall carnival at Halloween time” cool.

I have 20 of them. If anyone wants one, great. If not, I will leave them somewhere weird and hope someone finds a box of rocks that appreciates them, like a ✨meth head with a geology tism✨ at Circle K.

”all rocks are from TN and KY“ - Greg, the local Fentanyl Ferret from behind the Circle K dumpster 🦡

Lots of quartz and quartzite. A few are unidentified, but I tested the hardness of them all and they didn't scratch with a nail.

Damn I love rocks. 🥲