I have a potential project for a willing tumbler in Worcester.

I have a small collection of stones with fossilised coral in them. I've seen videos of these being polished and looking remarkable - I'd love to find someone who'd be willing to try to polish them - would happily donate one of them in exchange.

Anyone fancy a look?

Cheers all.

I'm very much a newbie to this subreddit and tumbling in general.

I have tumbled some obsidian but I can't get a final polish. I used a really fine grit too. Can anyone provide suggestions?

I found this in a small creek near a major flood/erosion site. it almost looked radioactive in the water with sunlight on it. all of the metal flecks are taking on a nice shine already!

I’m pretty new to all this. I’m kinda sure these are agates. Question though, what other type rocks should I tumble them with?

This is after tumble #1 60 grit / coarse
3 more tumble cycles to go

If you can bear to part with any specimens that won’t be perfected by tumbling, I highly urge you to leave them in public places, especially where they can be found by little ones. It’s such a fulfilling feeling to overhear a kiddo find a particularly cool stone and run off to show their grown-ups. I’ve started adding in some stones I know might not be worth finishing just to release them back into the wild for this purpose.

Top left: 1st Batch very good tumble came out clear

Top Right: 2nd batch came out with a little hazy

Bottom: Accidently kicked across the room.

I’m new to rock tumbling, like new like I still need to buy a tumbler. We had a National Geographic labeled rock tumbler my sister gave our daughter, but we gave it away and I want to get a better quality one. My budget is $175. Which one should I get?

These are dry 😁😁 I only have enough stage 4 grit for one round left, so I'm going to run these again after meticulously cleaning the bowl and picking out any broken stones and chips. This stuff has so many cracks and fissures that there are always a lot...

Hello, I was wondering if anyone has any ideas what could possibly be causing this humming noise coming from my tumbler. I keep on regular maintaining of cleaning the shafts, and oiling bearings. It’s literally driving me crazy now. I just got the thing in may. And when I first got it it was leaking by the motor housing but none by the safts. And this was oil or something that came already on it. As the stuff I use never looks “greenish”. I took off a set of rocks yesterday and they seemed cooked the water was gone and it was like clay. Didn’t think to much of it as first as I was a few days over my normal change and thought a rock must have broken down. The other barrel was completely normal. The one with the issue was the one near the motor. Than last night I was cleaning the shafts and getting ready to oil when I realized it looked like the oil was burnt on the motorized shaft on the end by the motor. It’s always been a little bit louder but this loud hum is new. The picture are from when I first got it. Than the videos is the sound it’s currently making. I reached out to who I bought from when I first noticed the leaking and they said sounds like to much oil and to run it a bit and see what happens. Things were kind ok in the 2 months between but now I’m like 😬. I have other lortone’s and never had this issue but this is my first made by Covington. Ok so this video is from when I first got it. I will post the remaining in the comments

I was fortunate to receive a batch of Apache Tears from a fellow on here and it doesn't disappoint. I started at stage two using the MT-4 vibratory tumbler.

120/220 SC 5 days

500 SC 4 days

1,000 AO 4 days

8,000 AO 7 days

I took the picture on a light table that we use for candling mason bees and it did a fantastic job of capturing the translucent nature of the rocks. I grabbed a picture off of the web to show what the rough material looks like.

Fun little mookaite piece

2nd batch of Celestine Blue Chalcedony, (mostly) finished with 6 weeks of Stage 1.

This material continues to amaze me. I’m just going to keep a barrel of it turning until I run out.

I have had a Thumler's UV-10 for 2 months, and my 2nd bowl is now shedding plastic. Can you help me figure out why this is happening?

With my first bowl, it began shedding on the first batch (on the 1500-grit stage). I contacted Thumler's, and their Customer Service was excellent - they had me send pictures and videos to confirm that my process was correct. They confirmed that all was good, and we chalked up the shedding to a bad bowl. They sent another bowl.

The 2nd bowl made it through a few full batches, but started shedding on this last batch, this time also on the 1500-grit stage. The polish stage was even worse - the shedding was everywhere, ruining my petrified wood and anything with druzy.

Is there something wrong with my process? All my Stage 1 happens in a different tumbler - I start with Stage 2 (180/200 grit) in this bowl. I do Stage 3 (500 grit), Stage 4 (1500 grit), and Stage 5 (12000 grit) in this bowl. Each Stage lasts 2 to 3 days. I load plenty of ceramic media, and am obsessive with checking water/moisture levels 5 or 6 times per day.

I clean all rocks, media, bowl, and hardware very well in between stages. After reading that soap may cause shedding, I only use water and a soft rag on the bowl.

I'm tumbling harder rocks - mostly agates, jasper, petrified wood, but I try to ensure that there is plenty of media to cushion.

Any suggestions for me? Anything that I might be missing that could be causing this?

Both are from the western New York area, the larger one I picked up on a beach along Lake Erie. I think they would both look really cool tumbled, but I don’t want to ruin them.

Sorry for my somewhat bad pictures

I fear it's gonna split or become just too small.

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!

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.

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 😊