Rock tumblers

I want to train my pet rock to be an acrobat.

What, not that kind of tumbling? Oh.
What do I look for in a rock tumbler? I don’t want to go into the shiny rock business, I just want to impress the Dudeling with my insane magic skills (anyone notice how easy it is to impress a three-year-old with magic?). I’m not all that concerned with noise (though my passive aggressive side wants to use the guest room, there’s plenty of space in the basement). I’ll do a few batches here and there, but that’s about it. Prices are all over the place—will the same toy model I had when I was ten (same as the basic forty dollar units) do, or is there a noticeable difference between units?

Don’t we have a geologist or two on the Boards? Lou?

I don’t think that there isn’t much to take into account for the purpose you want to use it for. Rock tumblers are just a motorized container that rotates so as long as it does that, you are good to go. I don’t know if you remember how noisy those things are, but they are fairly loud and you have to run them for about 3 weeks straight 24 hours a day to produce one batch of shiny rocks. The more expensive ones may be quieter but you can effectively silence even a cheap one by putting it in a cooler and closing the lid if you can still hear it from your basement.

I would just like to point out that sit and stay are the two easiest tricks to teach a pet rock.

Thanks. Noise really isn’t an issue. If the basement doesn’t work out for any reason, there’s always the garage.

So maybe there’s a small difference between capacities (within reason), but not a big difference in time needed or how well it turns out the priceless gems.
ETA to Rick: I’m way beyond that. A few years ago I told it to grow moss, and it did. I got this heroin thin slice of mica.

This is what you should be concerned with. They make a lot of noise. A lot, maybe most of it is from the reduction gears, so get those lubed up well. When you’re done all you have is some polished rocks.

They have a couple at Harbor Freight, probably around the same quality as the hobbyist models, maybe a bigger unit for the price though if you care.

I’ll bet you could make something out of an old drill driver that would do the job, and maybe make less noise.

The units with rubber chambers are more expensive, but a lot quieter, Thumbler’s Tumblers are probably the most popular models. The units with plastic chambers are a lot noisier but much cheaper.

One thing to do is some research of the materials used for the 4 stages of polishing - its a lot cheaper to get them on your own than buy ‘refill kits’.

I have the basic Thumlers Tumbler and it’s fine. The basic three pound barrel size is a good one. It takes too much rock to fill sizes larger than that. Get a few of the “grit packs” too.

When I was a kid, my dad rigged up a rock polisher using an old record player and a coffee can. Wasn’t perfect, but it worked well enough.

Most geologists don’t really have a lot of call for rock tumblers, that’s generally more a hobbyist thing.

Now diamond saws, we be all up in there.

Back in my misspent youth, I took a few rocks for a tumble. One thing that impressed my young and impressionable mind was the warnings about the slurry…the leftover corundum-grit-rock-dust-and-water mixture that comes out afterward. There were all kinds of warnings that pouring it down your drains will cause them to clog up permanently, and pouring it out in the yard will kill the grass. So investigate disposal methods before you have to have MrDibble snake your pipes with diamond-tipped plumbing tools.

I have a tumbler I got from Harbor Freight for about $35. It’s their cheap made-in-China tool brand, Chicago Electric. It has a rubber barrel, so it is pretty quiet. (I run it in my basement and I have to stand at the top of the stairs and actively listen for it to make sure it’s running.)

The one caveat I ran into on teh internets about this particular model is that it eats belts. Sure enough, the belts that came with it broke without a whole lot of hours on them, but I bought a dozen on eBay for a few bucks, and those seem to last much longer.

Just one caveat here. I bought a rock tumbler because I had dug up some rocks in the backyard that looked like they would polish up nicely. Ran it for a few weeks and ended up with rocks that looked almost as nice as what I could pick up by the truckload for free from any ocean beach.

So…does this make my vague plan to find nice rocks at the beach to polish dumb, then?

I’m getting pretty polished stones that started as rounded river beach stones. Having them highly polished and not just roughly rounded exposes all kinds of beautiful detail. Round is not the same as glossy.

Make a list of folks you don’t like!

Any way to equate the noise to something common? A vacuum cleaner? A Roombah? We have plenty of room down in the basement, which is used primarily for storage and the occasional “guest” (haven’t had a guest in a while since Precious died, but as soon as we get a new basket-pulley system worked out things we’ll look into a new dog).

The pathways in our gardens are river rock–a smoothed, smallish pebble. Wetting them and looking at them with a hand loupe shows some great detail. I imagine polished will bring out a lot. Any preferred guide to what can go in a tumbler? I have some azurite I collected in Arizona. But it seems a bit crumbly–wouldn’t I just end up with blue slurry?

They don’t sound like a vacuum cleaner. They sound like a tiny cement mixer or a little like a quiet garbage disposal with stuff in it. They aren’t extremely loud but it is an annoying sound if you have to listen to it 24 hours a day for weeks straight.

Yeah, it’s the 24/7 part of it that gets you. But there are recommendations for rubber chamber models here, that might make a big difference.

I’ve seen some fairly dull stones have their highlights brought out by polishing wth mineral oil. A lot of striated river stones will look surprisingly nice after tumbling. But they may be harder than the typical ‘pretty rock’ and take longer to tumble.

I’m tempted to get one of those rubber chamber models and try it out. Thinking about it, I have an old motor for a barbecue rotisserie, if I could find a small rubber container I could rig something up with that pretty quickly. I’ve got some aluminum oxide sandblasting media that should do for a first pass. Damn you Rhythmdvl! Stop putting ideas in my head.

I don’t know. Maybe my tumbler was crap, or maybe I did it wrong… or else the rocks were just not the right type.

I vaguely recall that you are supposed to run several stages of tumbling, using progressively finer grit, and rinse the rocks between stages so the larger grit is removed. This results in the glossy polish.

Perhaps you only ran one stage?