# Rock tumblers **URL:** \ **Category:** Factual Questions\ **Created:** [July 22, 2012, 7:16pm UTC](https://boards.straightdope.com/t/rock-tumblers/629065 "2012-07-22T19:16:44Z")\ **Posts on this page:** 3\ **Page:** 2
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [July 26, 2012, 12:30pm UTC](https://boards.straightdope.com/t/rock-tumblers/629065/21 "2012-07-26T12:30:18Z")
> [@Rhythmdvl](#): > > 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? Good rock for a tumbler should be fairly hard (5 - 7 on the Mohs scale I think) and the entire load should be of similar hardness. The rocks should not have holes or little cavities because that can carry grit from an earlier stage to a later stage where it will ruin the finish. A typical setup is to use coarse grit for a week, then fine grit, then prepolish, then polish. But there are many variants on this scheme. Look around for some rock tumbling faqs - they’re out there. ---
**Author:** ![old\_joe](https://avatars.discourse-cdn.com/v4/letter/o/58956e/32.png) [@old\_joe](https://boards.straightdope.com/u/old_joe)\ **Post date:** [July 26, 2012, 7:17pm UTC](https://boards.straightdope.com/t/rock-tumblers/629065/22 "2012-07-26T19:17:34Z")
> [@Sailboat](#): > > 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? I did tons 🙂 of rock when my kids were small. I had a Lortone sp? tumbler with a rubber barrel. 3 pounder I beleive. You start with a coarse grit which I always left for a month. by that time the grit was effectively a medium size. Then you empty the barrel being very carefull to clean all the old grit off and recharge with the next finer grade of grit. Keep doing that until you get to the polishing powder, Aluminum Oxide i think and do that for a week or two. As I recall I did 4 steps over 2 or three months. My rocks came out looking like glass. I recommend you buy some agates for the wow factor. very very nice. Have fun. ---
**Author:** ![GargoyleWB](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gargoylewb/32/199_2.png) [@GargoyleWB](https://boards.straightdope.com/u/GargoyleWB)\ **Post date:** [July 26, 2012, 7:40pm UTC](https://boards.straightdope.com/t/rock-tumblers/629065/23 "2012-07-26T19:40:10Z")
I got a kit from these guys, we love it. It has rubber chambers, is very quiet (about like an electric toothbrush) and easy to use. Their kit comes with all of the polishing stage grits. We got the two barrel model so we could run different batches at different stages. The only thing that sucks is the patience required to let it tumble and do its thing. Lortone Tumblers [Previous page](https://boards.straightdope.com/t/rock-tumblers/629065.md?page=1)