Rock Polishing Tips & Tricks

Above some roocks after a quick run of stage 2.  Most ended up getting redone. 



There are tons of guides about rock tumbling online.  Every single one offers something different so it can be a bit overwhelming to a beginner.  Want to know a secret?  Every single one of those guides is 100% correct....for the person that wrote it.  There is no "one way" to do things with tumbling, and a guide is simply that! 

Rather than try and reinvent the wheel, I thought I'd offer some tips & tricks to circumvent some of the common mistakes I see people make. 

1)  Don't let your eyes be bigger than your barrel!

Remember a barrels weight rating is meant to mean the weight of the rocks + water + barrel. Don't over fill it with rocks, or you will get a poor grinding action, and you will cause undue stress on your machine.  It's not fun when you break a belt in the middle of a tumble because you tried to push the tumbler further than it could handle.  You can tumble zero rocks on a broken tumbler.

Now, there is a little leeway in the weight, but use common sense.   If you fill the barrel 3/4 full and the rollers are struggling, remove some rocks.  If it spins perfectly fine, you're good to go.  Bigger barrels are bothered less.  For example, my QT66 can handle about 15 pounds (rated for 12); my ancient single 1.5 pound machine starts getting upset at anything over about 1.75 pounds.  It's all relative.  

2) Ceramic media is awesome, especially if you don't have enough rocks to fill the barrel.  It takes up space and provides cushioning, and it's not that expensive.   It doesn't roll all over like plastic pellets, it's not stage specific and it lasts a long time.  It's also a useful tool for justifying a larger tumbler because you can always fill the empty space. It just needs to be "broken in". 

Run ceramic media in stage 1 along with rocks, or tumble it solo for 1-2 days with some coarse grit to smooth the rough edges.  Don't run it "fresh" except in stage 1 (it can scratch your rocks).  Treat ceramic media like a really ugly kind of rock; wash it with your rocks and carry it on to the next stage.  There's no need to separate. 

3)  Barrel cleanings or "How I Learned to Love the Slurry" (ROTARY ONLY!)

For stage 1, some people prefer to dump the barrel completely, clean the rocks & barrel, add fresh grit and fresh water.  Personally, i just pull out a few rocks, check them over, add fresh grit and set it back on the rollers.  If the slurry is getting thick, I'll dump out a little more of it, and fill that lost space with clean water.  Doing this prevents having to do a lot of dumping, and it also ensures all the grit gets used up.  It also helps prevent a certain rock hound from making a giant mess.... 

Once you're done the stage?  THEN dump out the barrel and wash everything thoroughly. You don't want to find out that there was coarse grit in your pre-polish stage! 

4)  There is no harm in re-running a stage, or running longer (or shorter) than your tumbler's manual (or even our own guide) suggests. Move onto the next stage when YOU are happy with how the rocks look.  Maybe you want a "rustic" looking rock with some character, or maybe you're after a totally smooth, glassy finish.  Choice is yours.  

5)  If your rocks are not starting to get a dull shine by the end of pre-polish run your load another couple days or a week, or even go back to stage 2.   Patience is key!!  As one of the most impatient people in the world, I hate to say it, but it's true. 

You can also try to burnish them by running your barrel with rocks, water, and a bit of soap (Ivory, Dove, Borax or similar - NOT detergent). 

I don't use detergents for two reasons; One, I was always told that detergent is not good for your barrel (I have no proof of that but why chance it?)  and number two, commercial detergent based soaps wreck my hands.  The rocks do enough damage, I don't need to pile onto it. 

6)  Pails are priceless.  You don't need expensive tools, but you can never have enough pails.  Also a good colander from the dollar store is super handy.  The most expensive part of tumbling should be the tumbler itself. 

7) "Buy once, cry once".  Quality is worth it.  It's better to buy a smaller, good quality tumbler than a cheap big one.  A big, cheap tumbler will cost you time and cause you frustration when it breaks.  A good quality tumbler can run for a year or more with only minor maintenance.  Lortone tumblers are our shop favorite; they're compact, quiet, good quality and parts are readily available.  

8) Free rocks are the best kind!

 If you just want to tumble for tumbles sake, practice your ID skills on random rocks found on the local alley or grid road.  You might find some gems, and you won't feel bad if you grind them away to nothing.  Plus, you'll also get to learn about your local geology when you start to ID them.   Grit is cheap and free rocks can make some amazing tumbles if you just give them a chance.

One of my favorite rocks is a (formerly) 20 pound chunk of basalt with a strip of quartz that a friend gave me from his family farm (see their photo on our home page).  Sure basalt isn't a super luxurious gemstone, but it let me experiment with hours of practice cutting, shaping and tumbling some home grown material.  Coincidentally, this brings me to my next point... 

9)  Just because you can tumble it, doesn't mean you should.  Not all rocks will polish in a tumbler. 

Some rocks will work better in a rotary tumbler, some will work better in a vibratory tumbler, some shine up in either one..... and some rocks just suck.   Blame Mother Nature for that one.  Sometimes you get a lemon (or a dalmatian stone).  Some rocks are pretty even though they don't shine, and some shiny rocks are kind of ugly.  Beauty is in the eye of the beholder. 

10) Last but not least, and as I often tell newbies, experiment!! You're not going to mess it up.  You're going to learn.   Ask questions.  Every single rock hound started out where you are so don't feel bad if you don't know.  The experts weren't born experts! 

Hopefully these tips can save you a bit of headache when it comes to tumbling your rocks..  A lot of methods depend on your time, your rocks, or your tumbler. Don't get discouraged if you don't get the results you want, you can always re-run the tumbler.  Remember, through coarse grit, all things are possible :-) 

What are some of your tips & tricks? Share them by commenting! 

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