Cement mixer, other large tumbler options?

I have and I agree! To the chagrin of my auto shop owning Dad who wishes he had a son to take over his business, I was born with my mother's brain, which struggles with do-it-yourself tasks, haha. But I'm game to try given the time and instruction.

The generosity and helpfulness of the members of this forum is astounding indeed. It's just great to see so many people interested in rocks. I bring it up with anyone in my normal life, it's like I'm talking about aliens. 

I don't think it turns fast enough. But it has a large diameter to get a long slide, which is where the work happens. So, it may just take longer. The basic design is used one Covington tumbler,


It may also be subject to drying gout, and difficult to clean between grits. Not easy to have a different barrel for each stage.

People have also put 5gal buckets on a motor



PVC might last a little longer then plastic buckets: forum.rocktumblinghobby.com/thread/4197

I built one very similar to the one above using the angled 5 gallon bucket, but used 12" P.V.C. for the barrel; had to try it. Made it adjustable from 30 to 45 degrees angle and run it about 25 R.P.M. The first time I loaded it with some fairly large really blocky mtl. All the rocks held hands with each other, and the more I put in, the less movement I had. Second load was a bunch of pretty small rounded stuff, tumbled great. I think the angled barrel idea is best suited to fairly round, like water worn, rather than blocky, rough-edged things. I tumble our big rough rocks in a horizontal 5 gallon barrel set made of 12" P.V.C. pipe, each a foot long. Have a barrel for each stage, and run 2 at a time.

Use barrels of some sort. Cement mixers are made to mix, too violent. Tires to violent.
Figure out a large cylindrical barrel that has about the same scale as a regular tumbler.
Steel works great. Many big tumblers I see use steel barrels.
If I was tumbling a lot of material I would make like 8 foot shafts and put a bunch of 8 inch diameter barrels on it.
Single heavy barrel is heavy. HEAVY.
Larry(quartz) chined in above. He is up to 12 inch barrels. He could probably kick our arses if he handles those w/out a crane.

My advice is to bite the bullet and buy a 40 lb tumbler.  At that size, you need to have some flat sides in the barrel.  Small <3 lb round tumblers are about the max for round barrels.  I think a cement mixer drops the rocks too much and you will get cracks and spalls.  SiC grit would wear steel barrels out really fast too.

Thanks very much, everyone. Glad I got this advice before renting the mixer. Interested to see how your experience goes, blessed. The homemade tumbler ideas are great, and I think within my technical capabilities. I really appreciate the detailed advice!

This wood based tumbler runs like a charm. It had a 50 pound PVC barrel for years. One inch solid shafts. Parts all from Industrial Surplus in Lincoln, Nebraska.
Uses a 1/8 HP 1075 RPM A/C fan motor. 2 inch motor pulley and 12 inch big pulley. 3/4 inch shaft would suffice. I think I have $140 in it. Quiet wood frame easy to make.

Same tumbler as above but modified to reality. love this tumbler. Back shafts run fast for coarse. Front shafts run slow for finish and sensitive materials.
Metal a pain in the arse, wood frame is fine. (over)Built out of junk from boneyard. Three 16 pound barrels and one 50 pound barrel. Will work your arse off.

James,,,I never understood the theory of using a big tire for a tumbler barrel.It seems to me to be totally against the way the rocks are supposed "tumble" on top of each other and not just fall on top of each other.
The tumbling action in a "normal" barrel occurs just as the rocks come up to about the top of the barrel and "slide" down on top of each other,,sort of like a wave cresting on a shore.
With the tire tumblers the center is sealed off and I "think" some of the rocks carry over the top and crash down onto the top of the other rocks at the bottom of the tire????This would be especially true if the tire was filled with too many rocks.
What say you?
connrock