Alex Bealer Blacksmith Association

Dan, find one of the mini concrete mixers, which have a plastic drum. That dampens the noise. Or you could find ways of not fighting rust, that is if the metal is not used outdoors. Use ferric chloride to give the works a nice looking light brown patina. Wash off and seal with clear matte acrylic. For the case where you cannot clean the cracks, nooks and crannies use primer (for sacrificial corrosion) and then use compressed air and spray in Penetrol (available at ACE hardware) and finish painting. Also, remember that only the brown rust propagates rapidly. The high temperature blue and grey oxide is much more stable. For indoor work often I just leave it in place and paint with black acrylic (matte or satin - high gloss looks cheap!)
Dietrich from the hills.

I've mulled the concept of trying to build a quiet or sound-dampened tumbler by boxing one in with sound foam. I'm still trying to figure out what to use as a tumbler container.

Anybody got a good guess or experience with what kind of minimum wall thickness do you need for a tumbler?

Don't know if this is true, but I was told that to get rid of heavy, crusty scale, hit the scale on the cooled piece with an oxyacetylene flame and it will pop off. For light scale, I have used a strong solution of ph down for swimming pools. After use, neutralize it with baking soda before disposing of it.

Linda Holmes-Rubin

My wild guess on wall thickness is 1/8 inch being plenty for a tumbler. Back again to the concrete mixers. The ones I am familiar with (I assembled them, long ago, to make money, as a student)use about 1/16th material. Remember, however, that concrete mix is plenty abrasive, but cumulatively you don't run them as long as tumblers. One version of Shean's or Dan's sound damping could be a foam lined plywood box you set or slide over the tumbler. McMaster Carr (catalog or website) gives you guidance on what types of sound deadening foam you could use. Depending on the power for the tumbler you may have to vent the box to avoid heat build-up. For both vent inlet and outlet add a 90 (or greater) degree bend and line the inside bend with foam, so that sound power gets absorbed when it has to take the curve. How about a plastic food drum with a lid? You could find them under farm supplies in the farmers market bulletin. Place it on four rollers and wrap a bicycle chain around, which you fix to the drum with clip angles. And rotate it with a powered sprocket. Keep the drum weight against the sprocket, so that it does not push itself out of engagement. Probably have to countersink the screw heads for the clips from inside the drum, so that the screw does not get abraded. These drums are typically made from UHMW plastic, which is very resistant to abrasion, plus, noise damping. Keep us posted on your success.

Dietrich in Rabun

When I visited Joe Miller's shop in Brasstown, he had a home-made tumbler. Maybe give him a call and ask about it. As I remember, he built a cylinder with fins inside, and ran it with an electric motor. It did a very nice job on his hooks, leaves and small candle sticks. This also sounds like a good workshop topic. I have a few motors from woodworking equipment, maybe a few of us could build tumblers.

Linda Holmes-Rubin

I too have several idle electric motors that could be used for this purpose, BUT they are 1760 RPM. Using belts and pulleys to slow this down enough is CRAZY. I have wondered about the same concept as the tire hammer. A small drive wheel attached to the motor shaft that rubs against the tire. This has the same disadvantage of a large tire at on end of the tumbler, but it seems SO SIMPLE. Any other thoughts on how to slow it down without a fortune spent. I AM CHEAP!

SEAN O SHEA What about corrugated metal culvert material for a body of a tumbler? THE UNCOATED type. It is what I was considering. It comes in different diameters and, I THINK, in different metal thicknesses. With the corrugations it isn't particularly pretty, but then neither am I. I think I know where I could steal a piece and that is why I have considered it.

well if you have a lot, bring to me and I will sandblast it. Just so everyone knows I am doing powder coating now. I have a 4' wide x 6' tall x 8' deep oven