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View Full Version : Vibratory tumbler - How Big?



Ben Diss
05-03-2004, 09:05 AM
I want to debur and polish aluminum pieces that are 1" round and 3" long. I want a fine mirror finish. I'm leaning towards a vibratory tumbler, but don't know how big a unit I need. I'd like to run 5 or 10 pieces at a time.

How big of a drum do I need?

-Ben

DR
05-03-2004, 12:52 PM
Hmmm....mirror finish on aluminum, huh?

Sounds like you'll need several tumblers with progressive coarseness of media. Or else, you'll need some fool proof way of cleaning every last bit of abrasive out of the machine between media changes (easier said than done).

For the final finishing you need some kind of buffing compound mixed with something like sawdust. Even then, it may not be possible to get a mirror finish in a tumbler.

As to the size of barrel, there's a formula which I can't remember now about the ratio of part volume to media. The important thing is to have enough media so that the parts themselves don't bang into each other causing dents.

Ben Diss
05-03-2004, 01:03 PM
I think it's either 30% or 40% part to media ratio. What I don't understand is how the size of the individual part comes into play with the shape of the bucket.

The finish doesn't have to be a perfect mirror, just shiney. I can get it that way on the lathe, I'm just hoping to save an hours labor on each part.

FYI, I'm making a tow release mechanism for model airplanes that tow model gliders. These will be "trophy" parts that will used as awards and raffle prizes. There is no way to economically make them, so I decided to make it a project of passion and produce the best looking tow release ever made and give them away selectively. It is 1" piece of aluminum rod, 3" long. There is a 3/32" hole through the center, through which a steel rod runs. A groove is cut laterally deep enough to go past the hole. A piece of string is passed into the groove and captured by the steel rod. The top will be rounded and the lower one inch will be lightly knurled to allow epoxy to have something to grab onto. The top exposed part will be polished to a glossy shine.

-Ben

Rustybolt
05-03-2004, 03:04 PM
Ben. Before jumping in with both feet, even small(1cu/ft) vibratory tumblers will run about 800+ dollars U.S. Smaller ones are available as brass tumblers sold to ammunition reloaders. These run about 100 dollars.As I recall media ran about a dollar a pound and you can change it to match the finish you desire.
You might wqnt to put it where it can't be heard. They can make a lot of noise.

Ben Diss
05-03-2004, 04:45 PM
What about one of these?

http://therockshed.com/tumbler3.html

Rustybolt
05-03-2004, 05:43 PM
Thats what I'm talking about.

gunsmith
05-03-2004, 06:27 PM
You might be going about this the wrong way? I polish aluminum on a regular bassis and to do a piece of aluminum the size you describe would take about 5 minites each on a buffing wheel. You might also include using a small sand blaster for the pre finish which would eat up about two more minutes. Every thing you are looking for can be found at the Eastwood automotive site.

Ben Diss
05-04-2004, 02:30 PM
OK. I ordered some buffing pads and compounds from Eastman. I'll try that first. Maybe I was using the wrong stuff before.

-Ben

jfsmith
05-05-2004, 08:32 PM
I have both sizes of Dillon Tumbers, they work fine. I get ground walnet shells from Petsmart, much cheaper than the reloading stores.

Jerr