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gzig5
01-08-2011, 12:55 AM
Looking for suggestions. I'm thinking about building a rotary tumbler like the Thumbler's model B that would hold 10-15 pounds of material. The Thumbler's sell for about $200 shipped which isn't horrible, but it isn't free either. The frame and drive are no problem and I have appropriate motors. I'm struggling with the drum design which is typically faceted and includes a molded rubber liner that seals water tight when the lid is clamped on. I can bend up and weld a drum, but what to do about the liner which looks something like the one in this pic and sells for $55?

http://www.provision-resources.com/shop_content/prod_img/full/d0fe804e9e00457adc35cce1e143ecb5/2cfc65ca78f5e6b21e0a978fed66ee9f/12Tliner-w.jpg

I'll mainly be tumbling brass rifle cartridges with little stainless steel rods as media in a soap solution, so it needs to be water tight. I think the rubber liner is there for reducing noise and the think could be made to work without it, but it would be loud. The HF ones I have seen are too small.
Greg

ulav8r
01-08-2011, 01:10 AM
Years ago I bought a roll of rubber-like gasket material to line a blast cabinet. It would also make a good liner for a tumbler. It was about .1 thick.

ZINOM
01-08-2011, 01:20 AM
Might sound stupid but don't some places spray on undercoat (for cars)?...that might be an option...no?

Or some of the spray can stuff from places like Eastwood.

Probably not worth the 2 cents I put in actually :(

John

Bruce Griffing
01-08-2011, 01:32 AM
I am just brainstorming, but wouldn't spray truck bed liner be a good choice?

Cobbler
01-08-2011, 01:52 AM
I built a rotary tumbler using a treadmill as the basis for the design. For the barrel I used 8" PVC with some plastic ends I turned on the lathe. Mine has 3 plastic paddles made from some 1"x1" angle screwed to the inside of the barrel. There are photos and some discussion of the project here...

http://garagegunsmithing.com/forum/viewtopic.php?f=31&t=542

I would bet with just a slight re-design of the through bolt and an O-ring on each end cap and it would be reasonably water tight.

Why do you tumble them wet? Everyone I know uses either ground walnut shells or ground corn cobs.

dp
01-08-2011, 02:12 AM
Get a large PVC 4-way cross connector, put 6" stub pipes on each connection (forming a big "X"), fill with your work, abrasive and fluids, cap with threaded caps, spin slowly for a while.

One of the strangest tumblers I've seen is a car tire mounted on a rim and attached to a spindle with motor. The tire had been drilled on the sidewall and a pvc cap attached somehow to allow access. Obviously not pressurized. The stuff would go in there and the tire would rotate at a slow speed for as long as it took. It was large, but dead quiet, and had huge capacity. I might consider a tire from a utility trailer.

Image of a cross connector:

http://www.littlegreenhouse.com/accessory/p-cross.jpg

Boucher
01-08-2011, 09:20 AM
Would a small cement mixer work?
http://www.harborfreight.com/power-tools/mixers.html

gzig5
01-08-2011, 10:06 AM
Why do you tumble them wet? Everyone I know uses either ground walnut shells or ground corn cobs.

That's what I used to do when I started, then I went to ultra sonic which works great but needs small batches, and now this. The brass comes out looking like new, no matter how dirty inside and out. Media doesn't stick in flash holes. The water solutions carries away the junk and help cut the carbon.

http://www.ar15.com/forums/topic.html?b=6&f=42&t=311325

There are a few sources for the media which costs about $10/lb delivered. Expensive, but will last a lifetime or two.


The big PVC pipe will work if I can find a short section for a reasonable price. If I have to pay $50+ for material for the drum I might as well go whole hog and get the Thumbler's.

gzig5
01-08-2011, 10:08 AM
Would a small cement mixer work?
http://www.harborfreight.com/power-tools/mixers.html

Yes, it would and there are high volume guys that use them, but it is about 10,000% too big for my needs. I'm talking about a drum 8-10" in diameter and about as tall.

Highpower
01-08-2011, 10:41 AM
Would a small cement mixer work?
http://www.harborfreight.com/power-tools/mixers.html FWIW... Sierra Bullets uses small cement mixers sprayed with the truck bed liner material inside. They use ground corncob though for the final polishing on their bullets.

I'm a bit leery of using the little stainless "needle bearings" myself. Impacting my cases with steel sounds like a good way to work harden the brass. I can't prove that of course. :o
I do use a RCBS Sidewinder tumbler with similar drums for doing my moly coating though. Holds 10 - 15 lbs of bullets & stainless balls with no problem.

Boucher
01-08-2011, 10:47 AM
I am a retired water well driller. We had lots of short sections of pipe left over that were scrap. There are probably people in your area that will give you the pipe. Large caps couplings and fittings are expensive so it may be easier to make a sealable plug for the closure.

gzig5
01-08-2011, 10:53 AM
I am a retired water well driller. We had lots of short sections of pipe left over that were scrap. There are probably people in your area that will give you the pipe. Large caps couplings and fittings are expensive so it may be easier to make a sealable plug for the closure.

Good suggestion. There is a drilling outfit not too far down the road.

Duffy
01-08-2011, 10:56 AM
If you look into tumbler design and operation, you will find that cylindrical tumblers work just fine. It is all a matter of rotational speed vs load.
That said, why not use poly food drums? One example is used to hold Greek olives. It holds 15 kg, has a gasketted screw lid and is made from HDPE. Best of all, they are a single-use container and you should be able to get them for the asking at any good-sized deli.
If you want to get REALLY ambitious, these drums are also available, just a bit smaller than a 45 gallon, (55 gallon?) steel drum. They have the same screw lid and gasket. I have one rigged to collect rainwater for my orchids.

gzig5
01-08-2011, 11:05 AM
FWIW... Sierra Bullets uses small cement mixers sprayed with the truck bed liner material inside. They use ground corncob though for the final polishing on their bullets.

I'm a bit leery of using the little stainless "needle bearings" myself. Impacting my cases with steel sounds like a good way to work harden the brass. I can't prove that of course. :o
I do use a RCBS Sidewinder tumbler with similar drums for doing my moly coating though. Holds 10 - 15 lbs of bullets & stainless balls with no problem.

The process is quite safe for the brass. Rotary tumblers have been used for decades and the peening that occurs is no different than cases hitting each other. The cleaning action is more of a scuffing than hitting and the individual pieces are so light that it doesn't matter. It's not like they are coming in at 100mph. Plus the water solution slows everything down.

Gravy
01-08-2011, 11:33 AM
I'd use PVC pipe of a suitable diameter. Line with sheet rubber from McMaster or elsewhere. Cap with Fernco caps.

biometrics
01-10-2011, 11:27 AM
I made a tumbler years ago for dealing with brass cartridge cases out of scrap... it didn't cost me a cent.

I used ground walnuts hulls and a jeweler's rouge polishing compund mixture I made myself and the tumbler enclosure was simply one of those large tupperware type buckets that your local deli receives it's cole slaw or macaroni salad or similar type stuff in. They are about 10" in diameter and 10 to 12" high.

They throw them away so the price is right and plentiful if you need to replace them. I mounted a small ection of 1" plastic angle "iron" to one of the sidewalls so that the mixture would be better stirred as it rotated.

The device worked great and didn't make very much nose either... I would load it up, turn it on, and check on it a few hours later. I used a small fry-daddy type screen bucket to remove the brass cases without picking up too much of the cleaning compound.

I used a gear reduction from an old car window crank mechanism and mounted the shaft at a 45 degree angle to ensure constant movement instead of sliding of the media...

the device was powered with an old washing machine or dishwasher motor and the connection between the motor chsaft and the crank shaft of the gear mechanism was a piece of rubber fuel line that was clamped with bailing wire... alignment of the shafts was no problem because of the flexibility of the rubber hose. The whole frame was made of scrap 2x4's and plywood. The tumbler device lasted for almost two decades... I had to replace the "bucket" only one time because I stupidly dropped something on the edge of the installed bucket which broke the seal with the pop off lid... I stopped reloading about 10 years ago and just chucked the device in the dumpster because it was just taking up room in the garage.

Sorry I don't have any photos, but hopefully you can make something similar from my description.

madwilliamflint
01-10-2011, 11:34 AM
When I was a puppy I had a hobby rock tumbler with a pair of rubber 'barrels' about 6" internal diameter and height. Sounds like the right size.

something like these (http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=rock+tumbler&x=20&y=15)

Toolguy
01-10-2011, 01:52 PM
I shoot and reload quite a bit. I have several tumblers including the Thumblers, Dillon and RCBS vibratory ones and an HF cement mixer like the red one in the middle in post 7. The one that works the best and is the easiest to use is the cement mixer. The other ones all sit idle now, though I occasionally use the tumbler to deburr metal parts with ceramic stone media. I took the paddles out and it works better without them. I wish I had spent a little more and got the orange one with the plastic drum. When the weather warms up I'll spray the inside of mine with rattle can truck bed liner to make it a little quieter. I use about 20 - 30 pounds of walnut media with a bottle of car polish. Pour in the car polish and let it run for an hour or so before adding brass. Even old range brass comes out looking brand new. The plastic drum one would probably work great for your ss pin media.

lugnut
01-10-2011, 02:15 PM
This is a tumbler that I made last year for a neighbor Made from a ATV tire, works great.
http://img.photobucket.com/albums/v671/lugnut/Tumbler%20II/P1010008008.jpg
http://img.photobucket.com/albums/v671/lugnut/Tumbler%20II/P1010009009.jpg
He moved and gave it back to me, I have no interest in rock tumbling

gzig5
01-10-2011, 02:16 PM
I shoot and reload qui

What's "qui" and how do you reload it? :p

Rustybolt
01-10-2011, 04:07 PM
Devcon makes a liquid rubber you can just pour in.


I made mine(gone now) into the shape of a hexagon out of 5 inch square plates. I welded some steel axels on the ends and then borrowed a friends 16 inch lathe to turn the axels to size.

Toolguy
01-10-2011, 04:26 PM
I think that's the energy part of yin and yang. You reload it with excercise, good food and rest and a little ying yang now and then. :rolleyes:

edit - somebody sneaked one in ahead of me. I must be having an off day. Sheesh.