Tank Tumbler

[Creed]

I thought I would share my experience with building an el-cheapo tank tumbler. I am doing this entirely from memory, so don't quote me on the dimensions. I designed it as I built, so I don't have exact measurements.

It took a 1785(or whatever the standard rpm is) rpm motor(had one),
a couple of 2x4's,
some pulleys and a belt from the local farm implement store,
some rubber tape for the drive shaft,
a 3/8 inch 3 ft steel bar,
a pair of old roller skates(not inline),
and misc stuff like deck screws and whatnot.

First, I tore the aluminum wheel support(for lack of a better term) from the bottom of the skate shoes. Then, I cut the supports in half with an angle grinder, leaving me with four sets of wheels, with convient mounting holes. I took off the wheels, cleaned the shafts with steel wool, and packed the bearings with grease.

Then, I cut 4 36" lengths of 2x4, and two 12" lengths. I drilled a 3/8" hole through the smaller pieces. That was the support for the drive shaft. The longer pieces were the frame.

I guessed that 6" would be a good width for the tank to turn, and lined up the skate wheels accordingly. The motor mounted on the top, with a 1-1/2" pulley. It drove the 2-1/2" pulley on the shaft. Combined with the 3/8" diameter of the shaft, that resulted in the tank turning at somewhere around 60 rpm.

It is an ugly ad hoc project, but it works fine. When I rebuild it(the next time I need to tumble a tank), I am going to change a few things.
1 - go to a 1/2" shaft. The 3/8" flexes somewhat.
2 - install bearing for the shaft. It works ok running on the wood with motorcycle chain wax coating the inside, but I don't trust it to run unattended for hours on end.

Pretty easy to build, and cheap if you can scrounge the parts like I did.

 

[DA Aquamaster]

I'd also consider changing the gear ratio a bit to reduce the tank rotation rate to 25-30 rpm. Much of the effect of the tumbling process occurs from the fall of the media in the tank. At 60 rpm I suspect that much of the media is staying plastered against the tank wall with comparatively little shifting or movement reducing the efficency of the tumbling process

 

[Creed]

I'd also consider changing the gear ratio a bit to reduce the tank rotation rate to 25-30 rpm. Much of the effect of the tumbling process occurs from the fall of the media in the tank. At 60 rpm I suspect that much of the media is staying plastered against the tank wall with comparatively little shifting or movement reducing the efficency of the tumbling process

Actually, with the media I used, it seemed to work perfectly. At 60rpm, it created a really nice wave looking effect.

 

[critterc]

what media are you all using ?

 

[Creed]

what media are you all using ?

I just went to the local river, and scooped up some coarse sand and gravel. While I was digging for that, I noticed a plethora of spent brass shells, mostly from .22 caliber pistols. I collected a lot of those, figuring that brass will strip lining but not harm the steel. There are also a lot of river clams in that area. I collected a lot of shells, and smashed the larger shells with a hammer, to make plenty of jagged, sharp edges. Totally free media. Just costs the time to collect it. If I wanted to make it faster, I could have brought a piece of metal fencing(the type with 1/2 inch squares) to use as a seive.

To sum up, small gravel, sand, crushed shells and brass.

 

[jbd]

I thought I would share my experience with building an el-cheapo tank tumbler. I am doing this entirely from memory, so don't quote me on the dimensions. I designed it as I built, so I don't have exact measurements.

It took a 1785(or whatever the standard rpm is) rpm motor(had one),
a couple of 2x4's,
some pulleys and a belt from the local farm implement store,
some rubber tape for the drive shaft,
a 3/8 inch 3 ft steel bar,
a pair of old roller skates(not inline),
and misc stuff like deck screws and whatnot.

First, I tore the aluminum wheel support(for lack of a better term) from the bottom of the skate shoes. Then, I cut the supports in half with an angle grinder, leaving me with four sets of wheels, with convient mounting holes. I took off the wheels, cleaned the shafts with steel wool, and packed the bearings with grease.

Then, I cut 4 36" lengths of 2x4, and two 12" lengths. I drilled a 3/8" hole through the smaller pieces. That was the support for the drive shaft. The longer pieces were the frame.

I guessed that 6" would be a good width for the tank to turn, and lined up the skate wheels accordingly. The motor mounted on the top, with a 1-1/2" pulley. It drove the 2-1/2" pulley on the shaft. Combined with the 3/8" diameter of the shaft, that resulted in the tank turning at somewhere around 60 rpm.

It is an ugly ad hoc project, but it works fine. When I rebuild it(the next time I need to tumble a tank), I am going to change a few things.
1 - go to a 1/2" shaft. The 3/8" flexes somewhat.
2 - install bearing for the shaft. It works ok running on the wood with motorcycle chain wax coating the inside, but I don't trust it to run unattended for hours on end.

Pretty easy to build, and cheap if you can scrounge the parts like I did.

Any pictures?

 

[Creed]

Any pictures?

I don't have any handy. I will try to borrow a camera and take a few this week.

 

[Hoosier]

Maybe, you guys might be interested in this one:

http://www.magnificentrelief.com/Tumbler.htm

She is also our member and so handy diver....

 

[Creed]

Maybe, you guys might be interested in this one:

http://www.magnificentrelief.com/Tumbler.htm

She is also our member and so handy diver....

I took some inspiration from (her,his, their?) design. My shaft runs through the center of the 2x4s instead of to the side.

 

[JustinW]

the larger tumblers that i have seen are on tables, and tilt so the media can concentrate on the neck or the bottom, as that is frequently where problems occur to start with.