I think I'll build a rotary tumbler...

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nemesiss45

New member
I have one now, but the motor is on its last legs, and the tubs have started leaking a bit... it is an old company that is out of business, so I can't get replacement parts. I think it could use a thumler's model B tub, but I don't relish spending $50, when the motor is going out anyway.


so here's my plan, and I'd love some feedback.

I have a table saw with a burned up motor, for which, no replacement motor is made anymore... I have been putting off taking it to the scrap yard, but now, I think it would make a great base for a tumbler. it is stable, square, and had an adjustable deck I could use to make my tumbler expandable for a larger barrel if I ever needed to. It has the switch and cord in tact, so I can just wire in a motor and be good to go. I also have a motor that should be more than enough to drive a large tumbler sitting in a crate also wasting space.

I went by a local Habitat for Humanity store (not sure how widespread these are... basically like a hardware thrift store, I love 'em) I picked up one of those cylindrical orange water coolers and several garage door track wheels.

concerning the drive mechanism, I have enough wheels, I can mount 2 of them on each side, mount the motor under the table and run a drive belt through the opening for the blade and over the whole cooler to drive it directly.

I am, however, more inclined to mount 2 wheels to support the non drive side, then get a shaft and 2 pillow bearings for the drive side. I'd then side mount the motor and run a v or toothed belt on pulley's to drive the shaft.

the great thing about the cooler as a tumbling vessel is that it has circumferential grooves that fit well with the wheels I got to keep the tub from drifting. They would also keep a belt in place if I choose that route. Also, when it wears out, a replacement should be available for just a few dollars. I just hope it doesn't wear out too fast. I know the plastic is thinner than the tub on my current tumbler and not backed with metal... but I figure worst case scenario, I will have to build one of the DIY PVC tubs that you see all over youtube. in the mean time, I think I will glue some agitators into the cooler so it is not just a smooth barrel.

as far as the drive is concerned. I still need to check my motor rpm to calculate the pulley size(s). I am also considering using opposed step pulleys so I can adjust the drum speed and possibly to be able to increase the speed enough to run a tub like a ball mill... but then I don't know if the shaft could drive a drum that fast without slipping... but perhaps I could put an idler wheel above the drum to maintain contact.... but that is a question for another day.


if anyone has any insight on a good rpm to shoot for, I'd appreciate it.
I'd appreciate any insight overall.

One question I have, for anyone that has made a larger tumbler, would bar stock work for the drive shaft, or will it flex too much? I was planning on buying a hardened shaft, but bar stock is significantly cheaper... and perhaps I could case harden some bar stock at home?

I will post photos as I go and maybe make a tutorial if it turns out well.
 
You are doing things the hard way. If I wanted to build a large rotary tumbler I would use a clothes washing machine machine.

You could probably find one with a burned out control board for next to nothing.

Pull off the front and remove the drum so that you can remove the paddles.

Then rewire the machine so it works off a toggle switch. Re insert the drum and put the front back on. You now have a big rotating drum that you can insert smaller drums into. You put the dirty brass and cleaning media into those plastic folgers coffee containers or multi gallon bucket that you can purchase from a eating place for a buck and a half.

I did this to one of those expensive mobile home size stack washers but I converted it to wash clothes. The board was burned out so I just tapped in a drain into the tub and use a ball valve to drain. I needed a spin cycle so I used an On Off On toggle so that I can kick in the spin cycle. No I do not have it here but it works fine at the cabin and it takes way less soap.
 
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perhaps, I feel like a washer is a bit more cumbersome than I want to deal with, plus, I have most of what I need on hand already
 
A front loading washer will take up the same space as a table saw.

You can still put things on top of a front loading washer BUT you can not do that with your contraption. You could build a shelf unit that would set on top that would hold a bunch of reloading stuff.

You have not ruined a table saw that someone with more skill can easily fix.

The converted front loading washer will hold multiple containers of seperated brass all running at the same time where your contraption is limited to ONE drum.
 
a table saw, I can stick on a shelf or hang on a wall, but for a washer I would have to find space for in my crowded shop, and I'm ok doing 1 drum at a time. I have only occasionally wanted to run more brass than my 1 gallon unit could handle, so the 3-5 that this new one will handle should be more than enough.

I'm not arguing your idea's merit. just that the one I am building fits my situation.
 
You want no more than 100 fpm surface speed on your container or the media will just go centrifugal and there won't be any tumbling action.
When I built mine I calculated it at 100fpm and it ended up at 99.69 and it works extremely well.

I put solid 5/8"shafts through mine with 2 bolt flange bearings on each end. I drilled the bolt holes for the flange bearings over sized on one end so I could adjust the bearings on one side to make the shafts parallel.

I then put 5/8 heater hose over the shafts and put them through the 1"holes in the frame.

I've been using this tumbler since 1996 and haven't had to do anything to it since I built it.
 

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Why use the table saw at all? If that size drum is large enough for you why not make the tumbler so it mounts on the wall? A quarter or a third horse power motor should be plenty. You could weld up a frame or if you can not weld simply bolt one together and figure out what speed reduction you need and purchase the appropriate sheves to get the RPM that you want for the drum.

I build all kinds of stuff out of scrap and off the rack hardware store stuff such as my shop elevator. I have the only private garage around with a one ton elevator.
 
a 1/3 hp motor is plenty, with the reduction of speed 1/3hp motor has so much mechanical advantage over turning the drum it doesn't even get warm.

Just make sure you stick around 100 fpm, that speed seems to be optimal.
 
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LE-28, thanks. your machine look spectacular.

hatcreek, I am using the table saw because it is light and portable, but also sturdy. It is a great size and shape for a tumbler and will allow me to move the unit around where I need it, but give me the capacity I want.

The saw is no loss to the world. it is a cheap Ryobi saw, and I could probably buy a working one used for less than it would cost to track down the discontinued motor (already looked into it) or to rebuild the motor on it. and besides, I still have my working Delta table saw that should last me years to come.
 
check this thread out on the castbolets forum.

http://castboolits.gunloads.com/sho...ler-Plans-with-Pulley-Size-and-Drum-explained

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I am using the table saw because it is light and portable, but also sturdy. It is a great size and shape for a tumbler and will allow me to move the unit around where I need it, but give me the capacity I want.
Click to expand...

I was amazed at how loud the tumbling brass is. I almost always load mine up and then wheel it outside. Besides that's where I rinse and separate pins from brass.
 
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nemesiss45; just say no to the washer, no sense in arguing about it, the pros and cons of each, you don't want to use a washer so don't! (I wouldn't want to use one either).

When I was looking to build a tumbler I googled "home made ball mills" and "home made rock tumblers" and got a lot of ideas...
 
Depends on your version of 'Large'...

I bought a 'Horror Fright' (Harbor Freight) cement mixer.
Lined it with the same semi rigid plastic used for cutting on counters,
Replaced the mixing blades with 1/3 sections of 2" PCV tubing.
Mixer, $150. PVC laying around. Plastic $3 a roll at the dollar store.

Dryer drum to sift out the pins from the cases, found a drum with slots instead of round holes, works pretty good...
The round hole drum didnt work so well.
Drums were free, $10 for bearing and about $30 for metal to build stand.
Goodwill kitchen mixer for drive power, $15.

Screen to catch the pins, laundry sink with no legs to catch the mess and send it down the drain.
Screen, about $5, can't remember exactly,
Laundry tub, $35 at home big box store.

Now, we all know that electric motors and bearings from Horror Freight won't live, so I figure it will run me $50 for an eBay motor and $10 for a bearing sometime in the near future... The next couple years.
But the built in cement mixer features are GREAT!
Pivots up, no water tight cover required,
Tips down to dump its cargo,
Center pivoted so you don't have to man handle the weight,
And is built for weights of 5,000 each .223 brass and 30 pounds of steel pins, PLUS the weight of the water...

Before that, I was running axles/wheels from skate board and 10" PVC pipe as container, clean out plug on one end, cap on the other.
1/4 HP motor & pullies/belts to reduce speed cost as much as the cement mixer...
 
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As for motors/speed, search eBay for 'Gear Motor'.
You will find all shapes & speeds for cheap to stupid expensive.

Remember something about gear reduction motors,
They trade horsepower for torque, a little motor will turn a large drum at low speed very easily,
You don't need a 2 HP motor or motorcycle chain drive for a tumbler.
About 30 to 60 RPM depending on the diameter of your container,
30 RPM for direct drive, if you use small wheels to drive a large diameter container, you are going to get more gear reduction on the drive,
So you can speed the motor up.
 
Washing machine is way too big. Even an apartment size.
I've seen tumblers made out of everything from coffee cans to metal/plastic 5 gallon pails. Easiest part to find is the electric motor. A variable speed electric drill would do for a small pail.
Normally, I'd say Princess Auto is your friend. Don't think they'd be any better than a surplus place Stateside though.
 
I made one out of an old treadmill someone put on the corner. Literally everything you need is on the treadmill. the two giant 3' rollers and a dc drive motor with speed control. Plus no need for pulleys/belts because your motor already has a pulley/belt that connects to the pulley/belt on the one roller. I even cut and welded the treadmill frame into the tumbler. Super easy.
 
I watched a YouTube video where a guy had 4 buckets on a tred mill, just laying on the belt, two rollers sticking up in the back to keep the buckets on the belt.
 
reference rpm. someone mentioned no more than 100 rpm. IMO that is too fast. we don't want the brass to get pressed against the drum, we want it to tumble.

when I was setting about to build mine I searched all over to see what speed commercial drums were turning (with limited success finding that info). then I tried to find the formula for calculating at what rpm the brass would be held stationary against the drum. I think I did find it, but encountered so many variables; drum size, mass, and so on.

someone else mentioned 30-70 rpm, and that is a pretty good target. my washer motor is two speed and that works for me. I also found some pulley size calculators on line.
 
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yeah, I was looking at pulley calculations last night, and since my motor is a 2 speed, I'm going to use a pulley combination that will put me where I can do below 50 and closer to 80 to see which works better.
 
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