Cleaning spendable coins

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But by that rationale you could buy your coffee with nice freshly salt water cleaned cash - no need for damn telephones and their finger print time wasting desires
 
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Based on others suggestions I made a mini tumbler from some scrap PVC parts and an old low speed geared motor. It runs off an old wall wart power supply.

Others have suggested using "Jewelers mix" tumbling medium - I tried some surplus M3 or M4 x10 stainless countersunk screws. They seem to work well.
I just add 50ml or so of CLR and a drop of dish washing liquid. Some are clean in 30 minutes some in about 2 hours.

Coin Tumbler (3).jpg

Coin Tumbler (1).jpg





Coin Tumbler (5).jpg
 
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Hi lux,

That is an interesting simple design, you could use the drive motor off of one of those 12Vdc kiddie cars usually thrown out onto the footpath, and a "wall wart".

I noticed you sealed the drive bolt with silicon and smeared the silicon around the inside wall of the tube too, did you do that to provide a bit of grip to tumble the media and objects ?
I will silicon a few small paddles on the internal sides to make the coins travel up then drop against each other.
A person could use an old cheap cordless 12Vdc drill (or other voltage) where the battery pack is too expensive to replace.
Or even an old speed controlled cheap 240Vac drill, lots of possibilities for a drive motor.

Maybe a handful of fish tank gravel, smashed quartz gravel, granite gravel - something hard with edges but small sized. FREE.
Some 1/4 teaspoon citric acid and 1/4 teaspoon dish liquid, some warm water to cover the coins - don't leave the coins in the water too long, citric acid will remove the nickle and start to eat the copper after 24hrs.

NOW I have to go and build one!! :rolleyes:
Pictures soon.

Missed out on my second kerbside treadmill last night, damn it !
Looking to turn one into a rock tumbler, quiet to run, speed controlled and best of all FREE.
The kids are still wanting to tumble rocks from EVERYWHERE they find them. (God help me)
I will put that one up on DIY when it happens.
 
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That is an interesting simple design, you could use the drive motor off of one of those 12Vdc kiddie cars usually thrown out onto the footpath, and a "wall wart".

I noticed you sealed the drive bolt with silicon and smeared the silicon around the inside wall of the tube too, did you do that to provide a bit of grip to tumble the media and objects ?
I will silicon a few small paddles on the internal sides to make the coins travel up then drop against each other.
A person could use an old cheap cordless 12Vdc drill (or other voltage) where the battery pack is too expensive to replace.
Or even an old speed controlled cheap 240Vac drill, lots of possibilities for a drive motor.

Maybe a handful of fish tank gravel, smashed quartz gravel, granite gravel - something hard with edges but small sized. FREE.
Some 1/4 teaspoon citric acid and 1/4 teaspoon dish liquid, some warm water to cover the coins - don't leave the coins in the water too long, citric acid will remove the nickle and start to eat the copper after 24hrs.

NOW I have to go and build one!! :rolleyes:
Pictures soon.

Missed out on my second kerbside treadmill last night, damn it !
Looking to turn one into a rock tumbler, quiet to run, speed controlled and best of all FREE.
The kids are still wanting to tumble rocks from EVERYWHERE they find them. (God help me)
I will put that one up on DIY when it happens.

It was a bit of a guess and try design. I had it at about 45° and noticed some larger coins would spend a few rotations skidding on the back fall before tumbling. Dropping the angle down to about 30° fixed this. The silicone around the wall seems to help the coins climb the wall then tumble.

The old cordless drill is a great idea - I might look at that as I have one sitting around.

I found some very very corroded copper pennies and half pennies yesterday and tumbled them - I think the stainless screws as tumbling media might be a bit harsh for tumbling any 'keeper' coins. I might try using just a handful of M3 or M4 stainless nuts. They don't have the sharp pointy bits that the screws have.

I used neat CLR as the liquid, I wonder if something like vinegar might do the job.


If you are going to make one with the PVC tube to tumble rocks it might need lining or thickening up. On other jobs I've cut a slit out of the PVC pipe lengthwise and then glued it inside outer pipe to thicken up the wall. Maybe that might work.


Gotta go find some more coins to play with!
 
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Yeah just solder a connection, or the wires of the 'wall wart' to the drill battery contacts.
I made a 12VDc drill for camping, just connect to the car battery.

I don't recommend using vinegar, it loves to eat copper and zinc, so your copper and brass coins will be ruined quick smart.
Citric acid is only a few dollars and at the supermarket, lemon juice is high in citric acid. Denture tablets may do it (have not tested them yet)
The smaller the stainless media and the greater the number, the better, less weight but more surface contact friction. eg fine fish tank gravel

The rock tumbler being based upon the treadmill will use an end of life extra wide race car tyre with a bar horizontally through the top center opening having an outer sleeve as a roller to make sure the thing don't fall off the treadmill. Just stand it vertically on the rubber tread mat, then add water, rocks, some hard grit and a few short bars of 10 and 12mm reo, maybe some bigger rocks into the inside of the tire. No paddles because you want them to slide and roll and the tyre inner is rubber.
Quiet, speed adjustable and almost totally $free$.

Got to find that treadmill.
 
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I cleaned up a couple of old, worn predecimal silvers the other day. Soaked them in lemon juice over night. Washed them in water and then rubbed them with bicarb until clean. They were in poor shape but came up very clean at the end of the exercise.
 
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