Picture
Cleaning modern coins to make them "spendable" again is best done with a rock tumbler.  Water, soap, gravel and coins go in for a few hours and come out presentable enough to be acceptable.  Harbor Freight offers an inexpensive and effective rock tumbler that works well, provided you take some common-sense care in using it.  The weak point in the design of this tumbler is the belt, but following these tips below will help your tumbler run better and your motor and belt last longer.

The original belt should last quite a while if it is adjusted properly and you are not overloading the tumbler.  In a pinch "standard" size 1/4" wide rubber bands work as belts too, but long term use of them can damage the plastic pulleys.

Make sure you adjust the spacing of the two pulleys (yes, this is adjustable) to be just enough that the belt is not too loose (i.e. it just catches).  This keeps the belt at the right tension and not too tight.  If it is too tight it will work, but it will stress the belt.

Don't overload the tumbler.  It is rated for 3#.  If you are filling it to the brim with coins, rocks and water it is too full and too heavy.  This stresses the motor and the belt.  Ideally the tumbler should be no more than 1/2 full of rocks and coins and no more than 3/4 full when you add water.  Besides saving the motor and the belt life, a properly loaded (not overloaded) tumbler works better and faster at cleaning your coins as the material has room to move around in the drum.

Replacement belts can be located cheaply on eBay and are typically as good or better than the original belt.  Many rock shops and lapidary stores sell them in retail stores and online too.

 


Comments

Ringfinder

Wed, 03 Feb 2010 17:46:07

You can buy the belt for the tumbler at Harbor Frieght for around $2.

Nick is right, loosen the belt tensioner, your belt and motor will last much longer.

This winter I have cleaned over 4,000 clad coins with my double tumbler.

 



Leave a Reply