coin cleaning

How To Build an Electrolysis Cleaner

Written by Bob Zito

I use this method but with Calcium Carbonate in the water for the electrolyte. It is recommended by salvage divers. They are trying to get the mineralization out of the object. It is what caused the corrosion in the first place. The few things I have to add are as follows:

1) Use Calcium Carbonate (Get cheaply at hot-tub/pool supply store)

2) Add in a ratio of 48:1 (water to calcium carbonate.)PH-11 is ideal

3) Adjust the current down to the point the fizzing slows down and then bring it up high enough to do the job. Any higher will just take metal away from the coin. Never go over 2 Amperes and try to stay under 1 Ampere (for small objects such as coins.)

4) Use a constant current power supply with current limit or circuit breaker/fuse protection on the DC secondary if available. 6-12 VDC will be fine for the electrolyte, 15-25 VDC may be necessary for the rinse. NEVER USE OVER 30 VDC! There will be a SHOCK HAZARD! Always use a transformer-isolated type power supply!

5) Use something to fix the distance RELIABLY between the Anode(+)& Cathode(-)or Coin to be cleaned. If they get closer the current will rise and your coin will lose metal! If they touch, the power supply will short which may damage the equipment or cause a fire.

4) Use distilled water or you may add minerals and impurities that ruin your coin. It's cheap! Or get some from your de-humidifier or rainwater is pretty good (unless you are in a very polluted area!)

5) Never leave a good coin alone with this method. You will be sorry sooner or later! Check it often! Practice first with cheap coins!

6) When done, you must rinse out the coin in clean distilled water then you MUST put new distilled water in a clean bowl and use a fresh Anode (+) Electrode and do it again WITHOUT the Electrolyte (Calcium Carbonate.)This step is essential to remove all traces of the electrolyte from the coin! You will have to turn the voltage up higher on your power supply just to get a little fizzing. This is normal as distilled water is not a great conductor. After adjusted for slight fizzing, you can let it sit for 7-12 hours (under supervision checks.)

7) Use a stainless steel fork, spoon for the anode and change/cut-off a new piece every time you change the solution. Don't try to reuse it!

8) You can do more than one coin at a time but you MUST NOT use the same solution with coins of different metals! Do not mix CLADS with Copper, silver or Nickel Nickel's!! If not sure do it separately!

9) Practice on your corroded Lincoln pennies, Rosey dimes, Jefferson Nickels and Wash. Quarters that are not VALUABLE! Age them yourself if you must in a salt or chlorine solution.

10) Protect your eyes and skin as the solution is caustic.

11) Use good ventilation as this process does produce fumes.

12) Use #16 wire to connect the Anode and Cathode. Use Flat grip=20 alligator clips or a plastic basket and wire wrap around the coin to grip it without leaving marks. Standard "sawtooth" alligator clips can damage the finish of your good coins. Try to put as little of the copper wire, alligator clip or other different metal in the solution as possible.

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