I am a trained scientist and have done much research on using electrolysis. Done wrong and it destroys coins. Done right it does absolutely NO damage to the metal surface of a coin. BUT -- it will usually remove any patina along with the other corrosion. Not a concern with badly encrusted coins, which defy soaking.
I use a battery or device charger as my electrical source.
The solution is DISTILLED water, with a small spoonful of sodium carbonate. ( Arm and Hammer washing soda). Do NOT use salt, sodium chloride, or baking soda.
The coin is held with a stainless steel clamp, which must contact the metal of the coin.
The other electrode is a carbon rod.
I use a battery or device charger as my electrical source.
The solution is DISTILLED water, with a small spoonful of sodium carbonate. ( Arm and Hammer washing soda). Do NOT use salt, sodium chloride, or baking soda.
The coin is held with a stainless steel clamp, which must contact the metal of the coin.
The other electrode is a carbon rod.