I do hundreds of chains a year, best solution I came up with, for me, is media blast ( aka sand blast cabinet) using crushed corn cob or walnut shells. If badly rustedor really gunked up I will toss it in the solvent tank and leave there until last , blast it off run it over a small round fixture to get all the links articulating again. Most of the traditional methods were to slow. I would never take a chain to a power wire brush that is just a disaster waiting to happen as listed above.
