I'm going by memory here, but I believe these are the steps:

Get a tub of DAP Oxalic Acid crystals - can be purchased at Sherwin Williams,
Mix a couple of tablespoons of it per gallon of water or so (this might be overdoing it, for that matter),
Dunk objects for a few hours,
Remove and rinse with water and baking soda,
Let dry.

-Kurt