How to Etch Stainless Steel With Acid
Stainless steel can be etched using ferric chloride mixed with water, which creates a hydrochloric acid. The acid will slowly eat away layers of the metal, and it will flake off leaving exposed areas that create a design. A resist is applied to the metal, then the metal is dipped into the acid until the desired effect is achieved. This process is quick and easy to repeat for other designs once you have learned the technique.
Sand the stainless steel gently using fine steel wool. It needs to be gritty enough for the resist to stick, but not visibly scratched. Rinse the steel in plain water, and wipe with isopropyl alcohol. Lay the steel aside.
Print your design on heat transfer paper using an ink jet printer. Heat an iron to its hottest setting. Place the heat transfer paper face down on the steel, and iron it for two to three minutes. Carefully peel the transfer paper backing from the steel, leaving the design on the metal.
Put on rubber gloves and goggles. Pour water into a large, flat glass tub and mix at with ferric chloride at a one-to-one ratio. Pour the acid slowly into the water, not water into the acid. This will prevent dangerous chemical reactions.
Dip the stainless steel face down into the acid. You will see metal flakes begin to fall away from the plate. Allow it to soak for several minutes. Remove and rinse with water. If you are not happy with the results, allow it to dry completely before re-dipping.
Wipe the stainless steel with isopropyl alcohol to remove the resist.