Zinc plating is an electrochemical process by which zinc ions in an aqueous solution transfer to the surface of another metal because of changes in the metal's magnetic state. The process depends on electrical stimulation of the solution, which excites the zinc ions free from their chemical bond to the water and onto the cathode metal suspended in the solution. An inexpensive DIY zinc plating process will produce a dull finish that will protect steel from rust but won't have the same lustre as chrome or stainless steel.
Prepare an etching bath by mixing 2 gallons of water and 2 gallons of muriatic acid in a 5-gallon bucket.
Fill two different buckets with 4 gallons of distilled water.
Prepare an electroplating bath by pouring 4 gallons of distilled water, and then stirring in 227gr of zinc oxide powder and 1361gr of sodium hydroxide (NaOH).
Collect the parts to be plated and thoroughly clean them with an abrasive pad and soap and water. Suspend each piece from a 1-foot length of copper wire.
Wrap the loose ends of the suspension wire around the copper tubing and allow the pieces to dangle in the etching bath for about four or five minutes. If necessary, additional pieces can be suspended from the edge of the bucket.
Transfer the pieces to the rinsing bath of distilled water and suspend in the water for about 30 seconds. Swish oddly-shaped pieces around to ensure that all of the muriatic acid has rinsed off.
Suspend the copper tubing over the plating bath and hang all of the pieces from the tube into the bath.
Connect the negative lead from the 12-volt power supply to one end of the copper tubing. Connect the positive lead to the zinc anode and submerge the anode in the plating bath.
Turn on the power supply and allow the plating to bubble between 30 seconds and two minutes, depending on the thickness of the plating desired.
Transfer the plated pieces to the rinsing bath, and then lay on plywood or shop towels to dry.
Conduct the plating in a well-ventilated area, as the fumes can be noxious.