Home parkerizing came up in a thread last week about "protecting a threaded part". As promised, here's a short review and publisher info of a booklet I have on the topic.
Home Workshop Parkerizing By Blaze C. Barrymore Publisher: Butokukai, Cornville AZ 86325 My copy came from G.S. Sales, PO Box 207, Antigo WI 54409, (715) 623-3185. The area code may have changed...
The book breaks the process down into dissasembly, degreasing, removal of finish, parkerizing, and oiling. The process is logically described, with adequate attention given to the options provided at each step. The "removal of current finish" section is probably the most complicated, discussing sandblasting, beadblasting, or acid removal of existing surface. The section on Parkerizing itself is good, but the ratio of 1:5 of phosphoric acid to water, doesn't specify what concentration of acid they're starting with, and doesn't have the warnings you'd expect about always adding acid to water rather than adding water to acid.
The process itself looks pretty simple - degrease the part, make the surface ready for parkerizing, boil it in the solution until it's the right color, and oil it while it's hot. The 28 page booklet has enough detail to give a bit more comfort to the process, but I'll do some scrap pieces before I try it on anything important. Probably worth the 10 bucks I paid for it.
Dave Hinz