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Chemical Process to Brown Auto Parts and Springs

Brown process by chemicals

We are looking simple process of brown finish chemical coating to auto parts & springs please advise formula & process

Faqir Mohammed Malik
Auto parts manufacturer - Karachi.Pakistan
March 10, 2009

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April 11, 2009

Not sure why you want to do this as browning entails creating rust, but you asked! There are 100 and 1 different ways to do it. There are commercial products that work -- sort of! And there are non commercial products that work -- sort of! The old world gunmakers used to use urine. Heat the part to about 100 degrees Fahrenheit and paint the urine on. Let the part rust. Card and repeat. Sal Ammoniac .


can be used in exactly the same manner.

Clorox bleach ⇦ bleach/sodium hypochlorite in bulk on eBay or Amazon [affil links] is also used in the same manner. The best I have found is iodine mixed with ethyl alcohol. It is done the same way but gives a slightly shinier finish. A finish not unlike that of a new penny. For what it is worth the commercial made solutions are applied the same way. It can take up to 30 coats to give a nice even brown finish. The finish must be protected with oil or wax or it will continue to rust and cause pitting. I have tried all of the above except urine and the results are all very close to the same. All of the chemicals I have listed are dirt cheap but the labor and frustration will drive you nuts! There is something to be said for brown paint or powder coating. ;o) Rod

Rod Henrickson
- Edmonton Alberta Canada