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View Full Version : Black Oxide Finish



jmcmullan
11-04-2004, 11:16 AM
Anyone have any recent experience with using any of the room temperature Black Oxide finishing processes? Specifically I'm looking at one of the Caswell kits (http://www.caswellplating.com/kits/black.htm) and was wondering how well the finish holds up. On some older postings this seemed to be somewhat of an issue, but no one mentioned the Caswell products which seem to have pretty good user reviews. Sure would be nice to give a pro finish to some of the fixtures and tooling after putting all the machining effort into them.

Rustybolt
11-04-2004, 12:17 PM
Not really comparable to a professional black oxide finish. It does an OK job if you're not too picky. Make sure your parts are clean and oil free and it doesn't hurt to warm them up a little.

GreenWillyPeter
11-04-2004, 02:32 PM
Brownells, www.brownells.com, (http://www.brownells.com,) gunsmithing supplies has two parkerizing systems, manganese and zinc phosphate, several "cold blue" products like 44/40, Oxpho-blue, Dicropan T-4, Aluminum black,etc., I've used most of them at one time or another with different degrees of success.

Also some epoxy, spray-on, bake-on products. Some of the gunsmithing forums have input on the spray products.

Some must be heated but you can use a coffee can for small parts or torch for larger pieces.

"Cold bluing" has good results and will last a fair amount of time, but not as good as "Hot Bluing". Warm the parts up in boiling water to clean off the oil and help with the depositing.

The phosphates can be obtained at several online chemical supply houses a 20% to 50% cheaper than Brownells.

Contact your local gunsmith to see when he is making a bluing run and maybe work out a deal.

Copper sulphate and gun blue work great for layout work.