I am attempting to do some gun bluing in my shop on a project that I am finishing up and would like to find out the details of actually setting things up, recipes for the gun bluing itself, and the how-to's of it as well. I have done hot gun bluing before at a technical college, and managed to talk to the instructor at length about the techniques involved, but didn't get enough information about the other things. If anyone has any info at all about the process, etc., it would be greatly appreciated.
I've done more gun bluing that I care to remember. Just recently sold my small bluing shop's equipment because I just got tired of doing gun repairs and refinishing. The first thing you need to remember is that the caustic salts are HOT, 290 degrees or so. Add water to the tank and the water will explode into steam and bath you in the hot caustic salts. Gotta have the right tecnique of adding water to stay out of the hospital. Proper PPE is a MUST! Second thing is that corrosive caustic fumes/vapors will be everywhere and will start eating anything that is steel closeby. Adding anything that is aluminum to your bath will either ruin the bath or dissappear all together Third is everything has to be squeaky clean. Special hot cleaners, 190 deg or so< are needed to remove traces of oil and grease before anything goes in the bluing tank. Forth is disposing of the bath when your done. You cannot just go dupm the caustic salts in your back yard or flush it down the drain to dispose of. It is high PH and must be disposed of properly
All in all, I'd suggest you find someone with a gun bluing operation nearby to do your bluing but if you cannot, then the equipment needed can be made and supplies be purchases from Brownells. Good luck.
Have a look at "Firearm Bluing and Browning" by Angier. Any decent library should have a copy or can get it. Hot salts bluing isn't a process that you set up for a onesie-twosie run, it involves really nasty hot caustic solutions that can maim and, these days, the used salts are considered toxic waste. Brownell's sells the salts and equipment and the stuff needed for proper neutralization if you're setting up for business. As an alternative, take a look at either Dicropan or the old Herter's "Belgian Bluing". Neither involves much more than a tank of boiling water and some hand work. I've used the Herter's method, you can do a rifle action in an afternoon and you end up with a real blue job, not black, quite durable. Just takes more work with carding off residue. Angier lists it under "Hot Water Method", IIRC. Also good for soft-soldered double shotguns. Another alternative is to find somebody with the tanks already, do your polish and prep and haul it to them for the final dunk. The real work is in the prep.
If you're expecting to make your own salts, some of the chemicals involved and the amounts needed may get you more legal attention than you want these days if you're an individual. If you're setting up in business, it's different. They are also HazMat if you live in the sticks and have to use the big brown buggy for delivery. Figure at least $20-25 extra per package.
Brownell's Gunsmith Kinks series of books has a lot of hints on bluing, discounts on same if you buy one of their catalogs.
Three is an excellent treatise on this on (I think) the Roderus forum. Involves a turkey cooker, lye, and some other common ingredient. Looked pretty good to me.
Try Brownells.com, they offer equipment and chemicals. Also some damn good manuals. If you've seen it in school, you know it's not practical for a one- time operation.
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