Home built gun bluing tanks?

I have made numerous tanks from both SS and black hot rolled 1/8" steel. Use the steel unless you can work thicker 1/8" SS. The thickness is required to maintain consistant temperature on smaller tanks when bluing numerous parts. Check out Brownell's online. Gunsmith supplies including complete tank setups.

John

The actual bluing salts tanks must be carbon steel. The cleaning and rinse tanks can be stainless. See

. They have a bluing instruction manual that tells you everything you would ever need to know. They also sell everything necessary to do a professional job. Brownells' major competitor is and also have everything you need.

Randy

You don't need to use thick steel for a blueing tank. The heat capacity of a tank made of 1/8 inch steel is low compared to the heat capacity of the solution. The thicker steel could be a help if you don't have a heater that will heat the tank uniformly. ie a long burner for heating a tank for rifle barrels.

Dan

||You don't need to use thick steel for a blueing tank. The heat ||capacity of a tank made of 1/8 inch steel is low compared to the heat ||capacity of the solution. The thicker steel could be a help if you ||don't have a heater that will heat the tank uniformly. ie a long ||burner for heating a tank for rifle barrels.

2 or 3 propane grill burners should handle that.

Texas Parts Guy

Thanks for all the input to everyone who replied.

Ray

Okay.....how do you keep the solution from "crawling" up the sides and out of the tank when not in use?

Scrape the residue from above the cooled solution on the insides of the tank and rub the cleaned walls with soapstone.

I once built a set of bluing tanks and used them. I got rid of that setup because that is one nasty process, very hazardous and it's difficult to dispose of the solution.

I built a 1" angle frame, 1" full length pipe burners with small holes every inch 45 deg either side of vertical, and 6"x6"x40" pans of tigged stainless, one for bluing, one for cleaning. (I don't remember the alloy, probably 304).

The rig worked as expected, with a deep black "blue". What's the issue with a stainless bluing tank?

Pete Keillor

"Peter T. Keillor III" wrote

You got that right, thats probably why a lot of smiths don't do it.

I'd be interested in dimensions for the burners. Like geometry of the mixers, orfice size, Nat gas or propane, size of holes in burner pipes etc. I'll soon be in legit business building and repairing guns and am considering setting up a bluing operation.

Brownells recomends an iron tank for thier salts. SS is said to leave little silver specks in the finish. I'll take thier recommendations. We used Brownells salts in gunsmith school and those tanks were iron also. They also cost much less. Tom

See

Hmmm. Never noticed any specs.

Tom, I'll do my best, but it was over 25 years ago. I used the orifices for unvented room heaters like the old Dearborn. These were mounted in bell reducers similar to a Reil burner, but mounted coaxially. The burners were as long as the tanks, and I just drilled small holes about 1/8",(don't remember exactly, but was trying to emulate the room heater burners in a more favorable geometry.)

I made two rows of holes spaced about 1" apart down the pipe and 45 deg either side of vertical. The ends were just capped. I made sheet metal dampers with the pie slice air holes which fit over the bells. I don't remember what I did to mount the orifices coaxially, but what ever it was had to have been made with a hacksaw and drill press. I had no machine tools until recently.

It didn't take a lot of gas pressure. I used a standard weed burner / gas grill type regulator and a needle valve. You're only trying to boil water, not run a foundry.

If you do this, Brownell's ought to be able to advise you with more current information and much more experience. If it were me, I'd figure out how I could legally dispose of the waste before considering embarking on this adventure.

After reading the ingredients (caustic soda, sodium nitrite, sodium nitrate -- extremely alkaline and strongly oxidizing), I did the bluing in chemical goggles, chemical slicker suit, rubber gloves, face shield, rubber boots, the whole nine yards. By far the most hazardous procedure was adding the water back to the bath to keep the temperature at 295 deg F. As the water in the solution evaporates, the temperature climbs. The water must be replaced or you'll get an off-color purplish finish. The water you're adding boils at 212 of course, so lots of flashing and spattering can (make that will) happen.

I found the best approach to lower the ladle with the water into the surface of the bath, and then slowly draw the ladle along the surface to entrain the water into the solution. What ever you do, don't submerge a bunch of water, or you'll get a steam explosion.

Good luck.

Pete Keillor

Brownells also sells the chemicals and a pH tester to neutralize the bluing salts so that they can be flushed down a sanitary sewer. Some gunsmiths add water safely by putting ice cubes into the hot salts solution.

Randy

Brownell is overpriced!