salt blueing

J

jollymon

Joined
Aug 20, 2009
Messages
4
what is the procedure on how to do salt blueing on damascus and what look does it give you. thanks
 
If you're talking about "hot blue" which is a very caustic salt and have never
done this before keep researching. The stuff I've got is oxynate #7 . At 285-290
degrees it will give you a deep blue black on mirror polished steel. It will also rust
the neighbors car in their garage. BE CAREFUL.
Ken.
 
Niter ( nitre) bluing salts are a potassium nitrate salt mix that melts around 400F. The blade is immersed into the molten salt and the surface colors to a blue. The temper is affected if the salts are heated above 500F. It works real well on fittings and such that are not hardened, and thus temper is not an issue. At 600F+ the color gets dark blue.
Stacy
 
I regularly hot blue using Oxynate #7, the fumes are caustic (er very bad for you). The hot salts will blind you if you are not carefull, if you get the salts on your footware it will eat through your shoes and if you get the steam on you from adding water to keep the temp correct you will itch all day and turn bright red.
Awesome stuff, wish I could mess with it more often.
Chris
 
The "backyard" method is to go to Lowe's and get Spectracide stump remover granules. It is the same potassium nitrate as the expensive stuff, and you can get a decent black around 400 deg, and for parts as you go up to around 750 it really turns blue, as in almost royal blue. I believe a bottle of the stuff is around $6. that is enough for small stuff for me.

http://www.spectracide.com/ProductCategories/BrushKiller/StumpRemover/
 
Gixxer,
What ratio do you mix with water? Any other things to know about mixing or using the Spectracide?

Thanks
Steve Hostetler
 
For all of you guys who are using Oxynate #7 and other caustic salts that are hazardous to use. There is a company supplying a bluing chemical that is a lot nicer to use. The company is Unibath. They must be building a new web site, but their contact information is here. http://unibathblueing.com/

It is called Unibath because it is a one tank bluing set up. You don’t have to have the metal sanitary before putting it into the tanks; this bluing chemical will remove light oils. So, no cleaning tanks. These chemicals do not cause rust on your machinery. The fumes are not (quite) as hazardous to breath and the steam from it has never given me caustic burns. I run the tank in my shop with just the door open to let in fresh air.

The chemical doesn’t go bad in a few months, like most so. I have had my tank set up for four years and have never had a problem with the chemical not working properly. The salts don’t crawl out of the tank as badly as most bluing chemicals do (it does a little). I have had much better luck with Unibath coloring difficult to blue gun parts than I had with O #7. The colors that I get from Unibath are a deep black. I mirror polish most everything before bluing and have had people ask me if my knife fittings were made of hematite.

The only thing is; Unibath is expensive. It cost me about $450 to set up a 36 X 6 inch tank. But, if you do much bluing and want easier to use chemicals that don’t rust your shop, this stuff is worth it.
 
SHostetler said:
Gixxer,
What ratio do you mix with water? Any other things to know about mixing or using the Spectracide?

Thanks
Steve Hostetler
Click to expand...

Not trying to be a smartass here but the last thing you want to do is mix water in something that you are cooking up to at least 400deg. I just take the plain jane crystals in a pan, and start cookin em over the side burner on my outdoor grill. Stuff melts eventually. going to Wal mart and getting a cherapo fry thermometer will let you know when you get to around 400 then you can start dipping. I have a pair of tongs that I use to place parts in, leave it there for a few min, you can see the progress, teh stuff melts clear, and remove. DO NOT splash this stuff on you, it ranks up there with molten low temp salts. MAJOR suck factor if it gets on ya.

Oh yea I forgot to mention that you do have to degrease before you dip.
 
I use sodium hydroxide to blue. 6# in a gallon of distilled water. This is caustic soda, a very strong base (opposite of acid). This mixture will boil at about 390 and give you a nice dark blue. I got it at Lowes from the drain cleaner selection. All drain cleaners are not pure sodium hydroxide. I use it in a medium size roaster pan and drilled a hole in the lid to stick a temperature probe in. I use it outside on a portable 2 burner propane stove. When it cools off it makes a nasty sludge. As with all this stuff use rubber gloves, goggles and don't get it on you or breath the fumes.
 
You must log in or register to reply here.
Back
Top