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Neutralizing hot bluing solutions

2003

What is recommended for neutralizing the hot blue salts (sodium hydroxide / ammonium nitrate) on steel to prevent further rusting after it has been blued in a hot tank?
Do I need to rinse using boiling or hot water? I have the necessary equipment to perform the hot / blue process.

I am aware of the dangers and have the proper safety equipment for handling the solution.

Kip McClary
- Whiteville, North Carolina, USA

Kip, after removing from the bluing tank, you need to put the items in a fresh water rinsing tank for a couple of minutes. Don't leave anything in the rinse tank for over a few minutes. The fresh blued metal will pick up oxygen from the rinse water if you leave it in too long and will show grey specks after a few weeks (this is rust forming).

Scrub the metal with a soft brush and cold water, rinse with hot water, let dry and apply a good light weight oil. There are some special solutions made to prevent "bleed out" of any bluing salts in any joints from pieces you couldn't separate. Search "gunsmithing supplies" and you will find a lot more information.

Good luck, be careful.

Ed Kay
- St. Louis, Missouri, USA
2003