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Love Life
11-30-2019, 01:41 PM
I plan to checker the backstrap of one of my SAA clones. Instead of cold or hot salt bluing, I am considering Nitre bluing the grip frame. I know that the temperature from nitre bluing will ruin the heat treatment of the grip frame, but does that matter? They make brass grip frames, which one can only assume is probably more soft than the steel grip frame would be, and the brass grip fames last just fine.

What do you think? Is this a safe route or should I stick to a hot salt or cold blue?

M-Tecs
11-30-2019, 01:48 PM
I would be surprised if the backstrap material is heat treated. My guess is it's a low carbon steel so Nitre bluing temps will not adversely affect it.

Love Life
11-30-2019, 01:55 PM
What do you think would be a good quenching oil? For a part like this would you recommend a fast or slow quench oil?

M-Tecs
11-30-2019, 02:25 PM
While I do have extensive heat treating experience I have never personally done Nitre bluing. Per the manufacture they recommend water.

https://www.brownells.com/userdocs/learn/Inst-362%20Nitre%20Bluing%20Bluing.pdf

Quenching is just rapid cooling, however, for heat treatment quenching does very little until the material coverts from ferrite to austenite. With most steels this is between 1,3500 and 1,600 degrees F. With the Nitre bluing temps of around 600 degree your can remove temper from some materials but quenching at that temperate will not make the steel harder reguardless of carbon content.

M-Tecs
11-30-2019, 07:38 PM
Just food for thought. Checkering a backstrap on a SA may not be the greatest idea. In the 70's I had a set of SA grips that was checkered on the backstrap. It was a 45 Colt but in a Blackhawk. With heavier loads the checkering would take the skin of my hand. With light loads it changed how it rolled. I don't know if this could be inserted as a trial before you cut metal. https://www.brownells.com/handgun-parts/frame-parts/frame-hardware/front-straps/blued-front-strap-sku965100001-16409-36879.aspx

john.k
11-30-2019, 08:03 PM
My experience of nitre bluing ,or any other heat oxidation,its very thin,and wears away quite rapidly if the gun is handled........but lovely colours for a glass case piece.

Jeff Michel
11-30-2019, 09:19 PM
Best with screw heads and dome topped pins, small things. it isn't a coating, it's a oxidation of the surface as such it's very difficult to control the temperature to get a consist color. Thin sections will be a peacock blue and thicker sections will end up straw or brown. Hold it too long you it's a mottled black Surface finish is everything, the smallest scratches show up like a neon sign. I use vegetable oil as a quench. You might consider running some practice pieces to get a feel for the job and to have an idea if warping will be a problem. Good luck with your project.

Love Life
11-30-2019, 11:03 PM
All stuff to consider. I’ve been Nitre bluing small parts for the last 3 years, but nothing this big. It’s a pretty finish.

I may just send it off to be dunked in a hot salt tank.

M-Techs: I’ve heard that about a checkered backstrap on the SAA. I’ve also seen checkered back straps so it’s something I want to try out for myself.

john.k
12-01-2019, 09:16 PM
If the piece has any weld filled holes ,these can turn out all sorts of colours ,bright pink blending into green is my favorite......The colours are of course light refracted by the thin layer of oxide ,for the most spectacular blue by this effect try titanium sheet......brilliant sky blue just from heating in air.

Geezer in NH
12-03-2019, 08:12 PM
I would rust blue it.

jaguarxk120
12-04-2019, 11:32 AM
Remember nitre blue is very delicate and what ever parts you blue should be coated with
a varnish or poly coating just like case colors.