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Snow ninja
04-04-2017, 11:58 PM
Working on a 1911 build and during the many hours of filing and lapping, some thoughts pop into my head. The gun I'm making will be a two tone and I'm planning on keeping it that way, but...

The frame I bought is a Para Expert frame that is, according to the website, carbon steel with a Nitride finish, it is apparently a clear finish, as the gun still looks in the white.

My hypothetical question is, could this be blued? I'm not familiar with Nitride, and wasn't sure exactly how it adheres to the metal. And if you were to blue it, what would you have to do to prep the metal?

Thanks, -Matt

David2011
04-07-2017, 05:31 PM
All the nitrided parts I've seen either had a bronze tint or a very few were black, probably by an additional process. Look up nitrided drill bits. Nitrided steel is extremely hard. It's not a finish like plating. It becomes a molecular part of the base metal. If a stone, sandpaper or file will leave a mark or cut the metal then it's not likely that it's nitrided.

I tried to to hone a nitrided model airplane engine cylinder once with a brake cylinder hone. The hone just skidded across the cylinder with not a scratch to be seen.

JSnover
04-07-2017, 06:00 PM
All the nitrided parts I've seen either had a bronze tint or a very few were black, probably by an additional process. Look up nitrided drill bits. Nitrided steel is extremely hard. It's not a finish like plating. It becomes a molecular part of the base metal. If a stone, sandpaper or file will leave a mark or cut the metal then it's not likely that it's nitrided.

I tried to to hone a nitrided model airplane engine cylinder once with a brake cylinder hone. The hone just skidded across the cylinder with not a scratch to be seen.
All of the above. I worked in a tubing shop with nitrided dies and the surface hardness was unbelievable. Your bluing process might discolor it but that coating isn't steel and won't respond the way you want it to.

ulav8r
04-07-2017, 06:17 PM
Have only had experience with one type of nitriding, the melonite process. It was being used to harden the surface of electric motor shafts. We centerless ground them and then sent the shafts out for hardening, then polished them when they came back. After polishing, they were bright black and would look good on gun parts. Size variance from before treatment to after polishing was no more than .0002, usually less. The surface hardness was 76-80 Rc.

Snow ninja
04-07-2017, 08:01 PM
http://www.e-sarcoinc.com/para-expert-1911-frame.aspx
This is representative of the one I ordered, see description...
192773
And this is mine... You can kind of see a difference in finish near the top grip screw hole. Makes me think that maybe "nitride" isn't the right word. Now that you mention it, I have seen parts with the bronze tint, and this gun is definitely not that. I'm thinking Sarco just got their description wrong. Thanks for the help guys.