Well, the board is either fixed, or it's going to run terribly. Cross your fingers and hope for the best. I'm at my technical limit right now.

Oil Blackening (bluing) screws?

Post Reply
Message
Author
Tommy Atkins
Global Moderator
Global Moderator
Posts: 205
Joined: Sat Jun 03, 2017 4:47 pm
Age: 66
Location: Hagerstown, MD
Canada

Oil Blackening (bluing) screws?

#1 Post by Tommy Atkins » Fri Aug 25, 2017 5:28 pm

I find the need to oil blacken several screws, none really large.
As this is my first attempt I went online looking for info & found a bewildering set of temperature variations. They vary from "heating till the metal turns the shade of blue you want" to "red hot", & everything in between! It strikes me that red hot is going to change the hardness & temper of the screws, so whats the real story to blue with heat & oil? Do I heat, blacken, harden then temper or what?
I'm also being put off old motor oil for several reasons, but can easily use Linseed as I have plenty of it.
I have both a dedicated toaster oven & a propane torch for heat, which is gong to serve me better (assuming It will reach & sustain the temp I need)?

User avatar
Rapidrob
Global Moderator
Global Moderator
Posts: 334
Joined: Sat Jun 03, 2017 9:10 am
Age: 66
Location: New Mexico
United States of America

Re: Oil Blackening (bluing) screws?

#2 Post by Rapidrob » Fri Aug 25, 2017 7:30 pm

Heat to dull red,dunk in motor oil. It will be black. I do it all the time. It will not take the temper out of the screw.
Tin Can Sailor
'Nam Vet
NRA Endowment Member
President New Mexico Military Surplus Rifle Pistol Shooters

Tommy Atkins
Global Moderator
Global Moderator
Posts: 205
Joined: Sat Jun 03, 2017 4:47 pm
Age: 66
Location: Hagerstown, MD
Canada

Re: Oil Blackening (bluing) screws?

#3 Post by Tommy Atkins » Sat Aug 26, 2017 4:41 pm

Thanks, Rob. Someone else suggested Linseed, which I have, any thoughts on one Vs the other?

User avatar
Rapidrob
Global Moderator
Global Moderator
Posts: 334
Joined: Sat Jun 03, 2017 9:10 am
Age: 66
Location: New Mexico
United States of America

Re: Oil Blackening (bluing) screws?

#4 Post by Rapidrob » Mon Aug 28, 2017 9:55 am

Just about any oil will work.When in doubt,try a scrap screw first.
Tin Can Sailor
'Nam Vet
NRA Endowment Member
President New Mexico Military Surplus Rifle Pistol Shooters

bobvz
Junior Member
Junior Member
Posts: 40
Joined: Mon Jun 05, 2017 8:50 pm
Location: USA, SC
United States of America

Re: Oil Blackening (bluing) screws?

#5 Post by bobvz » Thu Aug 31, 2017 9:16 pm

Linseed oil is fine. Yes practice on a few screw heads and you will get the technique down. Do the heating in reduced light so you can visualize the colors. On screws heat the shaft just below the screw head and let the heat migrate into the head. You can control the color better that way.

Post Reply

Return to “General Gunsmithing”

Who is online

Users browsing this forum: No registered users and 1 guest