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I'm currently working on trying to get a bright blue
Color on some parts of a post m 70. I at this point I'm getting a
Nice blue black color using stump remover and 500
Degrees on a propane stove. I just can't seem to reach
A bright blue. Is my heat to low or do I need something in
The nitre solution to reach the peacock blue? I'm also
Wondering if I use my casting furnace will it ruin it for casting
Lead if I don't get all the potassium nitrate out? Thanks for
Any help on this.
If you want a pre 64 finish on a post 64 gun. Rust blue it. But you will need to remove the post 64 finish. Ive done 1930s and 40s Win guns tyey turn out great when rust blued. Look lke a real Winchester should look.
Well thank you for your reply. I'm not really looking to copy
A pre 64 . I wanted to have the trigger, firing pin rear cap, safety selector,
And bolt release be a bright blue to contrast with the
Rust blue on the bolt handle,barrel and receiver.
Sorry if I wasn't being clear on what I'm trying to
Do.
Greetings,
My friend uses the Brownells Nitre Blue salts. It is temperature dependent as to the color you get. If you can rig up a PID controller to heat the salts you may get the results desired. Colors range from straw yellow to deep blue.
Cheers,
Dave
Set your lead pot to the proper temperature, and submerge the parts in lead. It works just like niter. The temperature is the important factor.
You need to get into the 700 to 750F range for that bright Spring Temper Blue color.
Some of it depends on what the steel alloy is, so some experimentation is also needed.
Sodium Nitrate was the commonly used 'salt' for the process. Winchester used to add a small amount of Manganese Dioxide to it. But that was to lower the melting point. These salts were used to temper parts at various levels and the Straw colors seen on some gun parts was often done with the mix.
You can use most anything that can be heated to those temps and the part can be submerged into it,,or even buried in it. The main thing is that the atmosphere does not get at the part while the color forms.
Some older gun companys like Ballard used to use clean dry sand with the parts packed tightly into the stuff as if to make a mould.
Some say wood ashes can be used as well but I've never tried it.
Molten lead will give you the results . You will need to wire each piece and hold them under the surface as they will want to float on the surface of the molten lead..
Temperature,,you have too be able to know what the temp is or what you want it to be.
You can't guess
A lead pot bullet casting thermometer works fine. Don't let the thing touch the pot , just the melted medium.
If you use Sodium Nitrate or Potassium Nitrate ( STump Killer),,and run it up to 830F you will get what looks like Charcoal Blue on small parts.
But don't let it get too close to 900F
At that point and beyond the steel will start to glow red and any color coating will be a dull grey only like a heat scale.
polish and start over.
Always let the parts cool on their own after treating
Hot water rinse will clear any of the dried salts.
DO NOT get water anywhere near any of these super heated compounds.
A drop of water in any of them will explode on contact and spray 700F hot salts or lead all over you. You can't get it off quick enough.
Eye protection a MUST.
Depending on how well you can control your heat, the bluing can be done with a torch. I blued the parts of this rifle using my oxy/acy torch.
https://castboolits.gunloads.com/sho...onal-Flintlock
Another plus for using the lead pot, niter will make everything in your shop rust!
Nitre blue is not a very wear resistant finish ..........the colour is controlled as mentioned by temperature and composition......sodium and potassium nitrate in varying proportions........however,someone not used to red hot industrial processes should be very wary........... also be aware that any organic material submerged in the melt may explode and shower red hot nitre everywhere.............when cold ,nitre is easily dissolved in hot water for cleanup........as mentioned ,no water near when hot.
Also be aware any hardened parts like hammer notches,sears ,triggers ,safety catch parts ,revolver cylinder bolts ,etc may be softened to the extent they wear rapidly.
+1 waksupi on the torch work and +1 with john.K on hardened parts. You can do a trigger with a torch IF you clamp a heat sink on the hardened area. Same for a hammer. 700 degrees is way too hot for any hardened part.
Sorry for not commenting for awhile got busy on projects.
Here is what I've learned. This is just from my limited experience.
You may have different experience. I tried the lead pot and yes it does
Work however I had lead stuck to the screws that had to be sanded
Off which also ruined the finish. Yes I could have reheated them but
That would have just caused further color change. In conclusion for me
At least it's easier just to buy pure potassium nitrate from a
fireworks supply and heat it up to I reached the color I wanted.
And yes it's not as durable but it is simple and fast to blue small parts.
YMMV. Hope this helps someone.