Cleaning steel parts to prepare for cold-blue

[gunsmither]

I decided to keep this thread alive rather than beginning again.
I bought Oxpho blue from Brownell’s.
Unfortunately I wasn’t paying attention and got the, “Creme” formula.
I’ve never used it, I’m not impressed with it but I have two bottles and will learn to love it!

I cleaned the part with acetone. I then made sure it was dry, applied plenty of blue. Let it sit for five minute, rinsed in warm water then repeated the process. I didn’t notice any difference after the second application.

Is there a better bluing product? Is there a better and cheaper product?

Thanks guys.

I suggest you try the ScotchBrite, as I mentioned earlier. It blends the chemical in much nicer in my experience.

 

[Janderso]

I suggest you try the ScotchBrite, as I mentioned earlier. It blends the chemical in much nicer in my experience.

Ah, i guess I didn’t read carefully.
I have plenty more to blue after heat treat and surface grinding.
The pics don’t show the light coloring and a bit of splotchy inconsistencies.
I’ll give the scotch brite a try.
Thanks man.

 

[mickri]

You might want to try this stuff. https://www.rustblue.com/ I have some bluing projects on some of my firearms and plan to give this a try. Lots of positive comments on the Accurate Reloading gunsmithing forum.

 

[ChazzC]

I’ve tried Birchwood Casey and Van’s, even using the recommended Old Devil degreaser from Frontier Products with the Van’s: all of the cold blues give about the same results.

The best results:

• Clean the part with 90% Isopropyl Alcohol, followed by Acetone, wearing gloves to prevent skin oils from messing things up.
• Warm the part to about 120F.
• Daub the cold blue (from a clean, separate container - you’ll contaminate the whole container of blue otherwise), rubbing the solution into the surface.
• Let the part sit for 10 minutes, then apply again.
• Rinse the part with hot water, then soapy hot water, rinse and dry.
• Coat the part with light oil (I use Craftsman Light Machine Oil since I have a quart can) and let it sit overnight.
• Wipe the excess oil off the part with a clean cloth or non-woven HD paper towel.

Several write-ups in Gunsmith Kinks mention rubbing the blueing in with clean steel wool (steel wool soaked in solvent to remove any oils), but haven’t tried this. @gunsmither suggestion of using ScotchBrite would be similar.

Good luck!

 

[GeneT45]

I like to boil the parts after degreasing with acetone. The boiling is the final degrease and heats the part. Remove the part and the latent heat will evaporate the water. As ChazzC mentioned, the heat is a critical component to a good 'cold' blue. I slather the part liberally, then let them sit for *at least* 10 minutes. You can repeat this several times to get a darker part - when it's as dark as you'd like, or not getting darker, proceed...

Then I wipe off most of the blue and drop the part in oil. Used motor oil is fine, maybe even better. Let it soak for a bit then take it out and wipe it down.

If you're willing to consider changing horses mid-stream might I suggest parkerizing? Parkerizing provides better corrosion resistance and holds oil better than black oxide (bluing). Scotch brite or carding wheels are for obtaining a high sheen like you might want if you were re-bluing a firearm (or trying to imitate a Starrett finish). If that's what you want, a carding wheel is a worthy investment.

GsT

 

[gerritv]

I use Caswell black oxide. https://caswellplating.com/black-oxide-kits.html I mixed up some from the concentrate, keep it in a glass jar with sealed lid. Have blackened many parts without refreshing the mixture. I do the usual cleaning, sometmes inclduing glass bead blasting. Dip into mixture for 3-4 minutes, rinse thoroughly with distilled water and then oil.

Gerrit

 

[aliva]

I did a small unscientific test on a couple of bluing compounds

Black Oxide Test

I decide to do a test comparing 2 different black oxide treatments I'll compare Brownells Oxpho-Blue to Caswell Plating's cold black oxide concentrate. Product: Brownells Oxpho-Blue 4 oz. U.S. Cost from Amazon $34.54 $8.58/ U.S .oz. (taxes and shipping extra) Caswell Plating Black Oxide...

www.hobby-machinist.com

 

[DeadGuyAle]

Messed with cold bluing to patch small parts with existing blue. Results are acceptable on these but never had much success with larger than a dime size on a flat surface.
As said above heat, polish and multiple coats.
Let us how it goes, have a fair amount of cold bluing coming up!

steve

 

[Shotgun]

I bought some cold blue solution, but have never used it. I got lazy with the parts I bought the blue for and instead put them in my shop toaster oven at 450 for an hour or so, then dumped them in a bowl of used motor oil.
After cooling, they don't come out black. More of a bronze to blue color. But, they don't rust, and the "coating" seems to be really resilient. It was so easy and successful that I haven't bothered with the bluing.