I recently completed some rust bluing on a couple Mauser based bolt rifles. I’ve posted here and other forums, talked to several people, and have yet to find the root of my problem. The issue is getting a good black color. I consistently get a gray color, in addition to a tough reddish rust post boiling. Each cycle gets worse to the point I can’t card effectively and sometimes end up starting over. Other parts do fine, and sometimes all parts blue up nicely. Barrels seem to be the most trouble, with low carbon softer steels reacting favorably. Recently I blued one complete barreled action with no issues. The second barrel gave me fits. It was etched enough I had to re-file and polish it out a second time. The rust was tough enough my usual #4 double cut file didn’t want to cut through it.

Obviously I’ve tried everything, plus changing all the variables, independently, over time. In desperation I added about a tsp of muriatic acid to the boiling water. The barrel came out of the water blacker than the ace of spades, the rust carded perfectly and the final finish was excellent. I was tempted to add some soda ash at first, but ran across some info in Angiers book that specifically mentioned soda ash and boiling water causing red rust. So, I figured I’d do the opposite……I know the change in water was the difference because the untreated surfaces, i.e. barrel tenon, turned dark as well. Not rusty, just dark vs bright metal. The bright surfaces normally stay bright through most if not all the cycles.

I’m posting this to hopefully find help in understanding what is happening, and of course, help other people down the road. Will also be testing again with a scrap barrel and will update.

What chemicals are you using to rust blue with? How do you polish your metal? What is your process procedure? What is the source of the water you are boiling with?

Have used Mark Lees & Gun Goddess. Water from 2 different dehumidifier’s or store bought distilled water. Draw file and polish by hand anywhere from 240-400

You’re not the only one…in the last two years I have had a hell of a time with rust bluing. It used to not be the case. I don’t know what has changed, and like you I’ve altered certain parts of the process thoughtfully to test where the issue might be. Nothing.

My experience mirrors yours and has costs me LOTS of money.

So, you are express rust bluing using the hot water method. We use that method in the shop with old Belgian Blue sometimes. We also cold rust blue with Rustblue American Formula, a product I make. Mausers blue nicely with that, or German Formula which is the same formula used by the German armories.

www.rustblue.com

quote:

Originally posted by Nick Hughes:
Have used Mark Lees & Gun Goddess. Water from 2 different dehumidifier’s or store bought distilled water. Draw file and polish by hand anywhere from 240-400

To be honest it’s a minefield. I could help you troubleshoot it but would need to know every step of your process from rust cycles, times, temp, humidity etc etc. Chemical can go bad, I’m using 15 yr old Goddess that works perfectly, but some others go bad.
Poor conversion is from bad water, you have to get a good source of distilled water is guaranteed to be 100%. Demineralised is no good. Boiling tank 316 stainless steel. Steaming hasn’t worked for me. The list goes on.
Keep at it.

Use my products and follow my instructions and you will get consistent and predictably good results. It is just basic chemistry, but there are some rules you have to follow. I've got thousands of customers and many newbies getting great results on their first try. I'm available to troubleshoot if you need me.

Bob

I made up a solution of Nitric acid and Hydrochloric Acid with steel wool. I followed a recipe from the web. It is at least 10 years old. I wonder if it will work or should I discard it?

quote:

Originally posted by Aaron Little:
You’re not the only one…in the last two years I have had a hell of a time with rust bluing. It used to not be the case. I don’t know what has changed, and like you I’ve altered certain parts of the process thoughtfully to test where the issue might be. Nothing.

My experience mirrors yours and has costs me LOTS of money.

Try adding the muriatic acid. It definitely worked, I just wish I know what it did on a chemical level and what was keeping the rust from converting before.

quote:

Originally posted by Nakihunter:
I made up a solution of Nitric acid and Hydrochloric Acid with steel wool. I followed a recipe from the web. It is at least 10 years old. I wonder if it will work or should I discard it?

I’m not a chemist but this recipe doesn’t have a good shelf life because the nitric and hydrochloric acids react causing nitrosyl chloride. I’ve heard that the Pilkington solution is made from this recipe and I’ve had a failure using old Pilkingtons.

I gave up on boiling, and steam instead. What I've found is that I need to rust less, and card more thoroughly. More cycles, less rust each time. The first two or 3 cycles on a barrel just barely turn it grayish, and the steam makes it all blotchy throughout. Card that off as well as you can, and it will still be blotchy. But, by cycle 5 or 6, it will start looking good, and by anywhere from 6 to 8, it will be dark black and even. I can get 4 or more cycles per day, since I don't let it rust as much.

For years, I couldn't get dependable results, until I tried again with steam to convert, instead of boiling. Steam has the advantages of taking less space, being easier, and using less fuel. Win every direction.

trying to upload some pictures:

ssdave, which solution did you use?

It looks great.

Dave,
Your giving away all my secrets....I still boil though.
Steve

If it helps, I've done several barrels using Bobster's solution, on both Lilja and PacNor barrels, with great results. I steam the barrels in a plastic pipe, three times.

Someone mentioned browning afterwards; I've wiped the barrels down with linseed oil which has worked for me.

Can't get the work too clean!

SS; your steamer pot looks like the one I built out of an old pressure cooker and a piece of PVC pipe.
For those who are still doing the Medieval immersion process; steaming only uses on quart of boiling water and is far quicker.
USE ONLY BOBSTERS SOLUTION. I have used many since 1974 and his is the best. Bob's stuff will form black soot in one pass; but I usually do 3.
I clean with Tide and a fine Scotch Brite pad. That opens up the pores.
Do not over polish; That closes the pores. I use 220 max.
Preheat your metal; if you put cold steel into the steamer it will condense and streak.
Do not use gun oil! That removes rust; use linseed oil.
Come over and I'll show you how to do it.

SSdave, that looks better than some of the professional rust bluing I have received. Would you mind sharing what formula you used? I love the blue/black color.

Personally I have been on a charcoal bluing kick lately, but that looks fantastic.

I'm using up an old bottle of Pilkingtons. I've used that and all kinds of other stuff for small parts forever, and boiled them. I haven't seen a lot of difference in what formula I used, the difference comes more from how you prep, how you card between cycles, how much you let rust. For small stuff, boiling is convenient and works, I use dehumidifier condensate instead of tap water.

I had trouble with barrels, until I started rusting less and doing more cycles. That was the successful approach for barrels. It's much easier to get a uniform finish and a dark even color if you do it a little bit at a time, instead of trying to get it in 2 or 3 cycles.

True, and if you want a high luster blue or to preserve engraving, lots of short passes and mild rusting is the way. I don't use a rusting box either, just let the solution do its job at ambient temp/humidity, and refrain from rust bluing when it is too warm.

Dave, questions on picture #3, it looks like a failure as splotchy as it appears. Did you continue with more passes and it turned out like the last pictures? Amazing.

The full octagon barrel shown right after the splotchy one is the final product. The splotchy one is after the first steaming cycle, I carded it off and continued rusting, I think the finish blued one is 6 cycles later. Regardless of preheating the barrel before putting it into the steam, I have condensation that leaves that splotchy pattern on the barrel after steaming. It cards off and the black oxide underneath is pretty uniform, and gets better each cycle.

If you are getting condensation on the parts even when pre heated, then there is too much steam in the tube; I use a larger tube and let it flow freely out the top.
I used to get condensation spots until I did that.
At least that is my experience; not telling anyone what to do.

quote:

Originally posted by dpcd:
If you are getting condensation on the parts even when pre heated, then there is too much steam in the tube; I use a larger tube and let it flow freely out the top.
I used to get condensation spots until I did that.
At least that is my experience; not telling anyone what to do.

I should try that some more. Your experience is that it takes very little water, and you let the steam come freely out the top. I tried that, the water boiled away, and it didn't convert the rust well. So, I put a loose piece of aluminum on the top to slow down the steam, it condenses, but also converts the rust well and the water doesn't boil away as much. I'll try free steaming it, and just carding off whatever results, and see how it comes out on my next barrel.

Have not tried the wallpaper steamer yet.

I have a Wagner steamer. I never thought about using it for rust bluing.

Lots of good information here. Thanks for your help Dave and DPCD. When I experienced condensation and splotchy areas thought I failed so I stopped my trials to find for the cause. So next time I will continue with more cycles to see if it evens out.

Here is my steamer, a piece of 4 inch PVC. I let the metal rust for 12 hours, and steam twice a day. The pot was a pressure cooker, and I drilled 4 huge holes in the top to let the steam rise into the pipe. I use one quart of water, preheated in a tea boiler, which makes it fast.
Preheat the metal with a heat gun. I had a hat for it made from a piece of al foil, but the steam still comes out the top and is not held in.
The barreled action and parts hang from that rod, and of course, nothing can touch the sides.