Newbe - first time cold rust blue

[oldred]

Rust blue is not like hot blue that is completely dependent on the surface gloss of the metal to produce the gloss on the oxide layer overlaying the metal. With hot blue whatever finish the metal is taken to is going to be pretty much what we will have wnen finished because that is pretty much used just as it comes out of the tank so whatever surface gloss, or lack of, that we have at that point is all we are going to get. With rust blue the surface is abraded slightly as the layers build up and is thus smoothed somewhat much like sanding between coats of paint, of course by far we are only removing the soft oxide residues but still as the progressive layers are added the surface is leveled out over the microscopic valleys and peaks of even the 320 or so grit abrasive scratches so whats the point of going any finer? From talking with folks who have a lot of experience using this process and from my own limited experience with trial and error it seems that about 320 grit is optimal and polishing the surface past that is counterproductive and does little or nothing to increase gloss, it does however cause streaking and blotching problems and makes it MUCH harder to get dark and even coloring. When I was first experimenting with the rust method I even went so far as to blue 3 flat pieces polished from 240 grit to 600 grit (I even tried 1000 grit once but that didn't work well at all), there was almost no difference at all between the 240 and 360 grit surfaces in either color or gloss but the 600 grit took several more cycles and never did get as dark as the other two, gloss was no better at all than with the courser grits. It has become quite apparent to me that anything finer than about 320 to 360 grit is not only a waste of time and effort but can actually result in a less attractive finish.

[Chill Wills]

I finish with 320 paper then red Scotchbrite lengthwise on the barrel. Then I start the rusting process. Mike, You don't want the damp box dripping with humidity. Water spots are hard to deal with. It sounds like you are learning a lot.

I agree on a 45-70 being too much for a kid to start with. The 40-60 Maynard should be OK if not loaded too heavily. I'm taking a 14 year old to shoot his first BPCR silhouette match tomorrow. He'll be shooting the 40-50 SS that my son shot. We went practicing last week and I think this kid will do OK.

Yes, I did find out that the steaming pan of water was too much plus in talking with two of the guys at the match yesterday that have done some of this, having the barrel in the box horizontal was not the thing to do and they said to turn the box/set-up vertical for a more even outcome. BTW-John, you are getting two thumbs up for making time to bring a kid to the shooting match. Good for you!

After I got home from hte Wyoming match last night I rusted the barrel - starting the 4th cycle. This time I used the box standing up and just had cold water in a shallow pan. This morning I had some light rust and boiled it. It is boiling now and I will card it as I get the chance this Easter family morning. The barrel came out of the water kinda ugly and streaky but maybe carding will remove all that surface UGLY!

[Chill Wills]

Carding really did clean up the surface a lot. Things are looking OKAY. Not great but the barrel is passing the three foot test. Close inspection shows a lot of fine imperfection. Maybe two more cycles will fix some of this.

Overall I am happy with what I see.

Barrel number two will have a more streamlined system.

[LAGS]

When you say " Imperfections " what do you mean ?

[LIMPINGJ]

You might try a dry heat source like a heat lamp or small ceramic heater to pre heat the box the piece in it. Then introduce some steam to start the rusting. The warm metal should not condense the water vapor and result in spots.

[LAGS]

I just let the bathroom steam up from the shower or Tub.
Then I turn off the water and hang the parts in there overnight.
But then I was single for 17 years and had a spare shower in my house.
But now, I just have a good wife who doesn't mind me doing things for my Hobby in the second bathroom.
But I have found that once the metal starts to rust, you can move the metal parts out of the steaming room and hang them in the garage if it is warm.

[Chill Wills]

When you say " Imperfections " what do you mean ?

I tried to capture it in pictures but I can not get the light correct to show what I am talking about. The pictures just show what looks like a nicely blued octagon barrel. The detail is hard to capture. I would describe the imperfections as small lighter spots. Water spots might be what I would guess from the rust cycle that I had the barrel horizontal in the sweat box with the pan of hot water. I think vapor condensed in the air or on the barrel - but only on the top sacrifices and produced heavy rust. The under side had an even coat of red rust and carded out to a very good, even and a nice smooth blue. The top looks like dark blue with thousands of < pinhead size lighter spots. It is kinda like the heavy red rust beads burned down through the first layers under it where the water might have beaded up on the tops.

Today's rust and carding removed and blended this spotty contrast to about half. In other words, it really came a long way to having fixed it. Now the barrel is back in the box for the night (cycle #5) and will be out for a boil and carding in the AM before I start my work day. I will do at least one cycle after this one no mater what, this way I can see how much blending and repair I can make happen.

[LAGS]

I let my parts Slow Rust for 24 hours.
But I do not have it in a steam environment, where it can collect moisture.
The room I put the parts in has a light steamy environment to start off, but that dissipates in a few minutes, and just remains Lightly Humid.
I also always rust barrels hanging Vertically.
Very few times have I ever had water condense and create spots, and that usually when it happens, is up against things like where the receiver and barrel come together and has a slight Step, or sight bases are on the barrel already.
I hang the barrels vertically because I do not plug the ends of the barrel, and would not want condensation to collect in the rifling if laying down Horizontally.

[Chill Wills]

I let my parts Slow Rust for 24 hours.
But I do not have it in a steam environment, where it can collect moisture.
The room I put the parts in has a light steamy environment to start off, but that dissipates in a few minutes, and just remains Lightly Humid.
I also always rust barrels hanging Vertically.
Very few times have I ever had water condense and create spots, and that usually when it happens, is up against things like where the receiver and barrel come together and has a slight Step, or sight bases are on the barrel already.
I hang the barrels vertically because I do not plug the ends of the barrel, and would not want condensation to collect in the rifling if laying down Horizontally.

Yup. I am learning.
I am just using room temp H2O now and for sure - standing up the box and barrel.
My bore and rifling are looking good thankfully so no problems that way.

I will be starting my 50-90 half round barrel this coming week and I think this one will use the much improved knowledge I have gained here. Thanks to all who have been willing to take the time to write about bluing. LAGS - I can really tell you are into this and have spent time working it out.

I am delighted that the process is as easy as it is!

[LAGS]

I learned how to do the Slow Rust Process in a Custom Rifle Building Class years ago.
Since then I know I must have done over complete 200 guns.
So Yes, I have had a little practice.
Once you do two or three guns, you are going to wonder why you hadn't tried this sooner.
But I am constantly doing parts like Triggers, floor plates, sights, and scope bases or other stuff for other gun repairs, rather than just cold blue the parts.

[onelight]

@ Red Bear.
Slow Rust Bluing is one of the Easiest and longest lasting bluing jobs that you can do at home, with Minimum Investment.
It will not give you a Polished Hi Gloss bluing.
But the protection is second to none as far as Bluing Protection of the metal.
These rifles, as are almost all of my rifles are done in Slow Rust Bluing at Home

Those look really nice.

[oldred]

You might try a dry heat source like a heat lamp or small ceramic heater to pre heat the box the piece in it. Then introduce some steam to start the rusting. The warm metal should not condense the water vapor and result in spots.

That's a very important point that's often overlooked and has caused failed bluing jobs. The metal needs to warm enough not to condense water droplets on the surface when exposed to the humidity otherwise spotting and even steaks can occur. I usually warm (that's WARM not hot!) the parts to the point of actually being just a bit too warm so it guarantees no condensation, the metal will cool to the rust box temperature in just minutes anyway and there's no possibility of drops forming.

[Chill Wills]

I am near completing my second barrel. It is Badger half octagon 50-90 SS for a Remington rolling block hunting rifle. The first barrel I experimented on liberally as I worked through six cycles of rust, boil and card. I will be redoing it again at some point but it was my "try" barrel and all and all, it really did not turn out all that bad. The one heavy rust cycle burned down through for lack of a better term and I was never able to get it to reblend back in.

This second barrel job is going fine. Not professional by any means but will be a good blue job. I have completed three rust coats and two cardings and the barrel does look great where it looks great. The few problems with it are in the application overlap seams or where I have stopped and started to get past dovetails. Applying the Laural Mtn solution evenly from muzzle to breach works well for the most part but I do get a slight line showing up in some cases running long-wise with the barrel after carding. Also, I have found that any stutter or incomplete whetting like on the end of a pass that has to be fixed by touching it again shows up as a small imperfection later. I may need to get a better application set-up, maybe a cradle to hold the barrel and easily turn it in order to get long complete passes. I still am wondering what to do about the overlaps as I coat the five or six passes to get solution applied all around the barrel.
This current 50 cal barrel will get a few more cycles and that may even it out - or not.

Professional level work would be zero imperfection found anywhere and I am not there yet.

I am taking down and preparing the rolling block action, lots of pitting and banged up areas. It would look best color cased but I will blue it too and see how it turns out. It will take some work to prepare. The lower tang/trigger guard will be some work getting it looking good. The hours spent doing that interest me the least. It is about as exciting as washing pots and pans but I just have to make myself not quit early and stick with it to get out all the flaws.

[LAGS]

I wish we were there to Walk You thru this rather than trying to talk you thru it.
That is why I am glad the slow rust bluing was part of the custom rifle building class.
I was lucky to get hands on instruction from a trained professional.
But you will figure out what you need to do to make things turn out the first time.
My other friends that were not near me, started out on old Junkers that they didn't care if they made mistakes.
And in no time, they were getting Professional results.
Hang in there, and it sounds like you are thinking of other ways like you cradle to make things work better for your situation.
I too often have to make adjustments in my process depending on the rifle and sometimes the metal too.
Not all metals rusts the same, or Blue the same.

[Chill Wills]

I wish we were there to Walk You thru this rather than trying to talk you thru it.

Yes, I hear you.
It is too bad the distances are so great. A mentor for a beginner for this or casting or loading BP and a host of other things we do is so handy. BUT, here we are in the age of the internet and it is the next best thing to being there. Hmmmm, ....sounds like and old advertisement for long distance phone service.

I do thank you and others who willingly share knowledge.
After I knock out my first thousand rifles I will be better at it
Hopefully before then.

[LAGS]

I bet you hit excellence at the fourth rifle.

[Green Frog]

The reason you Boil the water or use Steam for that matter, is because at 212 degrees, the oxygen is separating from the hydrogen in the water.
Oxygen is what causes the rust.
Bluing is nothing more than Red Oxide , converted to Black Oxide.
It is like a Shovel.
You buy a new Shinny shovel.
Once you use it, it gets moisture on it, then if left to sit, it gets rust on it.
Then next time you use it, the rust scrapes off, and a it will rust again.
If the process is repeated over years, the shovel will form a dark Patina or even Brown Patina.
Then it will no longer get red rust on it.
So look at a 20 year old shovel and wonder why, if it is kept out of Water with Oxygen in it like Rain, then why has it not rusted away.
That is because it self Blued or Browned over the years.
Cold rolled steel is the same way.
That black coating on the metal is from quenching it in the manufacturing process.
That steel doesn't want to rust until you expose the bare metal like cutting it or scraping it while handling the metal.
But once water hits the bare metal, the Oxidation process starts all over and it starts to rust.
It is more the minerals in the water that speed up the rusting.
That is why you boil your parts in Distilled water.
It has no Minerals.

There is a lot of good, practical info in this post, LAGS, but one glaring misconception. As a retired Science Teacher, I have to clarify... water does not separate into hydrogen and oxygen when it boils. The molecules of H2O simply lose some of their mutual attraction at phase change and become a vapor (gas phase) of those same water molecules. Otherwise, every time your wife put the tea kettle on to boil, she would be generating explosive hydrogen gas in your kitchen... a most dangerous state of affairs!

It is the heat of the steam and oxygen coming out of the air and/ or chemically separating from the water when it reacts with the iron atoms in the steel that makes rust, not free oxygen in steam as a result of the phase change. The heat in the steam provides energy to speed the reaction, but rusting will take place even in a cool environment. I’m probably not making this as clear as I should, but I’m used to doing a PowerPoint presentation with colorful images to make my point.

Froggie

[LAGS]

@ Green Frog.
Thank you for a more detailed explanation of the boiling process and the changing of the molecular properties of water when heated.

[Chill Wills]

It is interesting to see how different pieces of metal take this Laurel Mountain slow rust blue. I completed the second barrel, a Badger 50 cal. and took a very good deep blue. A nice job on all areas but one small spot on a flat where the sight was to go. The milled out place interrupted the even application and I never could blend it back. It is like it is a burn-out and does not ever take blue after that. Overall the job looks Okay but, if I was pro and selling blue jobs I would have to start over.

That barrel goes to a smokeless military Remington rolling block action I cleaned up. Also the rifle has a metal butt plate. That metal in the action and butt plate did not act like the barrel nor did they act like each other. I blued the roller action frame and some screws with the butt plate as a group. They were slower to start to darken. Three to four cycles of rust and boil/card and they looked sickly - streaked in some places and no blue in others. Then on one cycle it really pulled together and two more cycles made them black black! The transformation was great! I have to say I was worried there for a time.

I still need to clean up the lower tang and trigger guard and blue it.