rust blueing

[hortonstn]

what type of tank do you use to boil the water?
how long do you let it boil?
what heat source do you use?
i just want your suggestions
thanks
paul

[Meteorman]

You'll get a variety of answers here, Paul, ranging from custom-made SS troughs over propane burners, to soldered up raingutters and Coleman camp stoves.
I've used a PVC pipe with a 3rd of it sliced off (lengthwise) and capped on both ends, laid the barrel in it on spacers (to keep it off the bottom), blocked it up horizontally, and poured boiling water in the trough to cover the barrel. Waited 2-3 minutes than immediately replaced the water with another load of boiling water for another 4-5 minutes soak. 
Seemed to work fine for me. 
That method of course is slightly different than actively boiling the water with the barrel in the water - having not done the latter, I don't know if there's a noticeable difference in the results.
/mike

[kutter]

I use a stainless steel tank now and have so for the last 20 years. Heated by a N/G pipe burner it was finally a dedicated set up to do rust bluing for me.

Before that I had used a variety of things including a heavy fibreglass flowerbox set into a wooden box with insulation in it. The heat source was 2 hot water tank heating elements plugged into the garage outlet. I had to extend the tank and box at one point to take a trap bbl but fibreglass work and a bit of carpentry was simple enough. No gas hookup at that place and I didn't have to pay for the electricity.

Boiling time is usually between 7 & 10 minutes per coating. It should change color from brown to blue/black within a few moments of being put into the boiling water.  If it isn't changing over, the water may be to blame (hard water or too many disolved chemicles in it as in municiple water supply). Trying to use the same tank full of water too many times will give problems too. I usually dump it after 3 trips through it. By then it starts to pick up other contaminants anyway. Clean the inside of the tank too when changing the water.



Instead of a tank, some people use a tube. PVC tubeing, capped & sealed on one end, deep enough to take the bbl and secured upright to a bench.
Place the bbl in it with a wire on it so you can remove it to check progress. Boil water aside (enough to fill the tube w/bbl in it) and fill the tube w/bbl inside with the boiling water.

When water starts to cool, dump water and refill. Boil next refill of water while first is still in the tube.
An inexpensive insulation mat designed for a hot water tank wrapped around the tube will keep the water sufficiently hot for quite a while. Place a cap on it also to help conserve heat.
The insulation matt makes handling the tube full of warm water easier when it comes to emptying it too.
For the very occasional bbl bluer, it works well with an absolute minimum of equiptment.
Just a tube, 2 caps and someplace (stove) to boil water on to fill it with.

[David Rase]

I'm that guy that uses a piece of rain gutter spanned across 2 burners on my stove.   I boil for about 10 minutes before carding, then take the barrel to a 6" wire wheel.  It takes about 6 repetitions before I get a finish that cannot be removed with a wire wheel.
Dave
I am also that guy with the understanding wife. 

[Dphariss]

what type of tank do you use to boil the water?
how long do you let it boil?
what heat source do you use?
i just want your suggestions
thanks
paul

I made a tank from a peices of 4x4 square thin wall steel tube. Cut out the top and welded pieces on the end.
I use a propane camp stove for heat. Sometimes with a hot plate on one end. I have used it quite a bit. But the tank, made from a piece from a friends junk pile, is a little short for barrels over 42 with the breech installed.

Dan

[hortonstn]

ok,
thanks for the info i'm having a tank built, now for the dumb question?
once the barrel is rusted do i card then put in boiling water or do i put in boiling water then card off the red rust??
thanks paul

[David Rase]

ok,
thanks for the info i'm having a tank built, now for the dumb question?
once the barrel is rusted do i card then put in boiling water or do i put in boiling water then card off the red rust??
thanks paul

I boil first and then card.  That is what works for me.
Dave

[B.Habermehl]

Every body does things diffierently. I don't boil till the last carding. I only boil the parts once. I will apply the solution, allow the parts to rust then card with a wire wheel or steel wool. The shorter the rust cycle the finer grained the resulting finish will be. It usually takes about 6 or so cycles to get the brown as dark as I want before boiling it and converting it to a blue.   BJH

[kutter]

Boil first ,,then card,,is the standard way of rust bluing double bbls. The fine grain blue/black dust wipes right off and the finish can be made as bright as you wish that way with some experience and juggling techniques.

The boiling loosens the rust scale as well as turning it from one iron oxide compound to another (the red one to the black one! I can't remember which chemicle compound name is which.)

Letting them rust longer between boiling & carding cyles will increase the matte effect of the blue as the soln is allowed to start to pit the surface.
Some solutions are more aggressive than others and the humidity & temp also play a role.

Getting a coarser finish may be of an advantage on some work if it suits the 'look' you're going after.

I did quite a bit of 'hot rust' bluing where the part(s) are coated and immediately placed in the boiling water for 5 min or so and then taken out, carded, recoated while still hot and back into the water again.
4 to 6 cycles of that gives you a rust blue in about 1 to 2 hrs time start to finish.
I do mostly slow rust finish now though. Different solutions needed for the different processes.
 
There is no one correct way to do rust bluing dispite what some of the experts may say.
Everyone that does it has a different way of doing the process it seems, even if just a little.
There are a few basic rules but beyond that, the results speak for themselves.
What ever way you can achieve them and you feel comfortable using is the right way for you.

[Kevin Houlihan]

What commercial rust blue solutions do you recommend?  Are there any products that turn the metal a more blue color than black?
Thanks,
Kevin

[Bill of the 45th]

Snap, Rust blue is nothing more than a browned part that is boiled to turn the red oxide blu/black.  Color varies from black to a very dark blue. To get towards the blue you need a finer polish on the metal before you start.  More cycles help, brown, boil, card, brown, boil, card and repeat til you get what you want.  Remember this is rust blue, not modern chemical blue like is done commercially.  I think rust blue is a tougher finish than modern versions.

Bill

[kutter]

I've pretty much settled on Laurel Mountain Barrel Brown as my slow rust blue soln. I've used it for the last 20 or more years with complete satisfaction.
As it does a great job of browning,,the added step of boiling transforms it into a fine blue.
I've also used it for damascus finish, brown & black, with the extra etching step included.

It can be aggressive in that it can rust very quickly if the humidity is high along with the temp so you have to watch it carefully unless a matte finish is what you're looking for.

I have used it in the winter months in here where I keep the themostat at 65F. It takes as much as 24hr or more for a coating to form but that is an advantage sometimes when doing alot of work. Plus the coating is very fine grained and the finish can be very glossy which is sometimes needed on the SxS bbls and other parts I normally work on.

To help it along in winter months,, Hang the coated bbl in the bathroom after taking a shower. Close the door and keep it closed. It'll be rusted to perfection in about 1 to 1 1/2 hrs.

I sometimes cut the soln 50/50 with distilled water and even thinner after the first couple of coatings. That slows down the rusting and chances of pitting if that's what you need in the final finish. The small amt diluted soln's are kept on prescription med bottles labled as such. The tight fitting caps make them leak proof.

I would sometimes early on have a difficult time with after-rust using L/M soln. It can happen with any of the soln's.
A long final boiling followed by a room temp soak or thorough wet down with a sodium bicarb soln helps.
I also spray the parts down after that with a common kitchen spray cleaner , rinse and dry. WD40 follows to clear the metal of H2O and then oil.
Using that I've had no problems.
L/M active ingredient is ferric chloride which is slightly PH acidic,,but there is no acid in the soln IIRC.
It does have some copper sulfate in it as coating a part that is warm will allow the copper to 'plate' out onto the metal. Not what you want.
The degreaser in the soln helps with any small areas not perfectly clean but still cleaning the metal should be a top priority in any bluing process. If anything, it helps not contaminate your water, carding wheel & brushes and tank.

I've used probably a couple of dozen different soln's in the past for both quick rust bluing and slow rust. Laurel Mtn is my choice for slow rust and Mark Lee #1 for quick rust blue but there are several fine products available.

[rick landes]

meteor man...would you share some more pics of the rifle you shared with the RB barrel. It appears to be very nice.

[Meteorman]

thanks Rick.
this was rifle build #3 for me, posted back in October
http://americanlongrifles.org/forum/index.php?topic=12835.0
still learning, obviously.

In fact, regarding rust blueing with LMF, you will see a rookie mistake on this gun. (well, way more than one probably!)
a small band of "un-rusted" or "un-blued" metal where the tang meets the top barrel flat.
this is from the choke-tube lube I put on my breech threads bleeding out and interfering with the rusting process.
I intend to go back and fix that during my freetime ()
/mike millard

[Rolf]

I did a series of experiments on rust bluing that might be of interest.
Here is the link http://americanlongrifles.org/forum/index.php?topic=9755.msg92094#msg92094

Best regards
Rolf

[Dave B]

Paul,
I too use galvanized rain gutter from Home depot that I soldered up and heat using a double burner propane stove I picked up from harbor freight. I use the stuff chambers sells with degreaser and browning solution in one called "Laurel Mountain "browning solution. This is a California rifle I built that I rust blued the barrels for.

[kutter]

Some nice looking rust blue work here..shows what can be done with minimum equiptment.

Re; rust bluing case hardened parts (like screws,etc),,they will not blue easily w/o first etching them. Though the rust will form and turn blue/black in the water. It will have very little wearability and comes off the part(s) very easily even after several coats are applied.

One trick was to lightly etch the part(s) with a very dilute acid soln after first letting them heat up in the boiling water. I used it alot on '03 Springfield bolt parts on custom rifles.
I've used hydrochloric and nitric in the past and either seemed to work well. A 5% soln is plenty,,the hot metal will etch nicely with it. Fine grained and even if you do your part. That etched surface will more easily accept the rust bluing then.
Rinse and cool and slow rust blue,,or rinse and reheat in the water and quick rust blue.

Boiling times should not take much more than a few minutes. 10 minutes is more than enough but most I know seem to use a 15 miniute cycle. If the color doesn't completely change over in that time (actually it should change within the first minute), then most likely the water is not acceptable for the process.

Some tap water in some places is usable,,most is not. You can get a way with using it on small parts sometimes in a small tank (bread pan!) but will show it's incomplete change over on larger barts like barrels.

Even distilled water sold over the counter cannot always be counted on to be really distilled.

Some rust blue soln's are not compatable with certain steels either and they just will not give a complete color change,  have a patchy look to the color or both.

You have to experiment sometimes to find what will work better.

I use A/C condensate that I trap and keep this time of year and use the rest of the year. Lots of plastic milk jugs plus a two 35gal (new) plastic trash containers filled up over the summer keep me in rust blue water.

I've had no trouble with my system but I've heard others claim A/C condensate is NG 'cause it leaches copper off the coils in the unit and they mess up the bluing process. I've never had that problem,,and with 2 different central A/C unit's.

Rain water is another possibility, but let it settle after collection as there'll be alot of junk in it from the roof tops and the air itself. Again, some areas have a high degree of chemicles in the air and that supposedly falls with the rain and is in the water and makes it no good for the work,,
Same with snow if you're lucky enough to have that in quantity!

[Dr. Tim-Boone]

I hear blue snow works best!!!   

[Bill of the 45th]

I use unplated screws, and have no problem getting them, browned, and rust blued.  The trick for durability is multiple coats.  Five or more will give it the depth.

Bill

[Leatherbelly]

Do what Rave Rase says! Very nice outcome with that technique. Best I've seen.

[Daryl]

An Aussie gunsmith over on nitroexpress has been experimenting with Nitre bluing, using heat and salts. He said the finish appears to be as durable as rust bluing.  Although the process was withheld, I assume it is a submersion in the salts which are heated to temperatures giving heat colours. The salts then 'impress' or 'fix' the colour in the material.

[Leatherbelly]

  Almost looks like a cobalt blue in colour.

[kutter]

Nitre blue w/ sodium nitrate salts.
We used ammonium nitrate fertilizer for the process a couple of times in a pinch as the sodium nitrate box had been tossed by another worker. It does work.
It's a temper blue color brought about w/o the free oxygen in the atmosphere intefereing with it's forming on the part.
Same idea/different process of course as charcoal blue and later gas oven Carbonia Oil blueing used by most of the mfg'rs.

It can even be done in very fine sand if it's packed tightly around the part to keep the air out.


Just melt the salts in a steel container and bring it up to the temp required for the correct temper color you desire and immerse the part on a wire into it and watch it. The salt is water clear when melted and the color change is easily seen. Takes place in a few seconds to under a minute on most parts but sometimes certain areas lag behind with a reddish cast for a bit.

Some modern types of steel alloys will just not blue well with this method and will always have a reddish color to them esspecially in bright sunlight. Older guns and parts do best with this.

Parts have to be clean,clean before going in,, and dry.

Remember it's an annealing/tempering process as well as a coloring one, but the time in bath is reletively short compared to most annealing directions if you just want color on small parts.
Use it for spring tempering as well (spring temper blue),,or back off on the temp for 'straw color' temper, etc.

A thermometer sold for lead bullet casting is used to check the temp.

Don't get it on you,,don't get any water/moisture any where near it while working with it our you'll be wearing 600F+ splash of it. Same precautions as working with molten lead.

Any salts clinging to the part after pulling from the stuff will dissolve in water,,done afterwards and away from the pot.
Though some souls say they quench the hot part right out of the salts to 'set' the color. You do get a satisfying pop and splatter of water and salts coating flying around when you do that,,but I've never seen it to advance the color fastness any.

In it's molten state that you'll be working with it for blue and blue/black colors, it'll burn right through your clothes and into your skin if it does get on you,I can say that from experience. Protect your eyes at all costs.

Take it up to just under 800F and you'll get a deep blue/black that rivals the early Colt & S&W oven blues. Too far and you get nothing!
Don't let the parts touch the sides of the container, just let them hang in the molten salts.

When done, just let the salts cool and they reharden in the container. Cover tightly afterwards or they'll draw moisture from the air and you'll have a pool of water on top next time.
A heavy but loose fitting cover on top when reheated as it tends to pop and spit a little as it remelts again.

I wouldn't say it's a very tough finish at all,,certainly no where near rust blue. But it's at least as good as some of the modern  hot salt blue and better than torch done heat blue.

[Daryl]

Wow! thanks Kutter. I figured the heat needed would anneal parts.

It's hard to get over the 'blue' that Dave B. got.  Must have something to do with the particular browing solution he used.

[David Rase]

Wow! thanks Kutter. I figured the heat needed would anneal parts.

It's hard to get over the 'blue' that Dave B. got.  Must have something to do with the particular browing solution he used.

Daryl,
Like they used to say in the old Olympia beer advertisments, "It's the water".  Anybody who is short rain water can contact any of us Washatonians.  We have an unlimited supply.
Dave