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waksupi
04-14-2016, 09:13 AM
As for boiling out rust blue, without proper tanks. I came across this on a gunsmith's website, and it worked great for me.

Get a pvc tube, and cut to length needed.
Get a pot to boil water in. I had an old cast iron pot, about 8" in diameter.
Then find a flat piece of metal that will cover the pot.

You should find a flange that the PVC will fit into. This was the most expensive part of the project. I used some 4" pvc since that is what I had laying around. Smaller diameter would be easier to find a flange for. The flange makes it easier to balance the pvc on the pot cover.
Find where the pvc will center on your pot cover, and drill holes.

Once this is done, bring the pot of water with the cover on, to a boil. I did this outside, with a propane burner. Once you have things boiling, set the pvc with the barrel hanging inside over your drilled steam vents. I used a piece of scrap metal, with a hole drilled through, and a wire as a hanger.
Leave your top metal have a bit of venting, to allow the steam to easily circulate in the tube.

Steam for 20 minutes, and you are done.

I simply dropped my smaller parts in the boiling water. You could also make some other smaller pvc container to steam separately if you like.
The steaming would only really need to be for around ten minutes. The extra time I used was for the parts that were actually being boiled, as the temperature was below the steam temperature.
I believe steaming would also eliminate any concern about not having distilled water, as I saw no spots or other problems from steaming, and I have hard water here.
This is the method I used in the Trapdoor Springfield Reborn thread.

PS, you will not have a rough finish, if you do your boil out (steam out) when you have just a very light coat of rust, and use a Brownell's stainless steel buffing wheel made specifically for bluing.

RustyReel
04-14-2016, 11:27 AM
I use a PVC tube as well when rust bluing barrels and barreled receivers. I capped one end, tie it to something so it stands upright, put the part to be blued in and pour boiling water in the tube. Cover and wait 15 minutes or so. Card, apply solution, and repeat. Small parts, as you noted, simply get boiled in a pot. I'm sure this is overkill, but I use another similar tube, put the part in, and fill it with light weight motor oil as a last step in the process.

Bent Ramrod
04-14-2016, 11:48 AM
Small parts can be boiled in an enameled roasting pan on a stove.

For barrels, my desperation measure was to get a whistling tea kettle, remove the whistle (a small piece of metal in the spring loaded plastic spout cover), fill with water and boil vigorously, so a healthy blast of steam comes out the hole in the pour spout. The barrel, greased inside and plugged on each end with a wooden rod, was held by the rods and passed through the steam in the same manner as it would be passed along a buffing wheel, sweeping the barrel lengthwise and turning.

Make sure the floor has plenty of newspaper on it as the drips and rust will get messy. But you can see the red rust turn to black oxide, and when you can't see any more red, give it a few more passes for luck and hang the barrel by the rods in a rack for carding and daubing with more rusting solution. Might have taken a half hour.

waksupi
04-14-2016, 03:28 PM
If the proper heat and duration isn't maintained, rust blue will often come out with a brownish tint. Been there, done that.

Mk42gunner
04-14-2016, 04:37 PM
When I designed a similar setup for steaming wood to make canes last year, I used an old tractor funnel upside down over the pot of water. I used an old radiator hose to direct the steam to the PVC pipe, but there is no reason the pipe couldn't be set vertically over the end of the funnel.

My setup was intentionally built loose enough that the steam was not contained. Bursting boilers are no fun.

Robert

M-Tecs
04-14-2016, 04:53 PM
Hadn't seen this method before. Thanks

Ballistics in Scotland
04-15-2016, 11:14 AM
An old pressure cooker with a piece of silicon rubber tubing hose-clipped onto where the valve would normally be, is good and permits less escape of steam. A PVC pipe cap would be thick enough to screw a small diameter hose tail into.

It is tempting to suggest that if you put the pressure cooker valve on the top end of the tube, you could run it at pressure, and get up to a surer rust-blackening temperature with less risk of running condensation on the metal. I would want to go over to something really strong for that, though, and do it remotely (as you could with electric heating) at the far end of the garden.

nekshot
04-15-2016, 11:19 AM
how did you stop the rusting when you were done? I used to put baking soda in barrel vat but with steam you don't have that. I did a 22 this way and it works great as you outlined it but was wondering how to stop the rust. I tried washing the metal with hot water, soda and a rag but time will tell if it has stopped.

waksupi
04-15-2016, 01:41 PM
how did you stop the rusting when you were done? I used to put baking soda in barrel vat but with steam you don't have that. I did a 22 this way and it works great as you outlined it but was wondering how to stop the rust. I tried washing the metal with hot water, soda and a rag but time will tell if it has stopped.

I always do a final rise using hot water and dish soap, followed by baking soda. I've never had a problem.

oldred
04-21-2016, 09:15 AM
I had started building a steaming contraption last Summer but other projects interfered, glad that happened because after this thread was started I saw a better way to do it! I changed it to what was described here, close as I could anyway with what I had, and finished assembling it yesterday evening so now I need to try it out.

If I could stray slightly from the exact topic I would like to ask Waksupi about slow vs express formulas, is there really any advantages to a slow rust blue vs the Mark Lee Express blue I use now? Back when I started I tried both methods and saw no difference in the results except the slow method just took longer, HOWEVER, there was still a lot for me to learn and I now do several things differently. I have been considering buying the Pilkington formula and trying slow bluing again.

waksupi
04-21-2016, 09:33 AM
I had started building a steaming contraption last Summer but other projects interfered, glad that happened because after this thread was started I saw a better way to do it! I changed it to what was described here, close as I could anyway with what I had, and finished assembling it yesterday evening so now I need to try it out.

If I could stray slightly from the exact topic I would like to ask Waksupi about slow vs express formulas, is there really any advantages to a slow rust blue vs the Mark Lee Express blue I use now? Back when I started I tried both methods and saw no difference in the results except the slow method just took longer, HOWEVER, there was still a lot for me to learn and I now do several things differently. I have been considering buying the Pilkington formula and trying slow bluing again.

It's hard to give an answer to that. Different climates will give different results. It is very dry here, so I use the same steaming set up to suspend the parts in to rust, and it can take a full day to get a nice coat of brown. I think any of the formulas will work fine, as long as they will oxidize the metal. I think the most important thing is to not let a heavy coat of rust build up, only a light coat between steamings.

KCSO
04-21-2016, 11:01 AM
My cabinet was made of clear poly over a 2x2 frame with a hot plate and a pan mounted in the bottom and a 100 watt old fashioned light bulb in the top. I used it mainly for rust browning and an occasional blue job. I could get a nice brown job in 24-48 hours. I would be more help on browning than blue as that is what I did mostly. I had to adjust to the current weather situation as here we go from no humidity to 100% sometimes in just a day.

John 242
04-24-2016, 10:20 PM
Anybody willing to share a pic of their setup, so I can shamelessly steal it for a bluing class I teach? I have quite a few students who'd be interested in this.

flounderman
04-24-2016, 10:36 PM
hot salts bluing will go red or green with too hot or not hot enough but I never saw rust bluing do it. I use the Mark Lee and boil it in a stainless tank.

John 242
04-24-2016, 10:54 PM
hot salts bluing will go red or green with too hot or not hot enough but I never saw rust bluing do it. I use the Mark Lee and boil it in a stainless tank.

When boiling to convert from red rust (ferrous oxide) to black rust (ferrous-ferric oxide), you can end up with a reddish finish if you don't boil hot or long enough. Small parts usually aren't a problem, but larger ones can be. Happens often with barrels and barreled actions because of their mass.

waksupi
04-25-2016, 10:07 AM
When boiling to convert from red rust (ferrous oxide) to black rust (ferrous-ferric oxide), you can end up with a reddish finish if you don't boil hot or long enough. Small parts usually aren't a problem, but larger ones can be. Happens often with barrels and barreled actions because of their mass.

That is why I like the steam method, more heat!

Ballistics in Scotland
04-25-2016, 06:14 PM
What I have used for traditional Japanese lacquering (a rather unpleasant contact poison which hardens by chemical combination with humidity), was polythene tubing of about a foot diameter with thin cane hoops every couple of inches, so that it folded up like a Chinese lantern when it wasn't hung up.

John 242
04-27-2016, 08:50 PM
That is why I like the steam method, more heat!

This may be something I'd like to get into in the future. Might solve a lot of headaches.

MaLar
06-24-2019, 10:02 PM
Ok I know this is an older post. Why use the white pipe over the black?
Can't find 4" white here, lots of black pipe.

Thanks for you replies.

waksupi
06-24-2019, 11:02 PM
Ok I know this is an older post. Why use the white pipe over the black?
Can't find 4" white here, lots of black pipe.

Thanks for you replies.

I used the white, because I had a section laying behind my shed. Any pipe will work, or for that matter, anything that will contain the steam. A long wood box would be just as good.