doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Barrel rust blue preparation/polishing

I just use tap water,never had trouble.Walter used tap water, and German water is very hard, it didn't cause problems.Water is used only to kill the rust,turn it black, and the work is well carded afterward.Also I don't mask off areas, I just keep the solution off unwanted areas as best I can during the bluing.Afterward, I polish the flats,the sides and rear of the under lugs,rear of the barrels and front of the muzzle with worn 320 grit abrasive.I don't worry about getting water into the barrels,I just tip them to the rear to pour it out and after boiling for 15 min. the barrels are hot enough to dry instantly.If I'm not going to apply another coat right away, I don't card until right before I am.Never let the work go over night rusting, always boil it and card the next day.
Mike

A good source of mineral free water is air conditioner condensate. I collect it in the summer months in plastic jugs.

There's really no need to plug or urethane the barrels if you're just doing bluing. It's necessary when you're etching Damascus, Twist, or Laminated barrels.

Dehumidifer water works as well. I suspect that water from one of those filter pitchers would work also.

What do you use to remove the water based polyurethane from the bores after the job is done Ken? I've been using shellac which is fairly easily removable with denatured alcohol. I've also used rubber plugs with pieces of brake line tubing bent upwards at 90 degrees to vent any pressure above the boiling tank surface. I like Damascus's idea of using a long piece of all-thread to secure the stoppers, but my boiling tank would not be long enough for a few inches of all-thread sticking out of the ends of 30" tubes. Maybe a piece of all-thread just a bit longer than the barrels with a couple pieces of flat stock for hooks/handles, held on by the same nuts that secure the plugs...

Has anyone tried using steam rather than boiling tanks? I saw one set-up on the internet that used a vertical 3" PVC pipe that was glued into a toilet bowl flange, which was screwed onto the perforated lid of a pot. Barrels were suspended vertically in the upright PVC pipe once there was a good head of steam. Said advantages were much shorter rust conversion times due to not having to boil a much larger tank of water. No need for a pipe or multiple burners. Less fuel consumption, and the guy claimed that most of the original gun manufacturers used steam.

I agree that this is a great thread, and there are always new techniques to learn from the experiences of others.

Keith:

I do quite a few high gloss rust blue barrel jobs along with many regular finish jobs and cleanliness is utmost in my operation. Both my rusting tanks are 42" long welded steel. I installed electric heating elements in both ends which boil very even and consistent without the mess and uneven boiling associated with gas burners. I have used both of these boiling tanks for years without any problems.

I have used rod stock with fender washers and machined plugs, of various materials, that I made for different barrel sets that work quite satisfactory when I need them and choose to use them.

Tony Treadwell used my idea and fashioned his boiling tanks like mine and he was very pleased. PM me if you have any questions, good luck.












Best Regards,

Keith,

I use a long steel rod with the end shaped to hold piece of a green scrubby pad. I use that in my electric drill. The pad is cut so that when the two sides are folded in (like a spiral) they fit snug while the rod is spinning. I soak the pad in acetone, and use a hull as a bushing for the chamber. Besides removing the poly it does a real good job of polishing the barrels. I work from chamber to muzzle, and make sure the pad never comes completely out of the muzzle. Someone on this board mentioned using a green pad this way, that's where I got the idea.

What I've read about steam is that you've also got to be able to use dry heat as a part of the process, as constant steam will cause droplets that cause spotting. The Parker Process mentions "wet" and "dry" heat. My drying cabinet (old metal wardrobe type cabinet) uses a large crock-pot full of hot water in the bottom, set on high. I've three rows of rods mounted at the top, the barrels hang vertically on rod hangers. There's enough room for a dozen barrels. It's warm and muggy like an Iowa summer in there. Four-hour rust cycles are no problem.

My boiling tank is made from a cylinder, I use it vertically on a high-output natural gas wok burner. My other tanks are mostly made from 3 1/2" PVC, used vertically as well. They're for Ferric Chloride, neutralization (Baking Soda), Logwood, (I pour boiling logwood in, then soak the barrels). For the Ferrous Sulphate soak I use an open tray, made from a section of plastic rain gutter..

Here's a question of my own. It's about ribs with minor leaks. Whenever I see evidence of a rib leak I use the "two hole" method so I can flush and blow out the liquids with compressed air. After completion, do you put anything into the rib void? I've read that some use shellac. I've got a cutting edge rust inhibitor, I'm considering blowing that into the rib and then following up with shellac to prevent corrosion.

Doug, I've admired the level of gloss you are able to achieve with the rust bluing process. Some say it can't be done, so why polish beyond 320 grit? But you and CJO and a couple other guys manage to get a beautiful gloss. I do much better than my first attempts where I was using a homebrew solution with too much bite and overly long rusting cycles, but you can bet I'll pick your brain the next time I do some barrels. I haven't done any rust bluing for a couple years, and I'm hoping to do a few sets of shotgun barrels, a Wickliffe 76 .45-70 falling block barreled action, and a .32-20 revolver this spring if time permits. I'm concerned about the Wickliffe because many of the original factory hot blued jobs have plum colored receivers. I made my boiling tank out of 12 or 14 ga. stainless with welded ends, and I made it only 34" long figuring that the longest barrels I'd likely do would maybe be 32". I use a home built pipe burner that uses natural gas and works pretty well, but I like your idea with the electric heating elements. Do you recall the wattage of them?

I'm still intrigued by the steam process for rust conversion. The set-up I described earlier looked a bit top heavy and prone to tipping over, but the guy did caution that the steam chamber had to be very hot to avoid condensation and subsequent spotting on the barrels. I was also wondering about the PVC pipe becoming soft from the heat too, because I've bent 4" schedule 40 after warming it with a heat gun. I haven't had any problems with boiling my parts, but am always open to something that might work better. That's why I was hoping maybe someone here had actually tried it.

Ken, I've only had a couple sets of double barrels that gave off a small stream of bubbles indicating a small rib leak. Both already had a small weep hole drilled in the short rib between the lump and forearm loop, presumably at the factory. I flushed them repeatedly with baking soda solution after bluing, and followed with isopropyl alcohol in a syringe to mix with any water left between the barrels and ribs. Alcohol and water mixes great... just like with Bourbon and water! Then I put them in a large solar oven (whatever vehicle I wasn't driving with the windows rolled up!) for a few days to let the heat drive out any remaining moisture. Then I sprayed into the weep hole with Starret spray lube.

Several years ago, I bought some junk double barrels to practice rib jointing and soldering,and when I removed the ribs on a "nice" set of Baker Damascus barrels, the area in between was somewhat rusty and filled with debris from manufacture, but there was no evidence that corrosion had been actively eating its' way through the barrels. I think we may worry too much about what goes on in there because the entire area was certainly tinned prior to soldering. Yet I've read where guys say they have found barrels pitted clear through between the tubes. So was this corrosion from the bore outward or vice-versa? I guess it's possible we might have to re-do a set of barrels if we ever damage them, so something like shellac might be less likely to give us fits years later. Before anyone gets upset at me destroying a "nice" set of Baker Damascus, let me say that these barrels were almost perfect except for a small area about 8-9" ahead of the breech where something severely rusted the left barrel and top rib. The rust had actually eaten clear through the barrel. Rabbit blood? Battery acid? Who knows?

I would just like to add a few things that my post did not make very clear. Firstly about the rust bluing process the people who were undertaking this where doing it to earn a wage so their outlook was more along the lines of speed and only wanting do the work once. So more often than not they were using express rust bluing formulas each set of barrels took approximately half an hour from start of bluing to finish, though they did sometimes use formulas not containing mercury and only very low levels of acid to give that blue with a mirror type gloss though taking more time to complete and costing the customer more. Now express formulas had vast amounts of Mercuric Chloride in their makeup so it was inevitable that some would find its way in to the boiling tanks, now Mercuric Chloride did not get the name Corrosive Sublimate for nothing and as they say prevention is far better than a cure because if you do get it in a gun bore it can cause rusting days and sometimes weeks after the work was completed. The bores of the barrels where plugged to keep this out as well as any residual oil in, and if you are processing may be dozen barrels a day the boiling water was probably a strong chemical soup by the days end. Also the pitch in the shellac was there as an aid to its removal no black all traces of it is removed and why clean the bore if there is no need to, so keep as much foreign matter out as possible.
Just a couple of things now rust under the ribs in the barrels initial manufacture especially the top makers here still use the traditional Colophony (Tree Resin) as a flux the reason is twofold firstly to aid the solder to flow at lower temperatures and second it would cover a considerable amount of the bare metal surfaces under the barrels ribs slowing down under rib rusting. And finally after bluing was complete the barrels were put in to a form of dewatering oil based on Lanolin if while re-bluing there where noticeable air bubbles emanating from a barrels ribs these barrels where placed in a hot cupboard for a time, then placed in to a cold dewatering tank and as they cooled down the oil would be drawn under the ribs. The barrels were removed from the dewatering tank and left to drip dry then given a polish with a leather pad improving the surface gloss.

From the photographs posted by PA24(Doug in Utah) in the past and now, it is my opinion that he has learned that polishing is the key to the success of blacking barrel to get the results that the great barrel blackers of the UK get and have gotten through the years. I do not know what blacking solution that he uses but it is beautiful and works very good and his boiler set up is excellent as well.

It is good to have a topic of learning and advice giving on this BBS as that is the way it was in the days of it's origin. The excellent barrel blackers are not keen on giving out their formulas or techniques. I remember back 13 years ago I was asked to leave the workshop of the famous color case hardening company in Price Street, as the owner was and had reason to be protective of his processes---the best of the best of the world. Some of you will recall the author of "Birmingham Gunmakers" fame, Doug Tate was also asked to leave this shop. I was sadden to see this grand old gentlemen who knew all the secrets of blacking die last year. But he passed the secrets and mysteries of the trade to his sons. Barrel blackers are the same.

From my observations in the UK and USA, no single blacking or browning formula works the same way throughout the regions of these countries due likely to atmospheric, ambient temperatures, shop conditions and so forth--thereforth you do not find a single formula being used by all the trade. However, one issue paramount and singular consistent of the techniques of the very BEST blackers is: POLISHING; and polishing means hours of hand work with emery cloth using grits well beyond 320--or at least "worn out" emery cloth strips.

I believe that it is the degree and amount of hand polishing that both Doug of Utah and I use to arrive at barrel gloss that is almost identical--with likely very different ambient conditions and blacking formula.

Desmond Mills, the highly respected English gunmaker/gunsmith late of Purdey's and Churchills; and now retired or mostly retired, has this to say about polishing of barrels prior to blacking: "...because the sharp corners of the ribs, the breech and muzzle ends of the should be preserved, THIS means careful handwork and the FINEST grades of emery cloth should be used. The exterior of the barrels CAN be wheel polished and MUST be so highly polished that they look like they are chrome plated. THIS forms the foundation and quality and appearance of the barrel finish. .....Once the barrels are PERFECTLY polished and next and absolutely essential is degreasing......"

I have avoided using the soft cotton wheel (I plan to give it a try sometime) as mentioned by Des, but nevertheless I attain the chrome plated appearance with finest grades of emery cloth, with the final polishing using "worn-out" emery cloth strips of the finest grade grit I have in my shop. The formula I use is the Swiss formula from Algiers book, as it works well in a moderate to high humidity region--you just need to adjust the amount of the 100% alcohol used for your ambient conditions. The alcohol needs to be pure and near 100%--I use the 96% grain alcohol one can procure at a liquor store.

It should be evident by what Des has written in his book above that he is sharing with us what he has seen done by the best of the best barrel blackers who did Purdey and other best quality gunmakers work in his then 30 years at the bench when he wrote his book in 1985--thirty years ago.

I hope this above helps some of you.

I have seen plenty of gloss barrel blacking done in the UK for the trade and it looks great until you place in in the light of day and see all the work that needs to be done by proper polishing that is showing under the blacking grinning back at you as Jack Rowe is fond of saying. Tradesmen cannot spend the polishing time it takes to make a barrel perfect, if they are being paid for a quick ordinary job.

I have seen little (almost none) high gloss work in the USA, until Doug showed us his work. Is it possible that barrel blackers here do not know what they do not know?

Kindest Regards;
Bv

Just a couple comments.Years ago, the barrels(german)were completly tinned before ribs were attached, to prevent rust under them.Then this practice went away, likely due to cost of cleaning the excess off.If a leak indicates a rib comming loose, the bluing should stop until the rib is repaired. With regard to applying a rust preventing oil under the ribs, after bluing;I watched Walter Grass "worry" a piece of chord through a threaded hole in a bottom rib(using scribe and compressed air)and then soak the chord in Ballistol.With regard to using steam,I had a rifle barrel start turning black during rusting,because of temperature and humidity during an Alabama summertime.
Mike