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?
