doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Invisible sleeve joints and damascus

Hi Stan, could the barrels be flexed apart at the muzzle end if the ribs were removed ? Maybe that would create enough room to work.
I'm not picking on what you say , just wondered.
I know there are some very clever and ingenious welders out there.

A small diameter 2% thoriated tungsten TIG electrode sharpened to a needle point and extended out a bit further than normal from a very small diameter ceramic cup can fit into a very small place, along with the filler rod. The ribs would of course be removed during a sleeving job, but the welding is done so close to the breech that spreading the muzzles apart wouldn't help much at all. I have no familiarity with laser welding, but I wouldn't be surprised to hear that it could be done in even tighter spots than TIG.

Hi Keith, I have a pair of scrap barrels here that I'm practicing rib relaying on and there's a surprising amount of movement between the barrels at the muzzle end when the ribs are removed which got me thinking that the repair toward the muzzle that Stan had done could've been made possible that way.
I see your point (no pun intended) about a fine Tig electrode too though. I have read about and seen pics of the sleeving process but ideally it'd be good to see the job being done to understand the work involved, I don't do any work on barrels other than blacking/Browning and raising the odd dent here and there as I'm not qualified or experienced enough to do the technical work but I'm intrigued with the whole business .

Remember the replacement barrel is machined and inserted into the monoblock. The joint is a lap joint or a socket weld. The first barrel of a pair is easily welded all around. The second takes a little push, and a little pull, to bring the filler in between the barrel set. Not unlike a pipe fitting.

The ribs were of course off the barrels when the weld was done. Keith Kearcher did the work. I was removing a bulge when the top rib popped loose. I removed the bottom one and sent them to Keith to finish removing the bulge, then relay the ribs. When he finished removing the part of the bulge between the barrels he found a tiny crack where the bulge had been. I asked him what he thought and said let's try welding it up then testing it, as it was only about 8" from the muzzles. He ran a pretty good bead dead between the barrels, but I couldn't say whether or not he sprung them apart in order to do so.

SRH

Although probably not absolute one should be able to mike the barrel OD's at a given point then measure across both barrels at that same point. When this measurement across the barrels becomes greater than the sum of the two diameters then it can be reasonably safely assumed there is now a gap between the two. Barrels are normally "Jointed" in at the breeches for some distance until their taper causes them to no longer touch.
At the normal distance for a sleeved joint there would be little "If Any" between the barrels. I believe the purpose of either the weld or solder is to prevent the tubes from moving forward, not to per se add strength to the barrels. It would thus seem that on a weld job sufficient surface could be covered without having 100% of the circumference welded.

The bicycle industry uses TIG welding more than most. For reasons of srength the welds are proud of the frame tubes. If things need to be beautified they fillet the welds, adding a gentle curvature over the weld "waves". As far as I can tell flate faired welds require V chamfers on tubes and are regarded as less durable than full weld frames.

Maybe they know things we do not.