Question about soldering

[Cory Joe Stewart]

Hello all,
When soldering underlugs are you soldering the sides down, or do you attempt to get solder between the barrel and the lug?   If so how? 

Coryjoe

[David Veith]

I tin both peices then solder them together or just reheat them together. Just remember solder will travel to the heat.
David

[smylee grouch]

David is right, just use flux and tin both, clamp in place and reheat.   Gary

[caliber45]

Coryjoe -- Though likely not PC, I find it easier to make underlugs of flat stock, bent at 45 degrees. Then I solder one "wing" of the underlug metal to the next-to-bottom flat (lock-side), with the underlug extending vertically into the forend toward the ramrod channel. That leaves the underlug "wing" offset to the lock side, but allows a full flat worth of "hold" with the solder. Incidentally, you can save yourself the need to "tin" anything by using Brownells' SWIF solder, which is ground into a paste. (I have no connection to Brownells.) Spread it on, clamp pieces, apply heat. Done. Holds wonderfully well. Never had one come loose. -- paulallen, tucson az

[Cory Joe Stewart]

Ah good, that makes sense now. 

Since the solder follows the heat is there any danger of it all flowing out?

Coryjoe

[Dave B]

Soldering is not difficult if you know some of the tricks. If you have the heat right with good clean surfaces its a breeze but if you over heat it it burns your flux and you must start over. The process of tinning is critical to the proper solder joint IMO. You must take some solder past flux with some degreased steel wool. Heat the surface of the portions to be soldered and test touch the solder to the surface till you see the solder respond. Scrub the area with the fluxed steel wool and you will get a thin coat of solder over the surface of the area. With both surfaces now "tinned" they will bond once you have brought them both up to temp and touch the joint with more solder. I found that using a bore size copper slug on a rod that is pre heated and slid into the barrel at the place the lug is being soldered helps off set the heat sink effect of the barrel. I have had much better results with soldering my under ribs using this technique.

"Since the solder follows the heat is there any danger of it all flowing out?"
"
You only use as much solder as you need to get the joint filled no more. The capillary action of the thin joint will keep the solder in it. As long as you are not over heating the area you should be good to go.

[northmn]

For me the old 50/50 plumbers solder seems to be the least fussy and has worked very well.  SOme of the newer tin/silver combinations seem to be a bit fussy.  50/50 flows into joints the best for me and I ahve sights and lugs that have been soldered with it that have held for years.  As stated, with any solder clean is needed.  I use sand paper instead of steel wool due to the oil issues, but a degrease like acetone can be used.  Another little trick on underribs is to solder on the thimbles with a higher temp solder.  I have one that is very strong and is higher temp than solder.

DP

[Rainman]

Has anyone used J.B. weld instead of solder for this operation?

[flehto]

I now use Swif 95 soldering paste which really simplifies soldering. Sand and clean both surfaces, apply Swif 95 sparingly to both surfaces, lightly clamp and heat both parts but the larger part more so. About as simple as it gets....Fred

[doug]

Ah good, that makes sense now. 

Since the solder follows the heat is there any danger of it all flowing out?

Coryjoe

    it should not flow where the metal is not clean and/or tinned.  I have had problems with filling voids when soldering ribs on double shotguns because the solder will flow right through rather than fill the void if the gap is too large.  Prior to this I have tinned the barrels top to bottom relative to the area between the upper and lower ribs.

cheers Doug

[oldiemkr]

j b weld will work until the first time the barrel gets cold. The metal will get cold and it will release.

Some years ago they took the cadmium { Ithink thats what it was } out of silver solder. It made silver solder flow easier .

Yuo can bring the objects to be soldered up to temperature as slow as you want to. Just until it flows,but if you bring it up too fast and/or burn the flux you have to start over and clean it all up.

[Steve Bookout]

JB WELD!!!!   Oh....my hair's a-turnin' white........ Cheers, Bookie

[b bogart]

Quick grab that emergency Moon Pie Bookie!!!!

[halfstock]

Actually Bookie JB weld ain't nothin more than the old time cutlers glue.

[Acer Saccharum]

Oh....my hair's a-turnin' white........

I thought it was already white?

JB weld:
most of the time we try to stick to materials and methods used in the 18th and 19th Centuries. However, we have been known to use occasional accra glas epoxy or have a stock carved on a machine.  

I have to agree with Oldie maker, the JB won't stay with temp extremes. Soft solder works great. Liquid acid flux works the best on steel. However, rosin style flux can be used, provided you coax the solder around with a bit of steel wool.

The dreaded enemy of all soldering is too much heat. This will cook the flux, and nothing will make the solder flow. You must scrub all down to bright and start anew.

Merry Christmas, one and all.

tom

[FL-Flintlock]

Silver bearing solder is still available in alloys containing 15-25% Cd, lowers the melting & flow points, also helps improve the flow and Cd rich alloys also create a much stronger bond.  Just make sure you have a defibrillator handy before looking at the prices.

[ironwolf]

  yea, and don't breath the fumes.

  K.

[FL-Flintlock]

Good ventilation/process filtering combined with a respirator using an N100 pre-filter over a P100 organic vapor cartridge will mitigate cadmium issues.  I can't help but find it somewhat humorous how some people have a stroke over using Ag/Cd brazing alloy but fail to consider that Pb cable sheathing and other Pb laminates contain Cd ... and no one ever considers their exposure to the potentially high-level Cd, Sr & Th outgasing of batteries.  Ever wonder why there are so many people suffering with stomach ulcers, Cu & Fe deficiencies, gastric bacterial infections and liver failure after using the allegedly "safe" Cd-free alloys containing Zn?  

[Steve Bookout]

FL-Flinter, now you know the REAL reason my hair's white! 
     For a really neat job when I don't have the inclination to tin the parts, I'll drill a 3/32" hole in the bottom of the thimble, flux and heat up the parts.  Then briefly apply the solder into the hole.  That's just another way to get the thimbles mounted without beads of excess solder appearing at the seams where the thimble & rib join.  Any solder remaining can be easily filed out of the thimble with a bent handled file.  Hope you all had a merry Christmas.  Cheers, Bookie
P.S., Tom, I'm upset.  I heard you were nominated for Curmudgeon of the Year over me!

[smylee grouch]

Thanks Bookie for that soldering tip, sounds like it will work great.  Best wishes    Gary

[Acer Saccharum]

P.S., Tom, I'm upset.  I heard you were nominated for Curmudgeon of the Year over me!

Bookie, the coming new year will provide many opportunities to surpass me!


For hard soldering (high heat, borax flux, high silver content 'solder') the parts must fit together very tightly for the solder to flow. Everything must be up to heat, and NOT overheated. I paint both pieces with flux, cut little squares of solder and place them between the two parts. Bring the heat up SLOWLY to let any water boil out of the flux without disturbing the solder placement. Once the water is gone, the heat may be slowly increased to until the solder suddenly sucks into the joint. You will see the part lay down all of a sudden. Remove the heat, let the part cool slowly, then soak or boil in water. You can also pickle in vinegar to get the cooked flux off. It's hard as glass, so let the liquid and time do the work for you.

[FL-Flintlock]

FL-Flinter, now you know the REAL reason my hair's white! 
     

Would that be from the fumes or from listening to people tell you about how many things are going to kill you?   

BTW, saliva causes cancer ... but only when swallowed in small amounts over long periods of time.   

Mark

[JCKelly]

Did I understand this correctly, the discussion is about soldering stuff to a rifle barrel?

Boring engineering stuff, originally published by the god of Mechanical Engineering, guy named Timoshenko, is that a 200F temperature differential is enough to deform steel. So if the solder is running 500F, and a wet cloth keeps the other side of the barrel down below 212F, you have a bent barrel. Not much. But still just a little bit bent.

I spent over three decades dealing with high temperature materials, nickel alloys that do their job somewhere between 1400 and 2200F. Most of the bent, broken, wierdly distorted pieces of nickel alloy I saw were from temperature differentials.

I found it almost impossible to convince a degreed engineer (yeah, well, I am one, too) that restraint of thermal expansion, or temperature differentials, can so distort metal.

Small farmers and skilled tradesmen did tend to understand, based on their experience. 

But I guess I misread, and this thread is on the art of soldering thimbles to the barrel rib. That's just fine. Oh, yeah, and the cadmium was removed from silver solder because cadmium fumes are not so good for one's heart.

[Steve Bookout]

Intersting about the barrel slightly bending.  Think I may have encountered that about 20 years ago on a fowler we were haviing issues with.  Hmmmm.

FL-Flinter, About the saliva thingy...naw, th' Red Man kills ever livin' organism within....an' Moon Pies tones the muscles.  Cheers, Bookie

[FL-Flintlock]

I found it almost impossible to convince a degreed engineer (yeah, well, I am one, too) that restraint of thermal expansion, or temperature differentials, can so distort metal.

Haven't you figured out that the primary focus of modern education is rule number 1?  "Thou shall not allow facts to get in the way of theory or agenda."

   

Mark