Silver solder?

[Paladin UK]

Okey Dokey...........

In the good ole bad ole days BEFORE Butane, Propane, mig, tig `n` whutever else comes ta mind fer joinin metal .... How did gunsmiths get consistant heat fer silver solder??

I got me reel problems just tryin ta silver solder a lug on a barrel!!        `n` yet Sarah my bootiful 1905 16g SXS has got her barrels silver soldered right along the strap!!

How did they do it???

Paladin (Whuts gotsta know  ) UK

[Cohagen]

Paladin,  I know they used a special flux for silver solder.  You also need higher heat than with regular solder.  You now have the extent of my knowledge.  Didn't take long did it.

Cohagen

[Montana Slim]

A fire-forge would certainlly be hot enough.

I've silver-solder repaired a variety of things in years past, including a trumpet my friend decided to "spike" in the end-zone during a football game.....but I digress......

Modern workshop - Your gonna need a Mapp-gas or oxy-gas setup at minimum, I used an oxy-acetylene welding rig.

Cheep american shotguns back in "the day" were generally brazed (much stonger than silver solder).

Barrels on shotguns were usually fluxed well between the barrels and rib, wrapped with the solder, then clamped/fixtured together, placed in a large oven to bake. at the right temp, the solder flowed to the fluxed joints......Well, something like that.

Regards,
Slim

[Delmonico]

Brazing and silver soldering was simply done in a forge, but one thing most don't know, you have to change the coal after that before you can forge weld iron.  I contaminates the coal, but same with gas or any kind of electric welding, won't work with even a trace of the other stuff.

[Professor Marvel]

Greetings My Dear Paladin -
The other gentlemen are all correct, if I may elaborate -
the methods of joining two pieces of metal with a different alloy are brazing (joining with brass alloy) and soldering (joining with lead alloy).
Due to the melting points and the alloys involved, brazing is typically higher temp, ~ 1600-1800 deg F and stronger. Soldering is typically low temp
~400-500 deg F. and weaker since the lead alloy is not as strong. Silver Solder, or Silver-Bearing Solder has varying amounts of silver in the alloy for strength, and the melting temps vary from a low of 500 deg  F to a high of over 1700 deg F.   Jewelers actually use 90-95% pure silver alloy as a solder.
Silver solder usually affords great strength at a lower temperature. Sometimes High Temp Silver Soldering is called Silver Brazing. This site
has some very good info: http://www.silvaloy.com/hiag.php

Silver solder used in gunsmithing  is a tad different, I will allow Brownells to explain the various products:
http://www.brownells.com/categories.aspx?c=4809

Generally the flux used is intended to clean the metal chemically and reduce any oxidation until the solder can flow and bond. In soldering a flux is often an acid flux, but in blacksmithing one files the work clean and fluxes with Borax which quickly flows and forms a glassy barrier to air.

Shotgun work is most tricky and some makers  used a combination of brazing, silver brazing, hi-temp silver solder and mid- or low- temp silver solder.
The reason is to use the highest temp material for the first joints, then a lower temp, etc, progressing until the last joint was made. Other held everything together as Montana Slim related, and oven-brazed.

Soldering can be tricky since you need to heat the largest part, apply solder to it till it flows (a very tiny amount I might add) then apply the smaller part.
I just now silver-soldered a Remmy lever latch to the underside of the barrel in just that manner.

Here is the hard part - you DO NOT want any of the  other joints to melt! If you should apply too much heat and start to separate the ribs from the barrels, well sir you are just plain toast. That is one of the most common Professional Shotgun repairs, and it is not cheap!  Some gentlemen " have the touch" and they ribs come back on like magic, and the rest of us can only MARVEL at their magic. I am STILL having trouble silver soldering a 16" under-rib to a round single barrel fowler.... I started about 3 years ago and keep coming back to it periodically... it seems that certain metals just plain resist the solder somehow and one needs to divine the proper alloy it really wants...

In the Bad Old Days, heat was applied via Forge, Oven, Gasoline or Alcohol Blowtorches, and even Lung Power blowpipes over various flames such as alcohol lamps or even candles. Here is an example of how it is done with an alcohol lamp: http://www.appropedia.org/Brazing  and
http://www.modernmicroscopy.com/main.asp?article=78&page=3

hope this helps, and have fun
yhs
Prof Marvel

[Paladin UK]

WOW!! 
What more could ya ask fer!! some really innerestin replies!!

Yessiree this place is `THE PLACE`!!



Paladin (What now knows a bit more ) UK