Forums.NitroExpress.com

This is some info that I posted on another BBS but I thought it might be of interest to a few participants here, given what goes on in the shops and basements of some participants here.

The only American guns that I can speak to are the Stevens 311’s and the Fox Model B. All of those which I’ve worked on were oven brazed. I’ve been told that some of the 311’s were soft soldered but I have not personally encountered any.

The majority of the cheaper Spanish guns like Laurona, Zabala, Gorosabel, etc., are oven brazed.

I was recently given the barrels from two old Belgian klunkers that were being scrapped. I thought to salvage the top and bottom ribs for future use, as I assumed that these guns were soft soldered. It turned out that they were oven brazed and even with the pre-heating flame of my oxy-acetylene cutting torch, I could not do it. I had the steel beyond cherry red, virtually to incandescent, and those brazed ribs would not even begin to come loose.

AmarilloMike; True silver solder has a silver content above 50%, as a rule. That’s why the darned stuff is SO expensive. Many soft solders have very small amounts of silver and other metals added to them to increase strength, modify flow temperature, etc, but that does not make them silver solders. Both the American and the Canadian Welding Societies classify soft solders as those which melt below 800F.

Here are a few facts for those few who may be interested:

Eutectic solder(62%lead/38% tin), melts at 361F.

50/50 tin/lead solder melts at 420F.

TIX(tin/antimony) melts at 275F and has a strength of 4000psi.

Brownell’s Hi-Force 44 solder (4% silver/96% tin) flows at 475F and has a strength of between 14,000 and 28,000 psi.

Brownell’s Hi-Temp, Hi-Force 44 solder (5% silver/ 95% cadmium) flows at 650F and has a strength of 38,000 psi.

Silvaloy, (a true silver solder), contains 56% silver and flows at 1205F.

Brazing metals (copper/zinc/tin alloys) melt at between 1300F and 2150F.

A few things worth noting are that it takes two to three times the heat to make a proper silver solder joint as it does to make a proper soft solder joint. Those numbers go up to four to six times as much if we’re talking about true brazing. Also, there is a difference, sometimes a fairly considerable one, between the temperature at which an alloy melts and the temperature at which it FLOWS. Watch for the latter when you’re buying solder, as it’s the important number.
Also, the numbers shown for strength are contingent upon a clean properly fluxed, and close fitting joint. If any one of those things is ignored, these numbers go right out the window.

Edited by ronvella (24/01/09 09:59 AM)

Post Extras