Can silver solder paste be used to silver solder a front sight back on a revolver?

Silver soldering, also known as 'hard' soldering or silver brazing, is a process in which two or more parts are joined by melting and flowing filler metal into the joint. The melting point of the filler metal is above 420°C and flows into the joint by capillary action.
The basic steps in making a silver soldered joint are:-

• Make it
• Clean it
• Flux it (paste)
• Apply heat and solder (brazing torch)
• Cool it
• Clean and inspect it

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Science plus Art

Thank you ! But can I use silver solder paste in the place of solid solder?

You didn't get an answer, but at least you learned something. LOL

I don't do this for a living, but in the silver soldering I learned at a college, the only "paste" was the flux, and the actual "solder" used was in metallic form. The "solder" has to put in place before heating, and is usually set into the flux.
Silver soldering is actually a form of brazing, and the details of the technique differs from lead soldering, in addition to being done at higher temp.


I have put front sights on muzzleloading pistols with lead solder and copper sights, to duplicate actual period guns I have seen in museums, like the colt in the Gettysburg museum.


For any soldering or brazing, the secret to success is getting the material physically and chemically clean, using the right flux, and heating evenly.

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Science plus Art

Thank you! I am familiar with silver soldering using flux and a rod or ribbon of solder but I have found on the net a paste that apparently contains very fine grained solder mixed with flux that can be used for soldering small objects.I just was looking for someone who had experience with this stuff.

Now that I understand what you're asking, no I never used that product.

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Science plus Art

We have used the 'silver solder paste' with great results.
The most important thing is to be sure that all surfaces are absolutely clean and free of oil and or other substances.
USE SPARINGLY, A LITTLE BIT GOES A LONG WAY.
DO NOT OVERHEAT !!!.

Thank you very much!!

For jobs like re-mounting a front sight on a revolver, the silver solder in paste form works really well, actually better in my opinion.

With the paste you can pack it into a barrel slot or coat the underside of a ramped type sight and get an excellent bond.

Couple of things:
We're talking about real silver solder (braze) that melts at temps above 1100 degrees, NOT the soft solder that has about 3% silver and melts around 450 degrees.
The soft solder will seldom hold any type of pistol sight.

Be aware that the high temps will destroy the finish so the gun will need to be totally re-blued.

You need to be careful about the bore scaling from too much heat.

Wait there is silver SOLDERING and silver BRAZING.

Silver Solder is a silver bearing solder that melts around 450f

Silver Braze has a lot more silver and some brass and melts over 1200f.

Braze is stronger than solder, butt, solder is strong enough for sights etc as long as you don't use the barrel for a pry bar. Braze is often used to attach things like carbide to the end of a tool. If you silver braze on a barrel the heat can cause problems and you had better but a protective coating on rifleing. Anything tempered will lose its temper if you silver solder on it. Be better off tig welding. Temp is higher, but more localized because you can heat sink the piece and the tig torch gives instant very localized heat, where any kind of gas torch heats up the part slower and the heat has time to travel farther.

Soft silver solder is fine for sights, every thing must fit tight, no gaps, Plus, it helps immensely to increase strength. Something like just a flat bottomed blade on top of a ramp has little strength soldered. Fitted into a groove and properly soldered you would probably bent the blade before it came out. Even a curved bottom ramp that fits the curve of the top of a barrel will be pretty strong properly silver soldered. When I solder a ramp I fit it to a double groove first a wide shallow groove then a narrow slightly deeper one. Make ramp base to fit. Kind of like tongue and groove. The fit needs to be very tight. NO GAPS. Then, flux and tin (heat up and give them a thin coat of solder) both pieces. Then position parts, heat back up press into place firmly, let cool. Very small amounts of solder should come out of joint. This can be removed using sharp brass scrapers. But, if you coat an area with graphite from say a lead pencil, the flux won't remove it, solder will not stick to it.