Silver Soldering Questions

[Justin]

I have never soldered anything before but it seems I will need to silver-solder my front sight pieces together so I have some questions I'm hoping you folks can help with:

1) Can I use "silver bearing solid wire solder" (aka plumbing solder) for this purpose?
2) I need some sort of surface to put the sight pieces on while I am heating them up. I don't have an anvil except the small spot on my vise but even that is surrounded by my wooden work bench so I would not feel comfortable using that. What do you use as a backdrop / working surface for your silver soldering?
3) I accidentally got brazing flux at the store -- I need to return that now and get the proper soldering flux. Is there a particular type that is most appropriate?

[Daryl]

"Silver soldering" to us is what you likely call silver Brazing, which requires red heat + a bit, to melt the solder. Borax is usually the flux.

I've switched to using bricks for my (high temp) silver soldering. Sitting on my vice's anvil (or on a brick) works fine for low temperature soldering with lead or 'silver bearing solder.

About any standard soldering flux works for me, with low temp solders, lead or silver bearing.  High temp Silver Soldering flux is not usable with low temp solders, as far as I know. I've never tried it, nor do I intend to.

[n stephenson]

Justin, true silver soldering is done at a much higher temperature than what your talking about. There are people here that know much more than I do about soldering. I go to my local welding /gas supply store and, buy Stay/Silv solder , it comes with the right flux. I have had very good results with it holding well. Don`t get it too hot !  Just hot enough for it to flow good.     Nate      Sorry Daryl I basically repeated you.

[Justin]

Ah, so do I need a higher temperature torch then for brazing? I bought brazing flux which comes in a can and it says "Anti-Borax No. 2 / Brazing Flux" on the can.

I also bought a Bernzomatic Multi-Use Torch Kit that says it's good for "projects and repairs". It has a steel tube / tip on it but it doesn't say it's especially high heat. There was another kit for sale that did specify high heat but it was about $55 instead of $28 I paid. Should I go with the high heat version? I just checked the Bernzomatic site and they suggest the high heat kit for brazing so I guess I'll be exchanging mine:
https://www.bernzomatic.com/Products/Hand-Torches/Instant-On-Off/TS4000

What kind of bricks do you use? I have some spare bricks sitting outside frozen right now... They were used by a previous owner of my house for landscaping borders. Would those work or do I need a special type of brick?

[Justin]

Oh, I think I'll buy some "fire brick"... Seems that'd do the trick

[n stephenson]

Justin, you don`t need brazing heat. For a front sight and barrel tennons,  I have found the Stay /Silv low temp to be enough. JMHO   Nate

[Nordnecker]

Wait a minute. If you are going to dovetail your sight base then you don't need high temp solder. High temp solder is only needed if your sight is 2-piece or folded and you plan on soldering it to the barrel. Why? Because if you use the same temp solder for both operations, you will melt it out trying to solder it to the barrel.
For low temp operations, you are better off not setting stuff on an anvil or anything that will act as a "heat-sink". Use a pair of hemostats or tweezers to hold small stuff.

[Kingsburyarms]

If you just want to solder your sight into it's brass dovetail base  - this is what I use:

https://www.amazon.com/Bernz-Matic-ST2200T-Micro-Butane/dp/B000PS9TQI

It's  small, it's easy, it works with regular "silver" or electronics solder/flux you can buy at the local Home Depot (the skinny stuff, not the plumbers stuff)  - it will heat fast and will create a nice bond for you - Practice on two pieces of scrap brass or some extra wire you have hanging around - once you get the heating process down, the sight will take all of about 10 seconds. I just heat the brass base, as solder flows toward heat, (with the silver sight in the groove - with some flux on it), touch the solder to the joint, and it will flow right into the joint and seal quite nicely - It's that easy.

Jon

[Justin]

If you just want to solder your sight into it's brass dovetail base  - this is what I use:

https://www.amazon.com/Bernz-Matic-ST2200T-Micro-Butane/dp/B000PS9TQI

It's  small, it's easy, it works with regular "silver" or electronics solder/flux you can buy at the local Home Depot (the skinny stuff, not the plumbers stuff)  - it will heat fast and will create a nice bond for you - Practice on two pieces of scrap brass or some extra wire you have hanging around - once you get the heating process down, the sight will take all of about 10 seconds. I just heat the brass base, as solder flows toward heat, (with the silver sight in the groove - with some flux on it), touch the solder to the joint, and it will flow right into the joint and seal quite nicely - It's that easy.

Jon

Yeah, this is all I'm doing... So the electronics solder with flux core will work ok for that?

[Justin]

Also, my front sight is two pieces and both appear to be brass (from a Chambers kit).

[smylee grouch]

A lot of the silver solder that you can buy has a small veil of flux with it. A reg. Bern-zo-matic propane torch works fine for this stuff.

[Kingsburyarms]

Smylee is 1000% correct - many types and styles of torches - Clean the brass well and make sure it's nice and shiny - don't use any polish or wax type cleaner, 600 grit sandpaper or finer will work just fine, the goal is to take all the tarnish off the area to be soldered.  fit the parts together cold, test them to make sure they have a nice tight fit, then place some flux on the blade of the sight at the joint, (flux is an acid that takes the final "light coat of tarnish and oxides off of metals"), and insert the blade into the slot, and place on an fireproof surface (I use a 1 foot square kitchen floor tile I got for free from Home Depot) or concrete or.. (you get it) just heat the bottom piece evenly for a few seconds, you will see the flux melt and bubble, and then take the solder from the top (not in the path of the flame) and it will melt right into the joint. if it doesn't, heat the base a little more. DONT heat the solder directly with the flame, you want the metal to "accept" the solder, not melt the solder onto the metal.  when the base is hot enough, that solder will flow right in.

Don't use too much, or you will have to file it off later to get that nice crisp joint where the solder is invisible, It's not a stress joint, so all you are doing is bonding, not creating a stress joint.

Try a few practice runs with some spare brass, make some 90 degree joints - you will have fun with it -

Jon

[Hungry Horse]

I use a product that is called Stay-Brite. It is a low temp silver bearing solderand special flux, that melts a a little over 400 degrees, and can be made to work with a propane torch. The sight on my tradegun is soldered on with it as is the barrel lugs. Traditional silver solder require a lot more heat, that ca damage parts, if you’re not careful.

  Hungry Horse

[Kingsburyarms]

The store bought Tin/Lead electrical solder melts very low (188-210 degrees) that's what I have been using... no damage to anything -

[porchdog48]

Use fire brick regular building brick can explode if heated high enough. Found that one out the hard way.

[WKevinD]

I typically use lead based 50/50 for my front sight and silver bearing plumbing solder for my underlugs. Front sight is lower temp and less chance of losing a front underlug. Am I creating a future problem?

[Pukka Bundook]

As others have said, Justin, use soft solder and this can be done holding the parts in pliers.  Keep the heat low, a propane torch is enough, even turned down low.

[Mark Elliott]

Do you really need to solder your sight pieces together?   I rivet mine.    I leave a little tab on the bottom of my silver sight blade that I use to rivet it to a brass sight base.   

[Goo]

Sigh up for a basic metals/silver smithing class at the closest art center it's going to answer all your questions, save you from throwing money down the drain on ineffective tools and establish a foundation handling the challenges of non ferrous metals.   

[Hungry Horse]

Silversmithing class? For what? He isn’t doing anything with silver. And the smithing part of a silversmithing class will help him very little in his current build. He needs a propane torch, low temp melting silver bearing solder, and some practice. Unless he just has too much time on his hands, a smithing class will drag his project out a mile. JMO.

  Hungry Horse

[Mark Elliott]

I took a jewelry making class at my local art center and it did help with my soldering skills.   You do a lot of silver soldering in jewelry making.   One thing I learned was that I was using too much solder.   I also learned that my joints had to be tighter and cleaner, and that you needed to apply just the right amount of heat in just the right place.  I think that I normally use too much heat with the torch that I have.   We only used propane (no oxygen) torches in class; even for high temp silver solder and annealing.

[P.W.Berkuta]

I have never soldered anything before but it seems I will need to silver-solder my front sight pieces together so I have some questions I'm hoping you folks can help with:

1) Can I use "silver bearing solid wire solder" (aka plumbing solder) for this purpose?
2) I need some sort of surface to put the sight pieces on while I am heating them up. I don't have an anvil except the small spot on my vise but even that is surrounded by my wooden work bench so I would not feel comfortable using that. What do you use as a backdrop / working surface for your silver soldering?
3) I accidentally got brazing flux at the store -- I need to return that now and get the proper soldering flux. Is there a particular type that is most appropriate?

1) any soft solder with it's flux will work  - don't mix & match components for best results.
2) A regular brick will work for this one task but a fire brick is good to have around. Vice grips will do in a "pinch" ( ).
3) Brazing flux is for high temp brazing work - take it back.
4) get a book on soldering and joining metals - good reading and you will know who is full of BS when you ask a question like this.
5) practice on scrap metal such as brass to steel, steel to steel, and brass to brass this will sharpen your skills when you do the real thing.
6) don't use too much heat - you will burn the flux and will have to start over. Only apply enough heat to heat the metal being joined & melt the solder. Play the flame on and off the part to heat both parts up for the solder to flow.
7) the parts to be soldered need to be in intimate contact with each other and CLEAN - solder will not fill gaps and be a good joint.

[Daryl]

When soldering, always attempt to get a 1 thou. fit to the surfaces being bonded. (.001" - or  closer)

 

[flehto]

For my low temp soldering I use Swif solder paste and a propane torch.....the paste eliminates tinning. This solder has never failed for closing RR pipe tabs, attaching  front sights on round bbls, attaching hinge plates to Pbox lids and other low temp soldering.

For high temp silver soldering borax flux and a Mapp Gas torch are used. This Bucks County entry pipe is 2 pcs and only high temp silver solder is used. The pipe is formed and then high  temp silver soldered along the inside seam and closing the tabs. When attaching the 2 parts, a round, steel heat sink is inserted into the pipe. 

For attaching the base and  blade on a front sight, I don't use any solder...just a riveteing prong on the bottom of the blade. The blade is closely fitted into a slot in the base and then riveted......Fred