Silver soldering

[Nick1911]

Can brass be effectively silver soldered to copper?

If so, is there any trick to it?

Thanks!

[PTK]

Yes, and yes, use flux and clean the metal prior.


Although, I'd use "metal solder" before silver solder, and low-temp braze before anything.

[Nick1911]

Interesting.

On second thought, I'll probably go with copper, though.  Raw stock is less available, but I have experience soldering it.

Jim147 and 280plus will love this, but I've taken the hacksaw to my A-Coil, and am machining some new bits to solder in. 

My friends and family think it's a cool project to undertake.  But really, it's just born out of me being in a really hot, humid house right now, and also being thrifty to a fault. 

[230RN]

Don't underestimate the amount of heat you'll need.

Don't forget that large-ish parts will sink a lot of heat away from the join site.

Assume it's toxic cadmium silver solder unless you know for sure it's not --use a well-ventilated area.  I think it was supposed to be more-or-less banned, but some of it is still around.  I've got about 10 oz of it and although it will take another 70 years to use it up, I refuse to sell it to anyone.

[Hawkmoon]

Yes, and yes, use flux and clean the metal prior.


Although, I'd use "metal solder" before silver solder, and low-temp braze before anything.

The term "silver soldering" is frequently used in gunsmithing, and the process to which it refers IS brazing ... not soldering with silver-bearing solder.

Go figure.

[PTK]

To me, and all of CST, silver solder =/= braze. They are two very distinct processes. :)

(and yeah, I know, it's all solder/braze/weld, there are only three categories, but the material for silver soldering isn't used for brazing)

[CNYCacher]

Don't underestimate the amount of heat you'll need.

Don't forget that large-ish parts will sink a lot of heat away from the join site.

Assume it's toxic cadmium silver solder unless you know for sure it's not --use a well-ventilated area.  I think it was supposed to be more-or-less banned, but some of it is still around.  I've got about 10 oz of it and although it will take another 70 years to use it up, I refuse to sell it to anyone.

One of the things I love about APS is that no mention of now-banned or restricted or just dangerous materials, chemicals, poisons, metals which are liquid at room temperature, etc is complete without the addendum "I got about (amount) of it back in the (garage/shed/basement)"

[230RN]

^ You're right, CNYCacher.

 I dunno why  I added it except for "color."  Amusing observation.

Most of the time official bannng of noxious stuff allows sale and use of existing stocks.  I'm not even really sure it was officially banned  --might have been voluntary.  I suppose I could research it later on a high speed connection on one of my long-overdue and well-deserved breaks.  No big deal either way as long as the place is well ventilated, though.

The coil of silver solder I have has a warning tag on it.  Picked it up at a garage sale, for only a couple of bucks.  The tag could easily have been lost in all the years it had been floating around.

Dunno why I added ^ except for "color." 

Terry, 230RN

[Nick1911]

My silver solder is recently purchased from an HVAC supplier.  I'm reasonably sure it's safe, however normal precautions apply.

As far as heat - I'd like to have an oxy-acetylene rig, but I'm making due with a Mapp/oxy setup.  The disposable bottles are expensive, and runtime is abysmally short, but it gets hot enough.

[Jim147]

So, your making your own metering system?

Are you making it adjustable?

Do you still have the original coil in that?

You can borrow my torches but I know I'm out of acetylene. I need to run by Arrow and swap it out the next time I'm in town.  Trying to get a hold of the BIL. He's much closer to you and I know he's not using his torches.

jim

[Nick1911]

So, your making your own metering system?

Are you making it adjustable?

Do you still have the original coil in that?

You can borrow my torches but I know I'm out of acetylene. I need to run by Arrow and swap it out the next time I'm in town.  Trying to get a hold of the BIL. He's much closer to you and I know he's not using his torches.

jim

Yea, I'm replacing the capillary tubes with 1/4" OD copper tubing; then I plan to plumb a TXV into the liquid line (and, well, suction) for metering. 

We'll see how it goes.  Cutting out the cap tubes has not been fun.

[280plus]

Jim147 and 280plus will love this, but I've taken the hacksaw to my A-Coil, and am machining some new bits to solder in.

AHHHHH!!! Runs from room...

 

You one tricky devil boy. Wish you'd showed us pix and ideas beforehand, we might have been able to reroute you to an easier fix. But that's ok, long as you're having fun.  

generally with cap tubes you need to nick them with a triangle file, then bend and break them off at that spot to get a clear path at the ends. If you're just cutting them out a nice pair of dykes/dikes (whatever) works fairly well. Too late for that now too I 'spose.

Are you using MAPP to melt the factory braze and disassemble? Yea, not hot enough, or just barely. That's why it's using so much fuel and taking so long. You need acetylene to put it back together. MAPP does a horrible job when trying to stick hi temp braze together and once something is brazed you cannot go back and use low temp silver solder over it so you have to rebraze. You can use low temp for the TXV stuff. If you don't make sure you wrap the TXV in a wet rag before you start brazing it in!

[280plus]

FYI in my world braze means high temp soldering and soldering means low temp. Factory A coils are brazed.

[Hawkmoon]

FYI in my world braze means high temp soldering and soldering means low temp. Factory A coils are brazed.

But true silver (or "hard") soldering IS a high-temperature process, which is why I have always seen it included in the brazing category. It's very different from soldering copper pipe in plumbing.

[280plus]

Right, and I'm not exactly sure which type he's talking about. I have to believe high temp.

[Nick1911]

Right, and I'm not exactly sure which type he's talking about. I have to believe high temp.

Yea.  It was recommended that I use acetylene because I'd need that much heat.  I was able to use oxy-map, though.

Propane doesn't even touch it.

[280plus]

Nope, it won't. I've never triex mapp/ox so hopefully that's hotter than mapp/air. Mapp is expensive too btw. 

[Nick1911]

Nope, it won't. I've never triex mapp/ox so hopefully that's hotter than mapp/air. Mapp is expensive too btw. 

So is the oxygen. 

http://www.homedepot.com/h_d1/N-5yc1vZ1xjl/R-202044702/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053
http://www.homedepot.com/h_d1/N-5yc1vZ1xjl/R-202044701/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

[Jim147]

Have you thought about a B tank Turbotorch setup? Acetylene/air setup.

I used to use one in the shop only had to lug one bottle around.

jim

Never mind. Looks like they run about $250.00 these days.

[280plus]

Yup, problem is these days (around here anyways) nobody will sell you ox/acet unless you have some kind of credentials. Too many idjits blowing themselves up or burning their houses down and (naturally) suing the distributor.  

yea, what jim said, if you can get someone to give it to you. I use a turbo torch. I used the little MC tanks for quite a while for the convenience but lately I notice my torch gets more guts out of the B tank. Try a welding supply. You'll have to buy the torch though.

[Jim147]

I look down in the shop later. Maybe I still have one running around here.

jim