Silver solder question.

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Wyowill
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Silver solder question.

Post by Wyowill »

I would appreciate it you all could give me some idea of how much silver solder be used on a 4" Raritan boiler. I know there are a lot of variables, just want a general idea. :shock:
Thanks.
Will
hoppercar
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Re: Silver solder question.

Post by hoppercar »

How big of wire are you planning on using?..1/32......1/16 th ???......there's really no way to tell ?....some people make a neat joint....others blob it in there like painting a barn.....just get a one pound roll, and go for it
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Fender
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Re: Silver solder question.

Post by Fender »

You can reduce the quantity of solder needed by using a “resist” to prevent the solder from flowing where it isn’t wanted. There are commercial products for this purpose, which are painted on after the work pieces have been cleaned and prepped for soldering. The resist forms a barrier to prevent the solder from flowing past the barrier. I have not tried this myself, but have read that a wide pencil mark or marking pen mark will also form a barrier.
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Bill Shields
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Re: Silver solder question.

Post by Bill Shields »

About $200 worth depending on the market price of solder.

It is all in the technique of knowing what you are doing to get the job done with minimal solder.

If you have never built a copper boiler, best you get someone who has been there done that to help you.

This from someone who has "been there done that" a dozen times in the past 45 years..including 2 Raritan boilers
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Wyowill
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Re: Silver solder question.

Post by Wyowill »

Hmmm... A pound roll. Would that be a Troy pound or Avoirdupois pound. :lol:
Seems like everyone is afraid to tell how much excess silver they used. :shock:
Just curious, I'm not judging.
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Bill Shields
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Re: Silver solder question.

Post by Bill Shields »

not afraid...just really do not know.

very few of our 'weigh in' at the beginning and end of a boiler job. I just make sure that I have enough on hand to keep going until I finish..nothing worse than to run out between heats...

if you have never built a boiler, doubt you could build one with twice the amount of solder I use, and guarantee that I cannot build a boiler with as little as GWR Driver uses...

you always have little bits and pieces laying around when finished, need longer pieces to hold on to when 'reaching in'....it is not an exact science as would be when soldering together 100 identical candlesticks in an automated process.

I would be more concerned about the cost of propane, oxygen and acetylene (and copper). No idea what $$$ of copper is these days, but cannot imagine that it is cheap.
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gwrdriver
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Re: Silver solder question.

Post by gwrdriver »

Shields is being too kind, I've had conditions which absorbed more solder than I expected so I let it take what it wanted, only to discover the excess pooled somewhere it wasn't needed. It happens. As Bill says, it's not possible to estimate with any accuracy how much a given builder will use, although the smaller the boiler the more likely you are to be close. I've never built a Raritan boiler so I can't make a guess. Most I've built have been larger, or smaller, so those won't offer much help.

I'll tell you what you should do though, use STICK solder. If "Stick" ends up being a bunch of wire, then cut it to 12"-16" lengths and straighten it. The best thing would be to buy your solder in 1/8" flat sticks or rods and here's why. When you've got the "Lump" up to soldering temperature things happen pretty fast and you'll eventually need to put solder exactly where and when it's needed, and sometimes in surprising quantity. In those situations stick is much easier to direct than a thin wire. Unless you have an assistant doing it as you go, you cannot pause the heat while you unroll and straighten more wire. Also, should you go in that direction, you will be astonished at how quickly even a well-made joint will suck up 1/16" wire.

Strong suggestion #2 is Don't Skimp on Flux. Flux is cheap, copper isn't. I use mostly white paste flux, others on here swear by black flux. Either way slather it on good because adding more in the middle of a heat is rarely helpful and if it's a flux-deficient closed joint, usually never helpful.
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Bill Shields
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Re: Silver solder question.

Post by Bill Shields »

IF YOU WANT an absolute minimum amount you will use:

calculate the linear inches of joint(s) that you have...all holes, all edges, etc:

figure you will be using 1/16" stick...1" of stick to 1" of joint

calculate cost from inches of 1/16" stick you will purchase...

then double it....
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Bill Shields
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Re: Silver solder question.

Post by Bill Shields »

At old prices, the last Raritan size boiler I built had $1000 worth of copper, bronze and silver solder in it.

No idea what it would cost today...except MORE
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Greg_Lewis
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Re: Silver solder question.

Post by Greg_Lewis »

Just a slight aside: some books on model boilers that might be of interest. I haven't looked at these in terms of how valid they are as I'm not building a copper boiler, but these do go into detail. Copies might be found on Ebay.
Model Locomotive Boilers Their Design and Construction, by Martin Evans
Model Boilers & Boilermaking, by K. N . Harris
The Live Steam Book, by LBSC
Model Steam Locomotives, by Henry Greenly
Model and Miniature Locomotive Construction by Stan Bray
The latter is the best produced with large pages and quality photos. All these are of U.K. origin and might still be available from there.

Also, Kozo Hiraoka's books detail copper boiler construction. They are available from the publisher of Live Steam magazine, Village Press.
Greg Lewis, Prop.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.
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Bill Shields
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Re: Silver solder question.

Post by Bill Shields »

Good books all.

I do not always agree with Kozo's boiler design philosophy, but his techniques for soldering are very insightful.
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ALCOSTEAM
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Re: Silver solder question.

Post by ALCOSTEAM »

I recently bought a 1lb roll of specialized refrigeration silver solder and it was just over 80 bucks. If you get a price on anything copper the price or quote is only good for the day and some places only good till you hang up the phone.

There is no way I would build a copper boiler as even a small one you are going to have a fortune in materials. Steel right now is high but with some looking around you might find a bargain on some drops, copper there are no drops just high dollar scrap. Just the copper tubes to roll into an otherwise steel boiler will make you poor.

The other comment I will make is you could be the best silver solder person but your assembly technique and order of assembly on a copper boiler is highly critical. Many times you don't or can't achieve a successful do over with copper.
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