Soldering Stainless

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Selby
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Soldering Stainless

Post by Selby »

Does anyone know the secret of joining stainless to stainless? Itried to silver solder as normal but it went like water on a cabbage & wouldn't stick .Should I use acid in place of flux, get compatable solder etc.? It's too thin to electric weld. - Thanks Selby.
rad14701
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Re: Soldering Stainless

Post by rad14701 »

Try Googling "soldering stainless" and you'll find plenty of information... See Soft Soldering HERE as well as THIS PAGE for starters... Both mention phosphoric and/or hydrochloric (muriatic) acid... I recall using an acid based paste years ago but I'm not sure if it's still available...
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Re: Soldering Stainless

Post by Dnderhead »

Stainless can be welded even if thin but not all have equipment (tig best for thin or mig if your careful) to solder you should have a aggressive flux as phosphoric acid
or zinc chloride , rough surfaces with coarse sandpaper apply flux only where you want to solder. stainless "skins" over almost instantly.
(aluminium does this also) they do make "kits" of, flux/ solder to do stainless. mite have to go to a welder supply to fiend it.
Selby
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Re: Soldering Stainless

Post by Selby »

Thanks Rad & Dndr. Almost as soon as I had finished posting it dawned on me to search Engineer/ Metallurgist John Palmer's excellent book "How To Brew"- formerly free on the Net & shore 'nuff in the chapter titled Soldering Brazing & Welding John suggested the metal had to be "wetted" with HCL or zinc Chlorideto prevent the solder balling. Put me in mind of trying to wet a duck in hot water for plucking without adding wetting detergent! So I'll give it a try. Cheers.
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Re: Soldering Stainless

Post by myles »

I have found there is some good info on http://www.cupalloys.co.uk
They describe soldering anything to anything and have specialist solders and fluxes. Have used their stuff and it works but it is really easy to overheat the stainless. Have only managed to get it to work with MAP gas. Don't have access to mig or tig but butane and propane just wont do it.
Good luck.
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Re: Soldering Stainless

Post by heynonny »

A little more general info:
http://www.realbeer.com/jjpalmer/Welding.txt
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Hack
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Re: Soldering Stainless

Post by Hack »

myles wrote:... but butane and propane just wont do it.
Propane will work. I've used it. It might not be the easiest. I don't know. It's all I had. That being said, I used a flux that was specified for stainless and smelled like acid. I found I had to scuff it up real good with sandpaper. Then I tinned the mating surfaces with solder before joining them using my electric soldering iron. Lastly I used the propane torch to heat the joints and filled with solder. The problem with the stainless is it doesn't conduct the heat well, so it will scorch the spot you are trying to work easily while you are trying to get the heat spread out. Don't put the heat too close and keep it moving.

That's the limited extent of my advice. :D
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Tater
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Re: Soldering Stainless

Post by Tater »

I use a coated solder that I get from A ac supply store .It will solder copper to ss. SS to ss and either to brass.
I use a pot still.Sometimes with a thumper
Selby
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Re: Soldering Stainless

Post by Selby »

Thanks fellas.(Guys) , I ended up getting the job done as easy as silver soldering copper after the local welding supplier pointed me in the right direction. For anyone interested in silver soldering .020" thin kitchen grade stainless, here's the specs. Flux:- EZI - WELD 602 Flux containing Fluorides 34% W/W, Borates 34% W/W. Solder:- 60% silver. Applicator:- Map Gas torch (with care)- no iron needed. Of course clean off all grease & wash in soapy water or detergent & rinse well beforehand. Wash well after.
xx7777xx
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Re: Soldering Stainless

Post by xx7777xx »

I have recently build a VM rig with intentions to be able to convert it to a pot setup.
http://s410.photobucket.com/albums/pp18 ... cture1.jpg

I had a hell of a time getting the 2" SS ferrule (not pictured) silver soldered to my bottom column to connect to my boiler. I have two more ferrules and a clamp that I would like to add in about 12" below the head but I'm now a little hesitant to cut my column b/c silver soldering was such a pain.

I used a MAPP torch with Sta-Brite silver solder:
http://www.philshobbyshop.com/tek9.asp? ... jmopcmdrr0

I'm reasonably handy with soldering copper, but it took me almost an hour to get the SS ferrule tinned, as the solder just doesn't like to stick the stainless. I've seen several people who have made these joins, so I'm guessing there must be a fairly easy way to accomplish it. I've read several articles about different tactics, but was hoping to get the definitive method for how to do this. I've started a Supplies and Procedures list below, but obviously need some input on the procedures :-).

Supplies
Solder - Start with a quality silver solder & flux. Can anyone recommend an online store and product?
Flux - I used the flux that came with the silver solder mentioned above. Any recommendations?
Torch Fuel - I have tried MAPP, Propane, MAPP & Oxegen. I seem to have the best luck with MAPP
Torch Tip - I've read that using a soldering iron tip as opposed to open flame is important. I don't have one to try but if this is the case I will definitely get one.

Procedures
Clean - Clean both the SS and copper meticulously
Flux Application -
Heating -
Solder Application -
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new_moonshiner
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Re: Soldering Stainless

Post by new_moonshiner »

tater wrote:I use a coated solder that I get from A ac supply store .It will solder copper to ss. SS to ss and either to brass.
would that be the orange colored ones by chance tater ?
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Tater
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Re: Soldering Stainless

Post by Tater »

I use the pink ones there like 9 bucks a stick but once ya get some of the flux heated you can use the 15 percent silver ,Thats what I used to solder my worm to ss keg I use for condenser.Think I posted its brand name on another post a year or so ago.
I use a pot still.Sometimes with a thumper
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Re: Soldering Stainless

Post by WalkingWolf »

Would you happen to have the name and where to get some? I'm in the same position as xx7777xx and having a hell-uv-a time trying to "tin" the stainless :? . Any other tips been discovered for this process?

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Tater
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Re: Soldering Stainless

Post by Tater »

Ive bought them or solder like it in any refrigeration or heating supply shop as well as most welding supply's
I use a pot still.Sometimes with a thumper
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Re: Soldering Stainless

Post by new_moonshiner »

http://www.airgas.com/browse/product.as ... svl=144145" onclick="window.open(this.href);return false;" rel="nofollow
WalkingWolf
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Re: Soldering Stainless

Post by WalkingWolf »

thanks NM.
myles
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Re: Soldering Stainless

Post by myles »

Would like to hear how you got on. Every time I have tried I got a good join with the silver solder and specia flux, but I also overheated the stainless. It will then rust. Well that is a generalisation - it depends on the type and grade of stainless.

Keep in touch. :D
xx7777xx
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Re: Soldering Stainless

Post by xx7777xx »

WalkingWolf wrote:Would you happen to have the name and where to get some? I'm in the same position as xx7777xx and having a hell-uv-a time trying to "tin" the stainless :? . Any other tips been discovered for this process?

WalkingWolf
I ended up taking my parts over to my buddy's shop where he braised it for me with an oxy torch (I don't actually know exactly what materials he used). It seemed to me that I just couldn't get the 2'' copper & stainless hot enough with MAPP. And as anyone with a do-it-yourself MAPP torch knows those oxygen tanks are not cheap and do not last long at all.

x7
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WalkingWolf
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Re: Soldering Stainless

Post by WalkingWolf »

Well I tried the brazing rods ($30.00/3 rods) and burnt the SS before the rods would start to flow. Tried the Silver solder with Stay-Silv but no luck. I made an easy flange on a 3" with #4 wire. Will need a little reshaping to work with a tri-clamp. Made two easy flanges on 3" with #6 wire and they work in a tri-clamp without any reshaping. This was by far the easiest method that I have attempted. I will have several unused SS ferrules of various sizes left over when this build is complete.

I am posting this follow up as a benefit to those just getting started and, like myself, having only recently begun soldering with no real additional metal working knowledge/skill. The easy flange is a do-able and strong connection.

thanks to all for the guidance and feedback to those of us just starting out.

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goinbroke2
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Re: Soldering Stainless

Post by goinbroke2 »

WW, did you get my PM about stainless soldering? I was going through cleaning stuff up and saw nothing in my sent file.
Numerous 57L kegs, some propane, one 220v electric with stilldragon controller. Keggle for all-Grain, two pot still tops for whisky, a 3" reflux with deflag for vodka. Coming up, a 4" perf plate column. Life is short, make whisky and drag race!
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Re: Soldering Stainless

Post by rednose »

You can soft solder SS if you copper plate it before.

You only need a cellular charger, copper sulfate what you can get in pool shops an acid and a piece of copper.

I was reading about that somewhere in a brewing site two weeks or so ago.

I use that often to copper fittings.

I'll post the link if I get back to there.

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Re: Soldering Stainless

Post by HookLine »

I think Snuffy did some stuff about copper plating stainless.
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Re: Soldering Stainless

Post by D-Weasel »

Selby wrote: like water on a cabbage

I just came here to say I love this phrase and will be using it from now on. Thank you.
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