Hard & $ilver soldering & brazing

Fittings, parrots, packing, tooling and so on.

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heynonny
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Hard & $ilver soldering & brazing

Post by heynonny »

What Ive learn'ed about 'silver' soldering over the years.
I'm not a welder or plumber by trade, all this just works for me.

Various terms are used for hard soldering or brazing, even several welding shops have used the term "silver solder" for solder/rod that dosent contain any silver at all. What they mean is that the rod has the same characteristics as silver solder without actually having any $ilver in it.
silver-rod.jpg
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In the silver-rod.jpg, various types are shewn, and labeled. The first is typically what is mostly sold at industrial plumbing supply houses, (where I prefer to do business) its whitesh and its
got thin copper plating on it, 1/8thX1/16, & about 18" long. Shop around!! There are 3 industrial shops locally (one net based but I can order O/L and pick up at their warehouse) however, one of the locals was HALF the price of the others,over the counter, so look around.
The second, you might find, if you are lucky, same alloy as the first, but, 1/8" square and 3'long, one stick goes a long way! Its not plated and ends up looking ugly after a time, steel wool cleans it up nicely, and is whitesh under the crud.
Third is real $ilver solder, not plated, silver tarnishes badly, lots of stuff react with it. (ie NEVER put rubber bands around $ilver ware, unless you like to polish silver)( I think its sulpher compounds in the rubber) Steel wool fixes that. note the 'buttery' color.
Next is silicon-bronze rod shewn is 1/16" rod, also refered to as copper-bronze and even as silver-bronze, by some, its not silver. It is copper electroplated to keep clean. It looks like the real silver solder, buttery yellow. This is the really neat stuff. If you have a tig welder or someone who is tig welding your project together, you, or they can braze copper 2 copper, SS 2 SS, and this is the best trick, copper to SS.
Lastly, (brass) brazing rod is shewn as an example.
silsol+tor.jpg
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silsol+tor shows the flux I like and, a roll of 56% silver solder, (1/16" wire) and my li'l oxy acet torch which easily brazes 3/4" copper pipe with excellent heat control. The flux is water based, and has flourine and other wierd stuff in it, tastes vile. It is water base for application, and dries and melts, (like glass when youre done and it cools), impurities float off in this liquid.
in'n'out.jpg
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in'n'out.jpg shows a 2" F copper sweat fitting tig brazed with silicon-bronze rod to a SS pressure cooker lid, (MY 1st still) not much to see outside, but the action was done inside, it is relatively smooth, no nooks or crannys for sludge to get into. I steel wooled part of the copper to show the slight difference in appearance of copper and braze. The discoloration is from a LOT of mash going through this thing, 6 qts at a time.
tig-t.JPG
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tig-t.jpg is my 'Thermal Arc 185' tig machine. Tig is the way to go!!
If you can gas weld (braze), you can pick up tig welding (brazing).
The biggest thing for me was learning NOT to lift the torch away when finishing a weld or lifting to control the heat. Its like learning to drive stick shift after 30 years of automatic transmissions. Plus you HAVE to get into a comfortable position to do a good job.
comes to mind This welder is an excellent ac-dc stick welder too.
Who can give the make and model of my workbench? On the bottom, make & model of the storage bench?? One should be easy.

Harbor Freight makes a few tig units mainly with al-u-minium windings, which mainly limit duty cycle, and copper takes fairly high current rating as its an excellent heat conducter.
Actually I use an oxy acet 'rosebud' tip on my torch and use propane instead of acetelyne, its cheaper, and with less heat energy, easier for me to control the heat. I had to buy a propane regulater tho.

What else? Oh yes the tig welder I bought through the company I work(ed) for, the welding supply business for the project gave me a discount on top of a complete package special price the were runnibg at the time. Dont be ashamed to ask for such savings, even if they only remotely apply, the worst they can say is no.
One problem with SS, especially cheap pots and lids, is there is a lot of crap in the SS alloy and too much heat will actually creat pits and sometimes tiny holes in the metal. Ive de-alloyed the metal and ended up with black stains which still showed up after sandblasting. Tig welding solves this nicely, though you still must have everything CLEAN.

Comments are welcome. Theres stuff that dos'nt come to mind right now, for better or worse, , , -hey-

Off topic here, a news letter I get from an organization I am in had an article 'The Parlance of Tudor Palaces' by Bill Plachy, about words about castles. One of which: , , ,"The 'buttery' was logically enough, a part of the royal kitchen. However, it had nothing to do with butter (all ourcontemporary bakery and restaurant names notwithstanding). In fact, it referred to "butts," as in casks of wine or spirits. The 'buttery' was the place where the booze was kept. Apparently anything alcoholic was the favorite target of theft, so only the most trusted of retainers could hold sway there. That worthy individual was called the "butler." fwiw

came to mind I was at recyclers and found a SS 10" round RV / camper sink, nice, heavy, wide flange, about 1-1/2" hole for drain, a crease (where the drain fitting/plumbers putty would go) you could use as a guide for enlarging to 2" or even 3" column, its very stiff, strong. It fits nicely in the end of a SS keg, check it out, , ,
  
 
 
       Oh,look!! Its a hole in the space-time contuum!!
punkin
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Re: Hard & $ilver soldering & brazing

Post by punkin »

Nice post.

I do have a couplea comments,

#1 Clean YOUR DAMN SHED UP!!

#2 I'm sorry to say it, cause i like your posts and look forward to your views, but unless you change that av, you are going on my ignore list. :(

Just not something i want to look at at 5 in the morning (when i spend most of my time here). :oops:
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Re: Hard & $ilver soldering & brazing

Post by Ayay »

:mrgreen: One is a Mercedes, the other looks like a bed but closer inspection there may be a Porshe or a Karman Ghia in there somewhere.
cornflakes...stripped and refluxed
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Re: Hard & $ilver soldering & brazing

Post by astrangebrew »

Interesting post. My brazing and welding skills are very rusty but I plan on working to improve that. Thanks for the tips.
My first guess was a '54 vette but on 2nd glance the headlight bulges look too far back. Ayay's speculation of a Karman Ghia looks right, I think I see a hint of the center ridge.
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Re: Hard & $ilver soldering & brazing

Post by violentblue »

still off topic, definatly not a Ghia, looks like an early 911 to me or possibly a late MGB
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Re: Hard & $ilver soldering & brazing

Post by punkin »

Can someone else let me know if that avatar disappears?










IJustCan'tHandleItPunkin
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heynonny
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Re: Hard & $ilver soldering & brazing

Post by heynonny »

Is this better?
  
 
 
       Oh,look!! Its a hole in the space-time contuum!!
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Re: Hard & $ilver soldering & brazing

Post by Hawke »

Much better heynonny. Sorry, but I was in Punkins camp on that as well.
It is the very things that we think we know, that keep us from learning what we should know.
Valved Reflux, 3"x54" Bok 'mini', 2 liebig based pots and the 'Blockhead' 60K btu propane heat
punkin
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Re: Hard & $ilver soldering & brazing

Post by punkin »

Welcome back to the land of the living, i'm glad to be able to share your insights for sure, heynonny.

I didn't want to dictate to you, just something i couldn't hack so i changed what i could.












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heynonny
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Re: Hard & $ilver soldering & brazing

Post by heynonny »

#1 Clean YOUR DAMN SHED UP!!
this is my '64 C cabriolet
porc.jpg
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the 170 merz
170.jpg
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-hey-

Why does mineral water that has trickled through mountains for centuries have a use by date?
  
 
 
       Oh,look!! Its a hole in the space-time contuum!!
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Re: Hard & $ilver soldering & brazing

Post by Ayay »

heynonny wrote: Why does mineral water that has trickled through mountains for centuries have a use by date?
The use by date is when the polyfukno's leaching from the plastic container become toxic.

Your investments look none the worse after serving as a work bench and a bed. Really cool - they will improve with age better than super or any other mianstream scam. As a teenager one of the teachers drove a Merc like yours and I earmarked it as one I would love to get, or the Citreon that looks similar. Never happened because '54 VW Bugs were cheaper, and the BMW R50, Triumph Tiger Cub, Honda CB450, Matchless650, Triumph V8, Mini Cooper... now I drive a Tarago van. That's why yours are extra valuable!

On topic: I had trouble brazing copper to stainless steel with the cheap silver brazing alloy. Silicon bronze may be the answer and I will have to look at TIG. Thanks for the good info.
Cheers!
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Re: Hard & $ilver soldering & brazing

Post by heynonny »

Got a 'Harbor Freight' sale ad in the mail yestdy. They have a 120 amp tig welder for about 300 bucks. They used to sell Italian made welders which were not too bad, but nowadaze everything seems to be made in cHINA (especially H.F. stuff), and I dont know how good that might be. They generally use aluminium wire in transformers which is OK, but limits the duty cycle. And copper, being the great heat conducter it is, needs a higher amp setting than one might realize, putting one in the 10% (or lower) duty cycle, , ,

Ayay, checkitout:
56vw.jpg
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its a '56 >sunroof<
-hey-
  
 
 
       Oh,look!! Its a hole in the space-time contuum!!
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Re: Hard & $ilver soldering & brazing

Post by Ayay »

I'll be looking at the local supplies of TIG soon. I think al windings will be OK because the unit will be lighter and I don't need a heavy duty cycle, except for tigging copper as you point out. The stick welder and the oxy torch has served me a long time but there's more to be had.

Your beetle has nice chains!
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Re: Hard & $ilver soldering & brazing

Post by CoopsOz »

Ayay wrote: The use by date is when the polyfukno's leaching from the plastic container become toxic
:lol: :lol: :lol: :lol:
It is most absurdly said, in popular language, of any man, that he is disguised in liquor; for, on the contrary, most men are disguised by sobriety. ~Thomas de Quincy, Confessions of an English Opium-Eater, 1856
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Re: Hard & $ilver soldering & brazing

Post by heynonny »

The question about centurys old water was rhetorical
-hey-
like : why do women have their mouths wide open when they apply mascara?
  
 
 
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Re: Hard & $ilver soldering & brazing

Post by snuffy »

I just did my first ever braze - brass to copper. 44% silver, paste flux with chlorides and fluorides, MAPP gas / air torch.

Holy crap you have to get things hot before it flows! I was looking a dull red and thinking Whiskey Tango Foxtrot? and then it got to liquidus temp and Kazango!

It's easier than soldering! I am lusting after an oxy torch now. That big MAPP gas flame is all over the place.
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Re: Hard & $ilver soldering & brazing

Post by snuffy »

Anybody got any tips on a pickle (acid or sumpin') to strip the oxide off copper after brazing?
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Re: Hard & $ilver soldering & brazing

Post by HookLine »

Yup, brazing is easier than soft soldering, which is quite a skill.

I soak the work in plain white vinegar. Works well, but can take 2-3 days to fully strip the crud off.

(BTW, soft tin based solders do not seem to like vinegar soaks, leaves a black coating on and around the joins. Only recommend it for cleaning up hard braze joints.)
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Re: Hard & $ilver soldering & brazing

Post by Ugly »

If you don't want to buy pickling solution make up a mix of flour paste with salt and vinegar and brush it on the pipe, I leave it till it starts getting that dehydrated look and take it off with a copper scrubber. As Sir Hook said, keep it off the soft tin solder where possible.

Tip for hard solder brazing, flux the joints, taping off area not to be fluxed before hand for neatness if you care (I use anti flux, same difference). If it's a round joint, wrap a single strand of the appropriate gauge braze around the connection point so it sits tight to the fitting lip. Heat the connection in a circular motion starting about a and inch and half- 2 inches away from the joint with oxy-acet gradually moving upwards around the pipe. The heat with suddenly hit and POP you will have the neatest looking hard silver braze joint on the planet. I sometimes use this method on soft solder if appearances count, you can also look into adjustable dual head torch bodies for oxy-acet or oxy propane to get two side of the pipe at once - provides much more even heat, faster neater job. They can be hard to find/expensive . Found mine in a box lot at the auction.

Never water cool it, just let it cool off on it's own.
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Re: Hard & $ilver soldering & brazing

Post by CoopsOz »

What vinegar does in three days can be done in 5 mins by using hydrochloric acid instead......I guess I'm impatient. :D
It is most absurdly said, in popular language, of any man, that he is disguised in liquor; for, on the contrary, most men are disguised by sobriety. ~Thomas de Quincy, Confessions of an English Opium-Eater, 1856
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Re: Hard & $ilver soldering & brazing

Post by Ayay »

What Ugly says, but I just wrote this and here it is:
Untreated copper oxides are quite tough, acid will make them easier to scrub off. Hot water will get the flux off, acid will dissolve the flux along with the copper oxides and mostly leave the oxides there in some other chemical state. I've used sulphuric, hydrochloric, nitric and glacial acetic acids and they all work. About 7-10% acid in water is safe to play with, but avoid skin contact and use rubber gloves and eyeglasses.

Sulphuric acid (aka muriatic acid) is battery acid and hydrochloric (aka spirits of salts) is concrete cleaner, easily got at about 30% strength. Glacial acetic acid (aka vinegar) is dangerous stuff when pure - the fumes will dissolve flesh and it is flammable! Nitric acid will keep going and dissolve the copper so best leave it out. Dry swimming pool acid is supposed to be a good alternative because it is safer but I haven't tried it on copper.

The dilute acid can be painted or sprayed repeatably on big items and small items can be soaked in it. Scrubbing with a wire brush or stainless pot scrubber with lots of rinsing will get to clean copper again.

When I apply a neutralizer such as bi-carb soda I get a yellow compound and it is just as hard to scrub and rince off as the acid compounds.
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Re: Hard & $ilver soldering & brazing

Post by HookLine »

Muriatic acid is hydrochloric acid.

One reason I prefer plain white vinegar is for safety. Doesn't matter much to me if it takes a day or three to do the job.

Anybody tried phosphoric acid for this application?
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Re: Hard & $ilver soldering & brazing

Post by Dnderhead »

" "Anybody tried phosphoric acid for this application?"
Recommeded on stainless
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Re: Hard & $ilver soldering & brazing

Post by snuffy »

Thanks guys.

The braze is 44% silver. It would have been impossible to keep the tolerances with solder. this is spraying phosphoric acid and then ScotchBrite and stainless steel brush results. It took three applications to cut through the oxide. I can't reach the inner areas, but they appear to have cleaned up pretty good.

I'm thinking of trying reverse electrolysis just because I want to (it's also supposed to be great for etching circuit boards without nasty ferric chloride.) the current issue of Make magazine has an article about it and how to deoxidize anything made of metal, but it doesn't talk about cleanup from braze or solder.

Image

Image

This is part of a coldfinger for a hybrid CM/VM head. I'll post the build log someplace when its done. It will require some explaining as to why I had to build it so funny looking. the target is to eat 1500W of vapor with it. it's approximately 1" x 6". According to the data I got from testing the other coldfingers, this ought to do it with headroom to spare -- IF I get a small enough deltaT over the funny looking slotted-cap thingys. I'm putting a backup condenser above it just in case it doesn't hit the target.

the goal of this particular exercise is VM with autoshutoff for the *heads* azeotrope. I dunno if it will work, but it's worth a shot.
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Re: Hard & $ilver soldering & brazing

Post by Husker »

Be careful. Reverse plating just might remove your solder joins.

I use it to strip gold plated items (pins, and jewelry). Solder 'might' drop off in the same manner, especially if it is silver (higher noble than copper).

The process I am talking about is 4.5 to 6v DC, 98% sulphuric acid with a touch of glycerin added. SS anode (or copper mesh bag anode for doing a batch of computer pins) trying to never to submerge the anode (just the gold plated item, but with copper bag, you have no choice), and poured lead cathode.

Not sure of the method you read about, but if it is the above listed (patented deplating) method, then beware, I think you might end up with problems.

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Re: Hard & $ilver soldering & brazing

Post by xx7777xx »

Wow, this is a great thread that I wish I would have read way sooner. This weekend I was trying to braise 2" SS ferrules to 2" copper with a Mapp/Oxygen torch and had the fight of my life. I ended up having to go over to a friends shop to use an acetylene torch to finish the job. I didn't think you could make this type of join with a tig. I might have to look into getting my hands on a tig...

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Re: Hard & $ilver soldering & brazing

Post by Ayay »

Husker I've had a similar experience with silver solder, left a piece of jewellery in the pickle (20% hot sulphuric acid) overnight and the solder was porous and crumbly. I think the zinc was eaten out.

Hookline, sulphuric acid = oil of vitriol....now I remember :oops: not that anyone uses that name nowdays.
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Re: Hard & $ilver soldering & brazing

Post by Ugly »

Where is everyone buying all this exotic acid? I can get some types of acids via dairy supply etc, but not others. I'm in Canuckistan, pointers appreciated.
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Re: Hard & $ilver soldering & brazing

Post by snuffy »

Phosphoric and muriatic are at most hardware stores. Phosphoric is used for rust removal and "pickling" metal before painting. The brand I get is Jasco Metal Prep (make that Jasco Metal Etch) - in the paint department. Muriatic acid is used for cleaning brick, concrete and tile. It's also used in swimming pools for adjusting the chlorine pH. sulfuric is battery acid. It can also be found in some hardware stores as super-duper drain cleaner. Dunno where you get glacial acetic acid. I used to get it from the pharmacy for removing warts. It's called glacial because it's sort of syrupy. I've had a quart of phosphoric around for years and it's still over half full. Doesn't take much.
Last edited by snuffy on Mon Mar 09, 2009 11:31 am, edited 1 time in total.
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Re: Hard & $ilver soldering & brazing

Post by Dnderhead »

acetic acid= white vinegar also used in photo developing
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