How to solder (beginners guide)

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BigSwede
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Re: Howto solder (beginners guide)

Post by BigSwede »

I found an interesting tutorial video about soldering stainless steel. He talks about making flux among other things. He's a bit verbose, but there is some good information here. 30 minutes long. Skip to at least 7:00 unless you want an intro on basic flux ingredients.

http://www.instructables.com/id/Solderi ... ow-To-Mak/

One point he emphasizes, and I agree completely, is the act of tinning the stainless, getting through that inhibiting oxide layer, and getting some solder onto the SS part, BEFORE attempting to join it with copper.

If you simply place a ferrule onto a copper pipe, slather on the flux, and have at it with a torch, it's probably not going to work well.

I believe the key to SS soft soldering is the flux. Once we get the solder onto the stainless, get it to bite, then we KNOW we can join it to copper, knowing how easy it is to get solder subsequently flowing onto the Cu.
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Re: Howto solder (beginners guide)

Post by muddog »

BigSwede wrote:I found an interesting tutorial video about soldering stainless steel. He talks about making flux among other things. He's a bit verbose, but there is some good information here. 30 minutes long. Skip to at least 7:00 unless you want an intro on basic flux ingredients.

http://www.instructables.com/id/Solderi ... ow-To-Mak/

One point he emphasizes, and I agree completely, is the act of tinning the stainless, getting through that inhibiting oxide layer, and getting some solder onto the SS part, BEFORE attempting to join it with copper.

If you simply place a ferrule onto a copper pipe, slather on the flux, and have at it with a torch, it's probably not going to work well.

I believe the key to SS soft soldering is the flux. Once we get the solder onto the stainless, get it to bite, then we KNOW we can join it to copper, knowing how easy it is to get solder subsequently flowing onto the Cu.
Finally after 151 posts we're going to talk about tinning. I'm am newbie to this forum, but not to shinnin or beer making . This is one point that has been completely missed . If you want to take a moderately difficult task and make it relativity simple, then learn to tin stainless.
it's very simple. clean your pieces , I sand mine, flux em, heat em, flux so more , put solder to it ,if it doesn't stick, flux some more. make sure you have solder all the way around your piece.
You have your joint all cleaned and fluxed, put the heat to it and solder and the solder just runs everywhere, it's not like copper which loves to suck up solder. maybe you didn't clean well enough or you got your flux to hot and burned it. now it has to come apart to be
re cleaned and now you are going to try again and hope for the best.
Once you have it tinned, you know it's going to take solder. watching the tinning while heating is also about the best indicator that you have the proper heat on both pieces. as you are heating watch the tinning, to me it looks like it starting to sweat, then it will get shiny, it has now come to temperature. now is the time to add more solder, if need be ,I've had joints come together perfectly with just tinning.
I drilled a keg for a tri clamp ferrule, it fit snug like it was supposed to,but the hole was ragged so I cleaned it up with my dremel. set the ferrule in the hole and it fell thru to the flange, that was good. now I had to figure a way to keep the ferrule in place. had a drink or 10, I lost count. but it finally came to me to tin the ferrule to make it fit snug in the hole. once I tinned the ferrule I had so much fun doin that , I decided to tin around the hole on the keg. set the ferrule back in the hole ,gave it a little tap to set it, put the heat to it , watched the solder get shiny and all of a sudden it just all sucked together added a little more to form a shoulder and was done. After that I will not solder stainless without tinning first.
I know how frustrating it can be to solder stainless. this technique will take most of that out. it is fun to me now to watch it come together instead of running all over the place.whereas it used to be a chore to solder stainless. you'll save solder as well.
try it, you'll like it. Muddog
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Re: Howto solder (beginners guide)

Post by PhatFil »

Im still having a bit of trouble with my soldering.. while my skills have improved a little after digesting the info ive found here, im now prepping for fix #5 on one aspect of my build.

I do find it a bit tricky needing 3 hands i for the torch and 1 for the solder and 1 for the flux brush to clean off the burn when overheated..

I am removing heat as soon as i see any melting occur and applying it back with a wave on/off again if needed. and am trying to apply heat indirectly to the joints..(tricky with so much going on in a small area..)


I may have overlooked the crucial basic tip in my reading if so PLEASE point me to it.. Cheers..

im attempting to build a boka 2" column, however it struck me as a good idea to make a small seperate plate/collection section flanged at each end to attach to the packed column and condensor section,

my problem i think is down to overheating the work area and solder melting out of the less than 1mm gaps between the plates ive inserted and the 2" tube body.. so i have been wrapping all areas i want to keep intact with wet rags, i have wire jigs to keep both temp probe and exit tubes in place with solder melting.. and am wiping the work area with flux when it appears to have been overheated while flame off and adding more solder.. but when i clean back i find gaps!!! aarrgghhhhh!!!!!!!

I am cleaning back with citric acid baths and working the gap with a thin wedge needle file before applying flux for resoldering???

solder goes everywhere but where i want it to go......
bad solder 1.JPG
ive been using a map capable torch with propane fuel, lo-lac? flux and lead free solder..

One thing i noticed with the 2" end feed fittings i used for the pot head aspect of my project is that they needed way more solder than the suggested 2" -2 1/2" length, so much so I was concerened about the possible volume of solder perhaps falling thru the join into the tube interior however when inspected no drip down internally was visible?? :crazy:
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Re: Howto solder (beginners guide)

Post by BigSwede »

Some thoughts, Phat... Obviously not being there and not being able to see how you solder, it's hard to give sound advice. But I'll take a stab at it! ;)

First, materials. There's a reason there are soooo many solders and fluxes out there... there are formula variations that give them different characteristics, for different materials. My guess is you have a standard lead-free plumbing solder of maybe 96% tin (Sn) and 4% Antimony (Sb). This is a typical all-around solder and works, I would say, just "OK" but nothing that makes me enthusiastic for it. To me, it blobs far too much does not thin and flow how I'd want it.

If you can find some - I had to order it - look for a true silver-bearing solder of at least 3%, preferably 4%. There's a thing going on these days where they sell "silver-bearing solder" that is 96 tin, 3.9 antimony, and a lousy 0.1% silver. Not true soft silver solder in my opinion. I use a 4% silver 96% tin solder, and the difference is dramatic. There's a reason such an expensive material (silver) is put in solder, it improves performance in a number of ways. The one pound roll I found on line was about $55 U.S. Plus, I'm not a fan of hot ethanol and antimony in contact. :sick:

Flux - Try a good water-thin liquid flux if you don't have it yet. Most plumbing fluxes are a greasy mess, don't really work all that well IMO, and are hard to clean up afterwards. Again, this may be something you have to order, but it's worth it. You can make a good liquid flux using muriatic acid, HCl pool acid, diluted with water. Fluxes designed to soft-solder stainless steel are particularly potent, but expensive. They work wonderfully well on copper. Because they are so thin, you may need to figure out a way to deliver the flux. I use a little squeeze bottle with a blunt stainless hypodermic on the end. Looks like this:

Image

But if you have neither fancy solders or fluxes, what you have will still work if the copper is properly cleaned. It is very common to under-prepare the copper, give it a few swipes with steel wool or similar. Don't use steel wool to prep, it contains a lot of oil. Look for a thing we call in the USA a "scotch-brite" pad. Comes in different grits or grades... medium is good.

Image

Clean the living heck out of the pieces to be joined, be generous with the flux, and go for it. From what you described, it sounds like your technique is good. Heat the copper away from the joint, let the heat flow to the joint. The flux will sizzle; remove the heat, apply a touch of solder. No melt, keep the heat coming, but as you approach the melt temp, slow the rate of heat increase down a bit. We don't want to park the torch head on the joint, it'll overheat in seconds. The trick or art to it is to get the joint to temperature, then keep it there but no higher. Watch the solder itself that's applied; as it solidifies, wave a bit more heat, but just a little, to keep it molten. With big copper, it can absorb a LOT of heat and keep the joint liquid for 30 seconds or more.

Having a cotton swatch on hand with some flux on it can be used to "flick" away molten solder from places where you don't want it, and also smooth out areas.

As far as keeping already-soldered parts together, it can be very tricky, and a lot of it is the order that you put parts together. For example, let's say you have a 1 foot two inch Cu tube, and you want a stainless ferrule on one end, and two slant plates inside. The order of assembly would be ferrule first, then plates. The ferrule will need MUCH more heat, which as you've seen would loosen the slant plates. You may have to disassemble, clean, then reassemble in the correct order. Wetted rags do work, but too many can interfere with heating the joint you WANT to solder.

Practice, practice. No one has a ton of 3" copper lying around for practice, but a handful of 1" Cu fittings and a piece of 1" Cu pipe will provide for a lot of practice. Solder a joint, cut it off, do another. Or build something, like a parrot or a little liebig condenser that won't hurt too much, cost-wise, if it gets messed up.

Good luck, HTH
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Re: Howto solder (beginners guide)

Post by PhatFil »

Cheers BigSweede, Yes the flux is a greasy paste, and the solder is a 96%tin 4% antonimy job..



I do have some harris stayclean liquid flux and 8% silver solder( cheers ebay) that i have used for adding SS ferrules to the packing column, and centre ring sections.. and those did fix easier, tho i have yet to test em and the ring of solder i wrapped round as per many threads in here melted and fell off rather than getting sucked into the joint, tho a quick dap of more solder was soon sucked in ok..

No light left today so will attack tomorrow with the silver solder and flux, no scotchbrite pads, but a few bits of wet n dry and the scrubby backs of kitchen sponges;)

thanks again..
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Re: Howto solder (beginners guide)

Post by Bob Loblaw »

Plus, I'm not a fan of hot ethanol and antimony in contact. :sick:
I'm curious what your basis is for this statement. I've seen people suggest silver> antimony before, so I did a a little bit of research. Everything I found suggested that there are far more toxicity issues with silver than there are with antimony. One study even suggested that antimony had fewer toxicity issues than Copper! Curious what you've seen? It would be good to have a solid fact base given how much solder is consumed by forum members here!

http://homedistiller.org/forum/viewtopi ... 0#p7150655
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Re: Howto solder (beginners guide)

Post by BigSwede »

I prefer silver mainly because it's a better solder. If antimony was better, I'd probably use it instead. But if equivalent, I think I'd still prefer silver.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3037053/
Antimony toxicity occurs either due to occupational exposure or during therapy. Occupational exposure may cause respiratory irritation, pneumoconiosis, antimony spots on the skin and gastrointestinal symptoms. In addition antimony trioxide is possibly carcinogenic to humans.
Antimony and its salts have been used as pretty potent medicines for centuries. The Everlasting Pill is a good one!

http://en.wikipedia.org/wiki/Antimony_pill

And the Antimony cup, when used with wine, was apparently an awesome digestive purge from both ends.
An antimonial cup was a small half-pint mug or cup cast in antimony popular in Europe during the 17th and 18th centuries. They were also known under the names "pocula emetica," "calices vomitorii," or "emetic cups", as wine that was kept in one for a 24 hour period gained an emetic or laxative quality. The tartaric acid in the wine acted upon the metal cup and formed tartarised antimony.
But silver and copper can also be toxic. So the answer is, no, I have zero hard evidence, it's just a gut feeling. I think the human body can tolerate silver and its salts better than antimony. Silver utensils have been used forever, little "gentleman's flasks" full of hard liquor are often sterling, so I guess that makes me feel better. :wink:

In another thread I'm pitching the use of the new "lead-free" brass, so I guess I need to become consistent. I have no doubt that Sn/Sb solder is fine for what we do.
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Re: Howto solder (beginners guide)

Post by PhatFil »

Cheers BigSwede, the liquid flux did the job for me, thanks...

progressed to a column build and vapor leak test ;)

only problem now is how to remove the blobs of excess solder too close to my plates for aggressive tooling or filling, might be a few long evenings with the needle files...
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Re: Howto solder (beginners guide)

Post by crazyk78 »

Try and use a soldering iron
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Re: Howto solder (beginners guide)

Post by PhatFil »

Cheers Husker, i will try n borrow a bigger one than my didy 15w electronics iron..
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Re: Howto solder (beginners guide)

Post by BigSwede »

New solder guys! I've owned probably a dozen propane and mapp gas torches over the years. I thought I had a really nice big propane torch that would be fine for heating and soldering 2" and up with no problem. But I found myself often using a second torch to get the heat up to where I wanted it.

I came very close to dropping $240 U.S. or so on an air/acetylene torch. These put out a lot of BTU's and would work great, but you have to add the cost of the torch to the purchase of a new acetylene bottle to get going, and it was going to be pricey.

In a last attempt to avoid this, I tried a new "professional" grade of propane/mapp torch, the Bernz-o-matic TS8000.

Image

This thing is incredible. Roars like a little jet engine. Even with propane, it brings an assembly up to soldering heat in 1/3 of the time even my big old propane "plumber's torch" would do. Mapp gas makes it even better. The combo of torch plus a bottle of mapp gas is about $50 in the USA. And it has a flame adjust valve, unlike its lesser brothers in the Bernz line.

If someone is looking for a good mapp or propane torch that will probably be the last one they'll ever buy, or want to upgrade, this is it. I am very happy with this torch. Best one I've ever used.
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Re: Howto solder (beginners guide)

Post by Scribbler »

Can anyone here add any tips regarding muriatic acid as a flux? (I actually HAVE two jugs of it and was startled/pleased to discover it works as a flux... So I'm hoping to put it to use... But this stuff turns concrete into pudding, so I'd like to get a bit better of a handle on it mentally before physically trying it out...) some of my grey areas are:

1). Application: apply to pieces, tin them, then solder them.
-but what about slip-in fittings where tinning (say, the inside of a copper tube, and the outside of a SS flange) might make slipping them together impossible? Just run a bead of muriatic acid around the seam? Wet both parts with acid, then fit them together?

B). strength: I recall reading a 15% dilution... Is that:
15ACID : 85H2O Or 85ACID : 15H2O?
Why not just use it full strength right out of the bottle?

III). Applicator test: I'd like to use a syringe and needle to apply, but I don't want it to start dissolving the syringe, contaminating the joint, not work properly, melt and spill in my hands, etc... I'm thinking I might take a glass jar, drop the syringe pieces in, fill with acid to cover needle, and leave it sit on top of my fridge overnight. Inspect in the morning. If no corrosion, then it's good to go? Is this a reasonable test?

4). Flashing off: acid goes on wet... Parts are still wet when heat is applied. I'm thinking the whole thing will be dry before I get the solder anywhere near the joint... How long do you have for good soldering before you have to stop, let the piece cool, clean and sand it, re flux and try again? Or even if tinning a large SS fitting... The other side of the tube might be dry of flux by the time you get there...

Any tips would be awwwwwwwSOME!!
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Re: Howto solder (beginners guide)

Post by PhatFil »

far from expert, just a surprised (how easy it can be) novice here ;)

a glass syringe? you should pick one up for about a fiver ??10usd?? tho i have used a polypropylene bottle with a stainless steel needle ala e ciggy topping up to deliver the liquid flux i use, just be carfull you dont suck any solder back up the needle when you release the application squeeze like i have done ;)

when soldering an endfeed SS 64mm flange (2" triclamp) to 54mm copper tube the gap between fittings is enough to accommodate a lightly tinned flange fitting, and tinnimg heavily isnt very easy as the SS fitting holds temps a lot longer than the copper.

you really need to work the SS surface with a file or emery cloth prior to tinning to aid the process. it takes a lot more elbow grease than cleaning up the copper aspect of the joint.

sounds like you should experiment, if it goes wrong solder is soft and fairly easy to file off again if needed ;)
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Re: Howto solder (beginners guide)

Post by BigSwede »

Scribbler, HCl straight from the bottle, pool acid, is typically 32%... I've worked with this stuff for decades as a chemist. As far as acids go, it's pretty benign. I once poured concentrated HCl all over my hands thinking it was a water jug. Saw the concrete foaming at my feet, ran to rinse my hands, zero problems. But don't do that! If it had been hydrofluoric acid, I'd be dead, nitric or sulfuric, bad injury.

HCl won't touch glass, plastic, stainless steel. Etches concrete, obviously. Feel free to load plastic vet syringes with SS needles as needed.

For flux, and I'm basing this on an educated guess, I'd try this... find some zinc first. Galvanized roof nails is a good choice. Pour maybe 500ml of concentrated acid into a glass jar. Add a handful of nails, say 30 galvanized roof nails. Watch as the acid eats the zinc right off the nails. When it stops bubbling, decant (leave the nails behind) into another jar. Dilute this 5:1, so dilute 1 cup acid with 5 cups water. None of this is critical. Add the acid to the water, slowly. You've just made zinc chloride / HCl flux for pennies.

There's your flux. Beware, HCl will rust any nice steel tool within a 10 foot radius just from the fumes.

When you apply it, you should see the metal brighten. If it doesn't, make it stronger. If it seems too potent, dilute it. Try some experiments. It'll work.

Edit: Apparently HCl is not recommended for stainless. I would never try soldering stainless anyhow with a home made flux. A real flux for stainless will have phosphoric acid and particularly fluorides. The latter are what really make it work well.
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Re: Howto solder (beginners guide)

Post by Scribbler »

Thanks for the reply. Sorry to infringe so much on you expertise! Could you clear one thing up regarding your edit,

Does your edit mean: don't use muriatic acid but the galvanized nails procedure is ok.


Or does your edit mean: "dont even do the galvanized nails trick on as, but on copper it is worth a shot"

? Thx!!
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Re: Howto solder (beginners guide)

Post by badbird »

Edit: Apparently HCl is not recommended for stainless. I would never try soldering stainless anyhow with a home made flux. A real flux for stainless will have phosphoric acid and particularly fluorides. The latter are what really make it work well.
BigSweed, I have always found HCL to be quite effective flux for soldering brass / copper to stainless using Sn/Cu solder. As per previous posts just clean well, tin and don't over heat.
Are you saying there are corrosion or other issues using HCL with stainless or just that the fluoride fluxes are more effective?
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Re: Howto solder (beginners guide)

Post by bearriver »

BigSwede wrote:New solder guys! I've owned probably a dozen propane and mapp gas torches over the years. I thought I had a really nice big propane torch that would be fine for heating and soldering 2" and up with no problem. But I found myself often using a second torch to get the heat up to where I wanted it.

I came very close to dropping $240 U.S. or so on an air/acetylene torch. These put out a lot of BTU's and would work great, but you have to add the cost of the torch to the purchase of a new acetylene bottle to get going, and it was going to be pricey.

In a last attempt to avoid this, I tried a new "professional" grade of propane/mapp torch, the Bernz-o-matic TS8000.

This thing is incredible. Roars like a little jet engine. Even with propane, it brings an assembly up to soldering heat in 1/3 of the time even my big old propane "plumber's torch" would do. Mapp gas makes it even better. The combo of torch plus a bottle of mapp gas is about $50 in the USA. And it has a flame adjust valve, unlike its lesser brothers in the Bernz line.

If someone is looking for a good mapp or propane torch that will probably be the last one they'll ever buy, or want to upgrade, this is it. I am very happy with this torch. Best one I've ever used.
I second this opinion. I have the same one and have soldered my 3" pipe quickly and effectively.
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Re: Howto solder (beginners guide)

Post by Scribbler »

I've only got a cheapo propane torch. But my father in law has an oxy/acetylene torch which comes in handy when I need to really go nuclear... I get him to apply the heat, and I work the solder and swear periodically.
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Re: Howto solder (beginners guide)

Post by BigSwede »

badbird wrote:
Edit: Apparently HCl is not recommended for stainless. I would never try soldering stainless anyhow with a home made flux. A real flux for stainless will have phosphoric acid and particularly fluorides. The latter are what really make it work well.
BigSweed, I have always found HCL to be quite effective flux for soldering brass / copper to stainless using Sn/Cu solder. As per previous posts just clean well, tin and don't over heat.
Are you saying there are corrosion or other issues using HCL with stainless or just that the fluoride fluxes are more effective?
I'm just parroting stuff I've read; I've never tried HCl on stainless, and if you've had success, then that's all I need to hear.

There's a mental bugaboo out there about soldering stainless,,, lot of people are scared of it. If a commercial flux helps a little above and beyond a basic acid flux, then I'd be all for it. What's a few cents worth of flux when working on an expensive piece?

But I agree with you in that after a couple of stainless solderings under the belt, it becomes "what's the big deal?" It's really not hard.

All in the surface prep!Edit: Something to add... when soldering stainless with water based fluxes, what happens is that the water boils away, then the salts melt. There should be enough flux applied so that when it's at heat, you can see a strong liquid pool of molten salts. If not there, add more flux!
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Re: Howto solder (beginners guide)

Post by badbird »

If a commercial flux helps a little above and beyond a basic acid flux, then I'd be all for it. What's a few cents worth of flux when working on an expensive piece?
Cant argue with that, if you can get the specialty fluxes at a reasonable price. Unfortunately some of these things tend to cost 2 or 3 or more times as much to obtain outside the US so compromises have to be made :ewink:
The hardest part I found soldering stainless was learning not to over heat thin wall material like kegs, unlike copper where the heat flows away quickly, with stainless once it reaches the solder working temperature it takes very little extra heat to keep it there so only a light touch with the torch is needed.
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Re: Howto solder (beginners guide)

Post by BigSwede »

badbird wrote:
If a commercial flux helps a little above and beyond a basic acid flux, then I'd be all for it. What's a few cents worth of flux when working on an expensive piece?
Cant argue with that, if you can get the specialty fluxes at a reasonable price. Unfortunately some of these things tend to cost 2 or 3 or more times as much to obtain outside the US so compromises have to be made :ewink:
The hardest part I found soldering stainless was learning not to over heat thin wall material like kegs, unlike copper where the heat flows away quickly, with stainless once it reaches the solder working temperature it takes very little extra heat to keep it there so only a light touch with the torch is needed.
VERY true. Copper wicks heat away at an insane rate, and unless the mass of copper is small, this means you need to keep applying heat. With stainless, it conducts heat poorly, so the heat applied to a spot tends to stay there.

Example: With a big sheet of copper, you apply a propane torch to the middle; the chances of getting it red hot at that spot are small unless the copper is thin. With stainless, you can create a local hot spot very easily.

Good thing it works this way. If kegs were copper, soldering fittings into them would be almost impossible. The entire keg would soak up all the BTU's applied.
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Re: Howto solder (beginners guide)

Post by Swedish Pride »

I'm planning to use Silver bearing solder paste and a butane torch to attach my cooper pipe to a stainless lid.
Any input on suitability from you pros?
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Re: Howto solder (beginners guide)

Post by rad14701 »

Swedish Pride wrote:I'm planning to use Silver bearing solder paste and a butane torch to attach my cooper pipe to a stainless lid.
Any input on suitability from you pros?
It may or may not work well for you... I'd suggest acid cleaning the SS before attempting... I use hydrochloric/muriatic acid...
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Re: Howto solder (beginners guide)

Post by BigSwede »

Swedish Pride wrote:I'm planning to use Silver bearing solder paste and a butane torch to attach my cooper pipe to a stainless lid.
Any input on suitability from you pros?
Ditto to Rad's suggestion. Make the SS look nasty. What I mean by this is, take some harsh abrasives to it, even a file, get through the pretty skin that it has leaving the factory. Ideally try some 220 or 320 silicon carbide paper, the black wet/dry stuff. Wet sand it, make it satin rather than shiny. Then, flux the hell out of it, preferably with a flux designed for SS (it'll have fluoride salts, great stuff for SS); failing that, try a strong acid flux. I know your paste solder carries its own flux, but I'm a bit leery not knowing more about it.

Best would be to tin the SS separate from the copper. This prevents the Cu from "stealing" all the heat. Get the solder to bite on the SS. Once you've got it tinned, flick/wipe the excess with a cotton cloth while it's still molten so that all that is left on the SS is a solder "skin".

If you can get that, then joining to the copper is almost guaranteed.

DON'T overheat the SS lid! Very easy to do. SS conducts heat poorly, and you can overheat locally in seconds. If it turns black or purple, too much heat. Go slow, get the tin on, then join the parts. Good luck!
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Re: How to solder (beginners guide)

Post by Swedish Pride »

Thanks Rad, Big Swede.
Sounds like it's more to it than I thought :/

I might just chicken out and screw the pipe on to the lid with ss bolts and nuts, I've seen it done in this forum but was worried about the connection might not be strong enough.

What would happen if you overheat the SS, bar from going black and purple does it lose it's "safe for stilling spirits" stamp of approval or just not easy on the eye ?
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Re: How to solder (beginners guide)

Post by BigSwede »

Swedish Pride wrote:Thanks Rad, Big Swede.
Sounds like it's more to it than I thought :/

I might just chicken out and screw the pipe on to the lid with ss bolts and nuts, I've seen it done in this forum but was worried about the connection might not be strong enough.

What would happen if you overheat the SS, bar from going black and purple does it lose it's "safe for stilling spirits" stamp of approval or just not easy on the eye ?
The metallurgy won't really change, the bad thing is that those colors are oxides of iron and other alloying elements in the steel. Oxides that form a skin and prevent the solder from biting. You'd have to let it cool and start all over. A good flux will remove them while soldering, but only up to a point. I think most people use too LITTLE flux.

Is there any way you can experiment with a similar SS lid/whatever it is? It's really not all that hard, I know we make it sound like it is.

Some guys have success using an iron rather than a torch. With a iron (needs to be BIG, say 200+ watts, an electronics iron won't work) - you rub the iron with flux applied onto the SS, then add solder, rub more. The rub action breaks the oxide layer and gets the solder onto the SS.

Go for it, you can't hurt anything, you can always take it apart and clean it up to try again. If you want to use the paste, I'd also have on hand separate flux, preferably one for SS.

Or... idea... if you can find one of those big irons like I mentioned, I'll bet it'd go well with the paste solder in the "rub" methodology.
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Re: How to solder (beginners guide)

Post by Swedish Pride »

Thanks Big Swede.

I think I'll just get a tin solder and flux and chance my arm if there is no damage to the SS if I mess up :)
Once I get all the parts for my build I'm sure I'll be here crying and looking for advice again :lol:
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Re: How to solder (beginners guide)

Post by frodo »

http://screencast.com/t/4r2phGTZFRym" onclick="window.open(this.href);return false;" rel="nofollow

http://screencast.com/t/JGlZs3mTcA" onclick="window.open(this.href);return false;" rel="nofollow
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Re: How to solder (beginners guide)

Post by Andyj »

really handy tips.
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Re: How to solder (beginners guide)

Post by brewstillski »

Finalizing plans to add a thumper to my setup and this thread may just have convinced me to finally give soldering a go. Definately gonna practice on some scrap pipe until confortable enough for the real thing. Thanks.
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