Soldering Stainless steel

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For that application I would strongly recommend using this flux with the Harris Stay-Brite-8 solder:
Stay-Clean Aluminum Flux
It works very well for soldering Stainless Steel AND Aluminum.

Do a Google on "Harris Stay-Clean Aluminum" to get a listing of a lot of places to get it.
 
I've gotta say, this thread is awesome :ban: ... much thanks to BargainFittings and everyone else who contributed to this thread.

I recently soldered a washer on my sight glass fitting (bargainfittings weldless sight gauge) so I could use an external silicone gasket. Used Harris Stay-Brite Solder and Stay-Clean Flux. After a little practice, I was able to make a clean bond ... this stuff is great.

Here's the finished product ...

IMAG0131.jpg

Testing the seal in my kettle (this was installed the hole for my bulkhead/ball valve ... I'll be positioning the sight glass as low as possible on the kettle) ...

IMAG0133.jpg
 
Finally!!! :rockin:
It's not pretty at all, but I finally got a good solder all the way around. I soldered a washer to a street elbow for a bulkhead fitting. My 5 keys to success: 1. Oatey liquid soldering flux (clear liquid), when it boils off, it pulls the contaminants off of the pieces in salt-like flakes. 2. Don't heat the joint directly. It seems carbon deposits form where the flame is applied and that is no help in soldering. 3. Use gravity. The flattest piece in your work should be horizontal to help keep all your solder from running away. 4. A tight joint. Prevents solder from running through. 5. work just above the melting temp. be able to move your work off the flame easily.
 
I pulled a dimple in two 1/2" holes today and both of them cracked on the bottom. It looked like it was pulling the bottom more than the top. I was able to solder them anyway. I soldered a 1" half coupling to the outside without pulling a dimple. It looks strong as others have made similar comments. I am not sure that I am going to pull dimples for my other keg.
 
I pulled a dimple in two 1/2" holes today and both of them cracked on the bottom. It looked like it was pulling the bottom more than the top. I was able to solder them anyway. I soldered a 1" half coupling to the outside without pulling a dimple. It looks strong as others have made similar comments. I am not sure that I am going to pull dimples for my other keg.

What size hole did you drill for those dimples that cracked? Which reducer did you use for the tool? I just got everything together to start this project, but this concerns me. I really don't want to mess up my new stainless pot.
 
I punched a 1 1/4" hole and used the reducer from McMaster Carr that was listed on this site. I even used graphite lube to try to prevent the cracking. For some reason it was not pulling straight, and that was the cause of the crack. The soldering was able to fill the crack enough that it is not a big issue. Just cosmetic. Probably need to solder all of the couplings and washers together to give it the best shot of puling straight through. I saw a post where this was done.
 
yeah you need to be sure that both ends are centered and that the whole thing is square against the side of the vessel. otherwise you get wandering. soldering the washers to both ends of the reducer definitely helps this.
 
Quick question. I've got this silver soldering thing down, but am wondering if it'd be a good or bad idea to solder in a half coupling in the side of a pinlock keg.

I use them for pressure fermenting. I'd like to add thermowells to them.

Under normal circumstances, it would never go over 30psi in the keg.

I'm just not sure if the silver soldering can hold the pressure.
 
Quick question. I've got this silver soldering thing down, but am wondering if it'd be a good or bad idea to solder in a half coupling in the side of a pinlock keg.

I use them for pressure fermenting. I'd like to add thermowells to them.

Under normal circumstances, it would never go over 30psi in the keg.

I'm just not sure if the silver soldering can hold the pressure.

My pressure tank (on my home water system) cuts on @ 30PSI and off at 45PSI with soldered copper pipe in there, if you are only going up to 30PSI then I imagine it would hold just fine. If you Spundig valve gets stuck though, you may be in for a pressurized shower, or a fermentation chamber full of beer. :drunk:
 
wyzazz said:
My pressure tank (on my home water system) cuts on @ 30PSI and off at 45PSI with soldered copper pipe in there, if you are only going up to 30PSI then I imagine it would hold just fine. If you Spundig valve gets stuck though, you may be in for a pressurized shower, or a fermentation chamber full of beer. :drunk:

Heh. That's why I said normal circumstances. Normally, my ferments aren't even near 30psi.

Thanks for the input! Now I just need to grow the balls to cut into my perfectly good pinlocks.
 
Not sure how well that would work with a thermowell as deep as the keg.... you know, getting the lid out.
 
Not sure how well that would work with a thermowell as deep as the keg.... you know, getting the lid out.

It sounds like you should consult the cure for a short hose thread.

It looks like if you offset the thermowell on the lid you could go pretty deep. I bet 10-12 inches is very doable. Maybe more.
 
I saw somewhere in this encyclopedia of a thread that someone preferred to butt solder the 1" coupling for a heating element. What about the curve of the vessel? Two of the sides of the coupling won't be making very good contact with the vessel. Is this and issue? While the whole pull through "tool" technique looks rock solid, I really really fear cracking a brand new SS pot.
 
Well, I used the Harris Stay-Brite 8 solder, which I believe is supposed to be better for filling gaps. However, with the 1" nut, there's not a whole lot of a gap anyway - my first one was done with regular Harris Stay-Brite, and it's been in service for over a year now.

Long story short, at least with my vessels the curve isn't an issue.

-Joe
 
Well, I used the Harris Stay-Brite 8 solder, which I believe is supposed to be better for filling gaps. However, with the 1" nut, there's not a whole lot of a gap anyway - my first one was done with regular Harris Stay-Brite, and it's been in service for over a year now.

Long story short, at least with my vessels the curve isn't an issue.

-Joe

Roger that. Thanks. The Stay-Brite 8 is what I was planning to use. I'm going to do this on a thinner 9 gallon kettle so I was thinking about using something kinda similar to the "tool" to squeeze a flat spot where the nut or coupling would lay. Sounds like I might not need to, though a lot of these mods seem to be happening on converted kegs which have a couple more inches of diameter. I'll have to check it out when my kettle arrives in a couple days.
 
I am looking for ideas to solve a small problem. The first solder I did the joint was fairly tight and the solder stayed at the joint. The second joint wasn't so tight so solder flowed through onto the threads of the fitting. Has anybody found a material to back and plug up the backside? Just temporarily / removeable. Would plumbers putty work or would that burn? Thanks.
 
You'll likely need to pick up a plug, getting one in Brass will probably be cheaper than SS.
 
Are you using Stay Brite #8? The more silver content, the bigger gaps it will bridge. If you still have trouble, You can fill in some of that space by wrapping some stainless wire so it lays in the threads on the nipple.
 
Anyone have their coupling fail with direct heat???? Thinking of having my bottom couplers tig welded in my kegs and soldering the rest. Comments??

Awesome thread!!
 
Anyone have their coupling fail with direct heat???? Thinking of having my bottom couplers tig welded in my kegs and soldering the rest. Comments??

Awesome thread!!
That cannot happen (solder failure) as long as there is fluid (water) above the level of the soldered connection.
 
^^What he said^^ Have you ever tried to solder a waterline with just a few drops of water left in it? I suppose if you were too worried you could snag some of Bobby M's Heat Shields when he gets them finished up, that would certainly reduce the amount of heat on the couplings.
 
I wonder about that, though. Is the heat transfer from the outside of the keg (where the fire is) to the inside (where the water is) fast and efficient enough to prevent this from ever being an issue? I'm just thinking of when I cool off my wort; sometimes I'll run the waste water from the chiller over the bottom part of the keggle, and that mo'fo will steam and sizzle like nobody's business - a lot more than I would expect if the outside of the keg was only 212°. It'll keep steaming for ten or fifteen seconds; if the keg's exterior was only a little over 212°, you wouldn't expect it to steam up so aggressively and for so long.

If the temperature of the keg's exterior was being fully kept in check by the liquid inside, I wouldn't expect that huge "WHOOSH" of steam when I run the waste water over it.

With that said, I've never heard of a soldered joint FAILING. I'm just not convinced that the heat transfer within the keggle is efficient enough to keep the whole keg at essentially the wort's boiling point.
 
Stay-Brite solder has a melting point of 430F (MSDS) so you can extrapolate from there. Does the outside of your kettle get to 400 degrees under normal operation? I suppose anything is possible but I seriously doubt it gets that hot unless you have concentrated flame directly on the fitting.

I'd imagine that my polycarbonate sight glass would melt before a soldered fitting would become liquid again, the polycarbonate I use has an operating temp max of 250F.
 
I think the very bottom roll of a converted keg boil kettle will get to around 400-500F because it takes some time for the heat to travel up the 4" or so to get to the liquid inside. The bulkheads are a lot closer to the liquid and might see 240-250F. No way you're desoldering those things without a ton of misuse like a full flame run-dry.
 
Anyone have their coupling fail with direct heat???? Thinking of having my bottom couplers tig welded in my kegs and soldering the rest. Comments??

Awesome thread!!

I've had my silver solder joints fail from mechanical torsion more than heat. The BK with it's valve and T sticking out failed first since it was getting torqued while cleaning as well as the MT valve for the same reason. MY HLT seemed to survive the best. I was tired of cleaning and reflowing the cracked silver solder joints and finally just cleaned them all up and had them TIGd. Just my experience YMMV.
 
bajabrewer7 said:
Why do we have to make the dimple? Couldn't I just solder a coupling on a tight hole?

Yes you can, but it's nowhere near as strong. The dimple increases the contact area of the solder on the fitting.
 
pickles said:
Yes you can, but it's nowhere near as strong. The dimple increases the contact area of the solder on the fitting.

The pull through method also gives it a little mechanical strength. I do mine bassackwards and make a well on the outside of the keg. The coupling sits on the outside but the well allows for a nice fillet of solder without it running all over. I have done about two dozen like this without a failure yet.

ForumRunner_20111208_182527.jpg
 
You will need two kits. Those kits last for about 4 fittings each in my experience. You do not need to be shy with the flux though. Go crazy with that stuff before, during, after and cleanup. Then go over everything with bar keepers friends and a paper towel to remove flux and shine it all up.
 
The pull through method also gives it a little mechanical strength. I do mine bassackwards and make a well on the outside of the keg. The coupling sits on the outside but the well allows for a nice fillet of solder without it running all over. I have done about two dozen like this without a failure yet.

View attachment 40119

Very nice. I am getting ready to build another E Keggle. I want to use this Pull thru method. Pulling into the keg. I Haven't decided if I will TIG or do the solder. My current one is Tigged but the inner seam is not very nice or clean. The weld on the outside looks great tho.
That is why I was thinking about using this pull method to give a nice clean seam on the inside.
Do you have any pictures of the inside of the keg? What method or tool size did you use to make your dimple?
Thanks.
 
I used the little Harris bottle and soldier kit. I've done 7 new joints and had to fix two joints I busted loose messing with the valves. I have at least one more joint left out of my kit.

Get the kit, or lifetime supply of liquid flux and silver soldier.

-=Jason=-
Sent from my HTC using Home Brew Talk
 
Wondering if you guys can give me some advice on the best way to do this.

So I was quite dumb when ordering my false bottom from Jaybird and totally forgot about the lip at the top of my kettle, so I didn't get a hinge put in it. As you can see the FB just barely can't fit in.

So I was thinking I'd cut a slit in the lip so I can slide it through. But if you look on my pot, cutting that slit would leave me with an exterior hole as well. Would I be able to solder that shut? I don't really have much experience with soldering, so I'm not sure how I'd get the solder to stay in slit and make a seal. Is there something I could put on the backside the solder wouldn't adhere to, then remove it once it's solidified? I have a friend whom has a MIG welder, but buying one of these kits would be cheaper than purchasing some stainless core wire and I think his welds are probably a bit ugly, too :p

https://www.t-mobilepictures.com/myalbum/photos/photo24/35/da/d738b764ae8a__1323130830000.jpg
https://www.t-mobilepictures.com/myalbum/photos/photo17/d5/66/58dd07ee6f53__1323130744000.jpg
https://www.t-mobilepictures.com/myalbum/photos/photo09/e1/14/5f25469cdd34__1322271488000.jpg
 
Hammer the ridge flat in two spots opposite each other so the false bottom will slide past?

Edit: Put a backer behind the metal so you don't deform the hell out of your kettle.

Maybe need to use a flat bar or something to extend out to allow you to hammer it flat.
 
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