Soldering / Brazing copper to stainless steel keg

[bellybuster]

soldering SS to SS or copper to SS is less about the solder and most about the flux. As mentioned a dozen times above, Harris Stay Clean.

hard to find in Canada, Ebay always has it.

I've also found the standard propane torch to be more than adequate

[Swedish Pride]

I've actually just manage to solder a copper connetion to my SS bowl using just plain old plumbers flux and lead free solder.
Don't know how i managed, beginners luck for sure. and yes it's ugly but does the job.


Wouldn't been able to without all the help on this site for sure

[chris_zx2]

I've actually just manage to solder a copper connetion to my SS bowl using just plain old plumbers flux and lead free solder.
Don't know how i managed, beginners luck for sure. and yes it's ugly but does the job.


Wouldn't been able to without all the help on this site for sure

Can you explain the steps you took to manage this?

[cranky]

Here's how I did mine.
https://www.youtube.com/watch?v=BBZPocv ... fA&index=1" onclick="window.open(this.href);return false;" rel="nofollow
That link came from this thread
http://ww.homedistiller.org/forum/viewtopic.php?t=36347" onclick="window.open(this.href);return false;" rel="nofollow
Mine came out the same way as SP's

[chris_zx2]

Here's how I did mine.
https://www.youtube.com/watch?v=BBZPocv ... fA&index=1" onclick="window.open(this.href);return false;" rel="nofollow
That link came from this thread
http://ww.homedistiller.org/forum/viewtopic.php?t=36347" onclick="window.open(this.href);return false;" rel="nofollow
Mine came out the same way as SP's

Yeah I read / watched yours but you used the proper flux, SP says he managed with regular flux!?

[cranky]

Here's how I did mine.
https://www.youtube.com/watch?v=BBZPocv ... fA&index=1" onclick="window.open(this.href);return false;" rel="nofollow
That link came from this thread
http://ww.homedistiller.org/forum/viewtopic.php?t=36347
Mine came out the same way as SP's

Yeah I read / watched yours but you used the proper flux, SP says he managed with regular flux!?

Sorry, wasn't mine was Bellybusters but I did the exact same thing with the right flux. I have read that some have had success with regular plumbing flux but you really should buy the right flux. I got mine on Amazon and it didn't take long to get it but trying to do this with the wrong flux or solder is just asking for failure and frustration.

[chris_zx2]

Here's how I did mine.
https://www.youtube.com/watch?v=BBZPocv ... fA&index=1" onclick="window.open(this.href);return false;" rel="nofollow
That link came from this thread
http://ww.homedistiller.org/forum/viewtopic.php?t=36347" onclick="window.open(this.href);return false;" rel="nofollow
Mine came out the same way as SP's

Yeah I read / watched yours but you used the proper flux, SP says he managed with regular flux!?

Sorry, wasn't mine was Bellybusters but I did the exact same thing with the right flux. I have read that some have had success with regular plumbing flux but you really should buy the right flux. I got mine on Amazon and it didn't take long to get it but trying to do this with the wrong flux or solder is just asking for failure and frustration.

That's what I plan on doing. Thanks guys!

[corene1]

Well I am not an expert. But silver solder melts at, what, 400-500F? And your brazing flux here is not "chemically active" below 800F. Might be a problem. Just sayin is right, try Harris stay clean flux. And solid core silver solder, like Harris stay brite8. I've also used Oatey brand solder.

I have to agree with you here. Stay Silv is designed for a high silver content and higher temp brazing of stainless . 45% silverbraze flows at 1125 degrees. Stay Brite 8 flows right at 525 and the liquid stay clean is best for it as with other low silver bearing solders and lead free solders. I am interested to see a picture of the copper to stainless joint that was done with the Stay Silv and Oatey solder as I have never used that combination. Always something to learn.

[Swedish Pride]

I've actually just manage to solder a copper connetion to my SS bowl using just plain old plumbers flux and lead free solder.
Don't know how i managed, beginners luck for sure. and yes it's ugly but does the job.


Wouldn't been able to without all the help on this site for sure

Can you explain the steps you took to manage this?

So first i tried to wet the SS but instead it turned in to a burnt mess with a few blobs of solder
This was followed by cursing and giving up, so I came back to it the next day.

So I started by cutting the blobs of solder of the bowl as they were far to raised for me to line the copper up properly.

Then I went at the SS with some sandpaper I had laying about, i wasn't able to get all of the burnt bits off but prob 98% of it was gone.
I sanded the copper as well on the bottom and a bit up the side, then i wiped both SS and copper with some 30% low wine I had, foolishly I've always thrown the fores away so the low wine was the only alcohol i had about.

Then I thew on a good bit of flux on the SS, bottom of the copper and inside the copper, I also screwed the copper in to the lid with two SS screws and nuts just to ensure the copper and SS had a good contact area.

Instead of feeding solder to the copper as it heated up I wrapped a ring of solder around the copper with a bit overlap. I also added a ring of solder inside the copper.

Turned the propane on as low as I could get it, started to heat the SS bowl as far away from the copper as I could get it just to get the SS up to heat, i think a total less than 10 sec, didn't want to overheat the SS.
Then I moved on to heating the copper at the very top again not to overheat the SS.
I kept moving the flame about but always as far a way from the SS as possible, once the flame bouncing of the copper turned green I flicked the flame down towards where the copper and SS meet, literally a flick , less than half a sec, and then back to the top of the copper.
The Solder started to flow, kept the heat on for a few more sec's, still only at the top of the copper and then turned the propane off.

I stood back and scratched my head in bemusement as I inspected the joint as I cant get normal copper to copper to work that easily, like I said a total fluke, but all methods applied came form reading here on this forum.

I'm not saying that this is a good or the proper way of doing it, it just worked for me, I was just trying it as for the hell of it as my everlasting gasket failed on the last run so i needed to repair it, no way in hell I would have expected it to pay off.

I should have bought a lotto ticket as well

[chris_zx2]

SP just to be thorough, you say you used regular plumbing flux, could either post a pic of the flux or tell me the brand? I'm just curious how this is even possible, when everyone says it isn't? Did you figure out the one and only way to do it? I'm sure the inside and outside ring of solder helps because they flow together but how strong is the connection to the SS; if you flex the bowl will it separate?

Also you said you screwed in the copper, do you mean you have a threaded adapter on both sides of the bowl pinching the bowl? If that's the case then the copper adapters are doing all the work and the solder is, for now, just filling any gaps.

[Kegg_jam]

I've had success using regular flux. It is possible with careful cleaning and heating practice.

[Swedish Pride]

I've seen other do it with regular flux as well, I know Rad have for sure, think other have done it as well.

This is the flux i used, just regular water based flux for your copper pipes
http://www.diy.com/departments/gosystem ... 293_BQ.prd" onclick="window.open(this.href);return false;" rel="nofollow
And the solder
http://www.diy.com/departments/gosystem ... 620_BQ.prd" onclick="window.open(this.href);return false;" rel="nofollow

As for attaching hte copper i did somethign like a inverted easy flange, so the lip is on the inside of the pipe, driller holes through the copper and through the ss.
Looked similar to this before I covered in solder
http://homedistiller.org/forum/viewtopi ... 2&start=30

Sure the screws hold it to some extent but I pulled at the copper a fair bit to test it and it seems fairly sturdy, I didn't whack at it with a hammer or anything to try it's strength but it seems sturdy enough.
As I said, not preaching for anyone to do this, silver solder will be stronger and the right tool will probably make it easier to do, just saying it worked for me

But there is no harm trying it if you already have normal solder and flux, worst thing that can happen is that you waste a bit of time and material.

[chris_zx2]

Awesome, I just was under the impression it was "chemically" impossible! Time to go practice!

[rad14701]

I use that exact same flux, and also use Hydrochloric/Muriatic acid at times, for soldering SS to copper or SS...

[corene1]

I have been keeping track of this post and am seeing a variety of techniques for joining copper to stainless. I saw where the OP said he had good luck with the Harris stay silv silver solder paste. Today at work I tried a bunch of different combinations and in my thoughts the stay silv does not become active enough to clean the base metals at the temp that the solders flow. Standard lead free flows at about 450 and stay brite 8 flows at about 525. That paste is not active till 800 all the way up to 1600 . It says right on the label for brazing with safety silv brazing filler or other similar brazing fillers, not solder. Needless to say I could not get a quality joint with any of the combinations. I went back and did one with Harris stay brite 8 and harris stay clean liquid flux and got excellent results. So to the OP please give your soldered joints a good test to make sure they are solid and well bonded. I don't want to say it can't be done but I had quite a problem with the stay silv flux with standard solder ,It works great for silver brazing though. Here is a picture of the quality bond that the stay brite 8 and stay clean flux gives . Nice wetting action and complete bond inside and out.

[slowswim]

Thanks for the tinkering, corene1.

I'd like to follow up my previous post with an unfortunate find. After several unsuccessful attempts (see previous posts), I used the Harris Stay Silv flux and Oatey solid core solder. I soldered the copper pipe and stainless ferrule into what I thought was a good joint; it was solid and didn't move. I put the piece in vinegar/water solution over the weekend to clean it and can say the joint completely fell apart when I took it out yesterday.

I've since ordered the Harris Stay Clean flux from Amazon and expect it by Friday. I'll relay my efforts once I've had yet another chance to solder these pieces.

[slowswim]

the Harris Stay Clean arrived in the mail today. It took about 2 minutes to solder the copper and stainless ferrule. Worked like a champ.

[cranky]

the Harris Stay Clean arrived in the mail today. It took about 2 minutes to solder the copper and stainless ferrule. Worked like a champ.

Guess that only proves what I (and many others) said,

you really should buy the right flux... trying to do this with the wrong flux or solder is just asking for failure and frustration.

In the long run it saves time money and effort.

[Anthoney]

Just FYI.

The silver solder/brazing flux powder you make into a paste with water is basically borax and is, as commented, for high temps.

The lead free solder is mostly tin with a bit of copper and the excellent Harris flux is zinc chloride or what used to be called killed spirits. It is, again as mentioned, active at lower temps. If, like me, Harris is unavailable in your part of the world search for zinc chloride flux. Or do as I did, if you have the skills to do it safely.

Copy the old boys who used to make their own back in the day when that was standard practice. Dissolve zinc metal in concentrated hydrochloric acid a bit at a time until it stops bubbling and dissolving. This is killed spirits. Although not as concentrated as before you dissolved the zinc this is still pretty acidic so be careful with it. I use a small artist's brush to apply it.

[frodo]

I have been keeping track of this post and am seeing a variety of techniques for joining copper to stainless. I saw where the OP said he had good luck with the Harris stay silv silver solder paste. Today at work I tried a bunch of different combinations and in my thoughts the stay silv does not become active enough to clean the base metals at the temp that the solders flow. Standard lead free flows at about 450 and stay brite 8 flows at about 525. That paste is not active till 800 all the way up to 1600 . It says right on the label for brazing with safety silv brazing filler or other similar brazing fillers, not solder. Needless to say I could not get a quality joint with any of the combinations. I went back and did one with Harris stay brite 8 and harris stay clean liquid flux and got excellent results. So to the OP please give your soldered joints a good test to make sure they are solid and well bonded. I don't want to say it can't be done but I had quite a problem with the stay silv flux with standard solder ,It works great for silver brazing though. Here is a picture of the quality bond that the stay brite 8 and stay clean flux gives . Nice wetting action and complete bond inside and out.

P4200021.JPG

P4200022.JPG

NICE BEAD!! ...

[frodo]

I have not used this stuff,,but it looks easy as hell

[cranky]

I think I have something like that in my toolbox and for some unknown reason have been reluctant to use it. I thought about it last week when I ran out of solder again and just needed a little bit to finish the job but just waited until I could get to the hardware store. I might have to give that a try sometime.