Soldering SS Ferule to Copper Troubles

[FishNChips]

I've gotten my whole build worked out except for the SS ferules. Using Harris Stay Clean liquid flux and Solder (tried silver and regular plumbing) I can't get the solder to stick! There is only one more thing I have left to try and that's use another clean ferrule as I have grinned this one down five times.

My process is, sand like crazy, isoropyl alcohol, generous liquid flux with a q-tip and clean at the same time, heat evenly with propane (also tried acetylene) and tap solder until it melts. RIght now, I'm just trying to tin the stainless to see if I can get something to stick.

Note: This process is done on a ferrule that I had already failed with two times.

What I notice is that after some heat, the flux will begin to evaporate and the stainless gets a black tinge on the outside, no matter where I apply heat. I reapply the flux, some burns, and some sticks. Heat again and before the solder melts, flux is gone and stainless is black.

What am I doing wrong? My last resort is to take it to a shop and have them do it for me.

Here a link to the photo after my last attempt at soldering: https://photos.app.goo.gl/gGihnQ56LJpsnzDx8

[Expat]

Sounds like you're burning the flux. Heat should be applied indirectly to the joint by working the largest of the pieces, and increased until the joint is at temp. The procedure I use, as learnt from an article somewhere on here is to fashion a ring of solder around the joint. When it's hot enough to run, the solder will go. Avoid directly heating the solder.

At this point you'll have to clean the hell of the surfaces to create a clean work area.

[FishNChips]

Sounds like you're burning the flux. Heat should be applied indirectly to the joint by working the largest of the pieces, and increased until the joint is at temp. The procedure I use, as learnt from an article somewhere on here is to fashion a ring of solder around the joint. When it's hot enough to run, the solder will go. Avoid directly heating the solder.

At this point you'll have to clean the hell of the surfaces to create a clean work area.

Thank you for the reply. Okay, should I be heating the stainless indirectly by putting it in the pipe and heating the copper? Right now I'm pulling it out and trying to tin outside of the pipe and applying heat to the inner side of the ferrule.

[FishNChips]

Just tried it again with a clean ferrule and failed again. Ferrule was coated with black before solder would melt and adhere. This time I had it pin the copper pipe. Is it really that finicky? Is the point at which the solder melts that close to that which the flux fails?

[StillerBoy]

Part of your issue with soldering the ferrrule is using the improper tools, cleaning and application..

All the part need to be properly sanded, cleaned, and the s.s. cleaned with acetone or lacquer thinner.. then prep with the properly paste, for s.s. Stay Clean liquid flux or Superior 71 paste (both are very good for s.s.) then the proper propane tip, a fire brick or regular one, solder which has some silver content to it, and time..

Using the proper propane tip, direct the flame at the base of the ferrulw where the s.s. ferrule makes contact with the brick, and about an inch above the end of the ferrule, alternating from bottom and top, heating it slowly up to the point where the solder rings inside start to soften or melt.. then slowly work it until the solder starts to appear on the outside of the ferrule.

The picture provide some visual insight..

Mars

[Swedish Pride]

heat the copper not the ss, apply more flux if it blackens and just keep heating the copper.
you got the right tools, just keep at it, you'll get it soon enough

[Pikey]

I've got an old stainless sink top - is there any benefit to be had in chopping that up and trying to solder bits back on or solder them together for practice ?

[Swedish Pride]

well for thin ss to thin ss I'd recomend a 150w soldering iron, it's the ducks nuts

[OtisT]

Just something to check. Make sure your flux is appropriate for the solder you use, specifically the correct temp. Likely not an issue for you but thought I would mention it just in case.

Common plumbing flux melts at a relatively low temp just before a typical soft solder melts. The low temp flux is not so good for high temp silver solder because the low temp flux melts off long before you reach solder temp and that can foul the joint.

Conversely, don’t use high temp flux with low temp solder, or you will melt the solder before flux. Also bad.

Otis

[Swedish Pride]

stay clean flux and regular lead free solder work good, get her done

[corene1]

You mentioned that you tried plumbers solder and silver solder. What type of silver solder. A true silver solder such as safety silv 45 flows at 1125 degrees and a high temp flux is required, the liquid flux will not handle that much heat. A silver bearing solder such as Harris stay brite 8 is only 6% silver and flows at 525 degrees and works well with the stay clean liquid flux. It also makes a very good joint when soldering stainless to copper. Just a thought.

[Pikey]

well for thin ss to thin ss I'd recomend a 150w soldering iron, it's the ducks nuts

Do Ducks HAVE "Nuts" ?

I'm not really thinking of it as "thin to thin" - just as "practice" .

All this advice about sldering stainless - is scary !

Eventually I'm looking to stick a "fill / cleaning" port onto a stainless keg.

I have "Bakers No3" (Killed Hydrocloric acid - same as the "Harris" ) - But Silver solder is a real problem to track down in UK.

I have a BIG propane torch sitting on a variable pressure regulator - which we used to use for laying flat (felt) roofs and boiling the kettle for "Tea" - I have a nice little propane torch for finer work. Either of these will do "copper to copper" easily. and I have purchased an old style soldering iron (Big lump of copper on a handle - which I was taught to solder with - You heat it up in a fire or on the cooker, then "tin it" and use the heat to melt and spread the solder.

Just at the moment - what I'm wanting to do is what seems to be the difficult bit - ie get the solder to "Tin" the stainless. To my simple mind - if I can get it to do that - then sticking two "Tinned bits together" - should not be hard !

I was taught as a kid that if you're using Bakers, you din not need to be anywhere near as "clean" as "that silly paste stuff" because the flux was in itself a cleaner.

I guess I just need to stop procratinating and give it a go !

[StillerBoy]

All this advice about sldering stainless - is scary !

No different than soldering copper to copper..

Mars

[Twisted Brick]

heat the copper not the ss, apply more flux if it blackens and just keep heating the copper.
you got the right tools, just keep at it, you'll get it soon enough

As a superior conductor, the copper will transfer enough heat for the solder to flow before the entire ferrule heats up. The trick is to be patient enough to heat 360* of pipe before applying the solder.

[Swedish Pride]

Just get lead free solder pikey, its cheaper and easier to work with.
Its plenty strong for your need.

[hellbilly007]

This kit has been used by many for soldering stainless to copper and stainless to stainless. This is same solder you mentioned using, perhaps you have a solder that doesn't match the heat.

Also, I've never used isopropyl alcohol for cleaning a solder joint, only acetone. I've seen isopropyl leave a white, chalky residue when used on other projects.

[corene1]

Just thought I would post this link to Harris products. It is quite informative as you can click around and see what type solders and brazing fillers work best with certain base metals. I have relied on it for many years at the shop and it has always been very reliable. Just pick solder or brazing then select material to be joined and it will give you the proper combination for a nice clean and reliable joint. The technical data will give the flow temps as well as the solders make up and gap filling ability. It is a very good reference link for basic soldering. Some people may be able to make good joints using a different combination but I believe in making things as easy as possible for any project and have found through time that a silver bearing solder makes it easier to make a clean reliable joint on any copper to stainless or stainless to stainless joint. Just my thoughts though.
http://www.harrisproductsgroup.com/en/Products.aspx

[FishNChips]

Thank you to everyone for the help. Sorry, I said isopropyl in the post, I meant to say acetone. My problem was, I was burning the flux before I melted the solder. Trying to tin the SS before hand was a mistake. By putting it in the copper, it shielded the flux from direct heat.

I used a propane torch, Harris stay clean liquid flux, and regular plumbing solder.

My final process was:

Sand down copper and stainless really well (until it looks as brushed as it can get).
Clean with acetone, both pieces. (May not have been necissary)
Apply Liquid flux, over entire surface in contact.
Connect pieces and begin heating.
Here's the tricky-ish part: Heat from inside and outside of joint. Heating outside will get the solder to melt and inside will help it flow through the joint. If you see green flame, you are applying too much heat or too direct of heat.
Continue using only enough heat to melt the solder all around the joint.
Quench the part and you're good to go.

Overall, it took me about 10 tries and many of those I had to de-solder and use a belt sander to grind down to fresh material. Again, thank you all.

[Twisted Brick]

I read here somewhere that quenching a hot soldered joint can weaken it, so always just let my parts cool slowly on their own.

[Boozewaves]

Overall, it took me about 10 tries and many of those I had to de-solder and use a belt sander to grind down to fresh material

I also had trouble connecting stainless to copper . glad you managed to do it in the end . I tried using propane through a torch with silver solder , I could not get the parts hot enough , using an arc welder got it hot enough to melt but the results were not very good , at least I did not think it was a good join , when I grinded the chunks of melted rod off the piece it turned out it was actually a pretty good join , however I have asked somebody to tig weld the pieces for me now , 2 parts are done , just waiting for the other piece , I gave him the silver solder rods as I have no use for them , will have to pay them for their time as well but thats o.k . I think if I had known how hard it would be I would have used pre made stainless steel tubes with ferrules already attached and copper scrubbies in the column

[Pikey]

Overall, it took me about 10 tries and many of those I had to de-solder and use a belt sander to grind down to fresh material

I also had trouble connecting stainless to copper . glad you managed to do it in the end . I tried using propane through a torch with silver solder , I could not get the parts hot enough , using an arc welder got it hot enough to melt but the results were not very good , at least I did not think it was a good join , when I grinded the chunks of melted rod off the piece it turned out it was actually a pretty good join , however I have asked somebody to tig weld the pieces for me now , 2 parts are done , just waiting for the other piece , I gave him the silver solder rods as I have no use for them , will have to pay them for their time as well but thats o.k . I think if I had known how hard it would be I would have used pre made stainless steel tubes with ferrules already attached and copper scrubbies in the column

Did you just put the SS in the arc BW and go to it ? or did you use the flux ? I got some stainless rods to give Sttinless to stainless a go - ot tried it yet.

You're in Uk ? where did you get the solder if you don't mind me asking - I struggled to find it except silly little bits for "Jewellery "

[Boozewaves]

Did you just put the SS in the arc BW and go to it ? or did you use the flux ? I got some stainless rods to give Sttinless to stainless a go - ot tried it yet.

You're in Uk ? where did you get the solder if you don't mind me asking - I struggled to find it except silly little bits for "Jewellery "

Hi Pikey , yes tried to use it similar to using a brazing rod with the welder , did not use flux , it was an experiment really , it seems to work and was a firm joint , looked really good after I grinded it down with a sandpaper flap disc , I was just getting it ready to go to be tig welded by somebody else , pretty sure I could have continued to use the silver solder to do the join

at that moment in time though the person with the tig welder had been phoned and asked and said they would give it a go , I thought tig weld would be better and the pieces I have had back are really well done and waterproof , its gonna cost me around £40 but for part of a 3 inch ccvm column that will be quite heavy because of the stainless tee , it will need to be a strong join so worth paying him ,

silver solder was from here , I got 2 packs for £24 https://www.ebay.co.uk/itm/SILVER-BRAZI ... 3307037893

[StarkBlood1980]

Did you just put the SS in the arc BW and go to it ? or did you use the flux ? I got some stainless rods to give Sttinless to stainless a go - ot tried it yet.

You're in Uk ? where did you get the solder if you don't mind me asking - I struggled to find it except silly little bits for "Jewellery "

Hi Pikey , yes tried to use it similar to using a brazing rod with the welder , did not use flux , it was an experiment really , it seems to work and was a firm joint , looked really good after I grinded it down with a sandpaper flap disc , I was just getting it ready to go to be tig welded by somebody else , pretty sure I could have continued to use the silver solder to do the join

at that moment in time though the person with the tig welder had been phoned and asked and said they would give it a go , I thought tig weld would be better and the pieces I have had back are really well done and waterproof , its gonna cost me around £40 but for part of a 3 inch ccvm column that will be quite heavy because of the stainless tee , it will need to be a strong join so worth paying him ,

silver solder was from here , I got 2 packs for £24 https://www.ebay.co.uk/itm/SILVER-BRAZI ... 3307037893

I’ve got the same kit, I tried doing brazing some 67mm copper pipe to ferrules and failed dismally using mapp gas. I couldn’t even get the silver solder to melt!
I’m going to give it another this weekend after watching a still it video on YouTube.

[Swedish Pride]

Yous don't need to hard solder it, just get the right flux and lead free plumbers solder.

[StarkBlood1980]

Yous don't need to hard solder it, just get the right flux and lead free plumbers solder.

What’s the right flux for using plumbers solder?

[Swedish Pride]

HArris stay clean works lovely
https://www.ebay.com/itm/Harris-SCLF16- ... Sw8mpbGwOm

[StarkBlood1980]

HArris stay clean works lovely
https://www.ebay.com/itm/Harris-SCLF16- ... Sw8mpbGwOm

This is the flux I’m using for brazing http://www.jm-metaljoining.com/pdfs-pro ... Powder.pdf

I’m guessing that won’t work for plumbers solder. That Harris stay clean is expensive here in the UK, not sure I can justify £40 on 3 ferrules.

[Boozewaves]

I’ve got the same kit, I tried doing brazing some 67mm copper pipe to ferrules and failed dismally using mapp gas. I couldn’t even get the silver solder to melt!
I’m going to give it another this weekend after watching a still it video on YouTube.

good luck , yes the instructions that you get on ebay make it sound easy to use , it wasnt for me , I was dissapointed ,

Yous don't need to hard solder it, just get the right flux and lead free plumbers solder.

would soft soldering be strong enough to hold a ferrule in place if its at the bottom of a 60 inch column with a stainless tee on it and heavy packing? , I would have thought the smallest tap at the top of the column would crack the ferrule away from the column , thats why I tried to silver solder it

[Pikey]

HArris stay clean works lovely
https://www.ebay.com/itm/Harris-SCLF16- ... Sw8mpbGwOm

This is the flux I’m using for brazing http://www.jm-metaljoining.com/pdfs-pro ... Powder.pdf

I’m guessing that won’t work for plumbers solder. That Harris stay clean is expensive here in the UK, not sure I can justify £40 on 3 ferrules.

This is what we have in UK and Aus -

https://www.ebay.co.uk/itm/Bakers-250ml-No3-soldering-fluid-tinning-liquid-flux-no-3-BAK250/261832452089?epid=6017021168&hash=item3cf66e27f9:g:pbMAAOSwZjhXI3jE

"Harris by any other name" - SAme stuff "Killed hydrochloric acid"

[Swedish Pride]

Harris will deffo work with normal solder.
I built my whole keg, pot still and plater with Harris and plumbers solder exclusively. No issues so far and don't for see any either