At wit's end. (Soldering SS)

[T-Pee]

Before anyone even THINKS of telling me to do more research, I've been through way too much already.

I'm simply trying to solder or braze SS ferrules into my 1-1/2" copper column. I've tried about everything but welding and can't get soft solder or silver brazing rod to stick to the SS ferrule. I've been through two $10 cylinders of O2 already and have gotten nowhere. I've used a new propane torch with acid flux and lead-free solder. Bottom line...

I'm thoroughly pissed and don't know where to go from here. In the meantime I have three ferments just sitting and a column in three pieces in the shop.

tp

[StillLearning1]

If I were you I'd go to the liquor cabinet and wait for a good reply here

Sorry can't help ya. I have no idea how I eventually got mine to stick. Beginners luck I think.

[BayouShine]

I'm in the process of building a 2" column right now. I wasn't too confident with soldering SS, so I ordered a SS Tri-clamp ferrule to 2" NPT adapter from St. Patricks of Texas. I'll solder on a copper adapter on the column end and screw those together with ptfe tape. Seemed like a logical choice to get around soldering stainless. The 2" adapter cost $30.

[humbledore]

Did you manage to rough up the ss first? Even with good flux and solder it won't stick unless you do.

[T-Pee]

Dremeled it good with a rough sanding barrel.

tp

[humbledore]

What brand of solder/flux? The Harris stay bright 8 and stay clean flux makes it easier. And a mapp torch. Edit: I was able to do it with basic silver solder and flux but it was a bitch. And ugly, the thread is on here somewhere.

[pfshine]

What kind of flux did you use tp? When heating that type of joint keep the heat on the copper and barely hit the as. I use uni 450 and never had a problem with ss. Just get it hot enough for the solder to flow. The 95 5 stuff.

[Kegg_jam]

Radnor stay-clean is what the guy at my local welding shop sold me. Has worked good so far. Getting ready to do some ss ferrules myself. I know that too much heat does me in. Like if the flux gets blackened at all.

[Saltbush Bill]

As has already been suggested the right flux helps, Ive also found the higher the silver content of the hard solder the easier it is.
My first attempts were pretty rough but got better with practice.
A couple of things I learned as a I went were to heat the stainless mostly...you need to get it pretty hot, the heat will soak from it to the copper.
make sure both copper and stainless are nice and clean and are coated in flux before starting.

[bentstick]

Yes sir SBB, clean and even heat have got them to stick easy but the copper will expand more than ss is some thing to think about,solder wil fill tight joins not sloppy's

[corene1]

Dremeled it good with a rough sanding barrel.

tp

Sometimes the glue that holds the abrasive to the barrel will get imbedded in the stainless and the solder will not stick to it. Take and use your dremel to sand the ferrule nice and clean then wire brush the heck out of it with a Stainless wire brush. Clean the copper up nice and clean. If you are using a low temp solder use a good quality acid flux , I like Harris Stay clean . make sure all the joint is covered and start applying the heat to the copper and let it transfer to the stainless. If the stainless get too hot the solder will just slide off of it. Remember copper dissipates heat quickly and stainless steel holds heat so you have to keep most of the heat towards the copper. While bringing the heat up it is OK to brush another coat of flux to the joint just improve the cleaning action. Don't put heat to the solder itself let the material melt it. If you are using a high temp silver solder you will need a high temp flux that won't break down at the higher temps that are required. 45% silver solder melts at 1125 as a reference. Stay brite 8 melts at 525. If you keep having problems let me know , I will fix it for you.

[T-Pee]

Using Oatey Safe Flo silver solder and Alpha 51022 liquid acid flux.

I'm about to the point of just buying a foot of 6 gauge copper wire and a 2" hose clamp and doing ez flanges and I HATE something like this beating me especially since I've been soldering and brazing for 30 years to the point of having a nuclear qual in soldering.

tp

[Davel]

Hey TP another trick you could try is to sweat solder on both piece separately. Put them together with some flux and gently put the heat to them with a good propane torch.....too hot of flame or to quick of heat up can cause the flux to carburize and not effectively clean the surfaces......being a welder by trade this trick has worked for me when other things haven't.......good luck.

[T-Pee]

Ok. I'll reclean everything, tin the parts and try a low temp sweat-together tomorrow. They're pretty loose with the ferrule easily fitting inside the column.

tp

[Maritimer]

In applying the Dremel tool to grind the HSS, you will run into a problem if the grinder is silicon carbide. The silicon carbide dissolves in the HSS, which might be causing the problem. Here is a post on homemachinst:

Silicon carbide wheels should not be confused with aluminum oxide wheels-----which are the wheels of choice for grinding steel----the reason being that silicon carbide readily dissolve in steel at heat----thus, in spite of being harder than aluminum oxide, it doesn't grind steel as well-----failing almost instantly. That's the same reason diamond is not recommended for grinding steel. Run them slow enough, it's not a problem.

here: http://www.chaski.org/homemachinist/vie ... =4&t=77277" onclick="window.open(this.href);return false;" rel="nofollow but I can't seem to get the URL for the particular post.

M

[Twinrivers]

sorry for the headache you are experiencing. If you lived closer I would be happy to tig that thing up for Ya.

[T-Pee]

In applying the Dremel tool to grind the HSS, you will run into a problem if the grinder is silicon carbide. The silicon carbide dissolves in the HSS, which might be causing the problem.

Nope. Basic aluminum oxide sanding drum.

Appreciate the thought, Twinrivers.

Thanks for everyone's patience on this one. I also read the other soldering thread on this page and checked out the links. At this point the ez flange would have been a lot less annoying and cheaper.

tp

[johnarms]

I went through the same PITA with stainless, even tried to electroplate copper to the stainless. finally went to easy flanges and havent looked back, they are easy, and they work well. I wrap the 1/4" around the pipe a couple times, run it through the band saw, straighten the link, sand the ends till they fit the pipe well, then I use the power of stainless not taking solder... I use a pipe clamp to secure the ring around the pipe after flux. solder and whack it into shape with a small tack hammer. sounds like alot, but takes about fifteen minutes. Did three of them this AM on a build for a friend.

[firewater69]

TP, i think i still have some 30% silver alloy i could send you if your interested. i use it on the last s.s. / cu joint that i did. it easn't great but it did work.

[thisguy]

I was equally frustrated trying to get my SS nut to the SS boiler for my element and my SS nut to SS lid for the adapter to go into.

What I did was pretty much treat it like copper, even though its completely different....
I used your average propane torch, SS Flux, and normal 2% silver solder. Pretty sure, from what Ive read, watched and experienced, that the key to getting SS to SS is the flux and making sure the SS is SPOTLESS.

I used propane cause it wont burn the flux as fast.

The method I used was use LOTS of flux. Lots and Lots of flux. I also made a ring of solder and put it underneath the nut I was trying to solder. So apply lots of flux; then dont heat the nut, or in your case the ferrule directly, instead start making circles with the torch around the component to be soldered (a few inches away from it) working slowly towards it, let the heat transfer to the ferrule. Then if i remember right, once i circled to the component I focused the flame on the component, make sure to keep the flame moving and away from the solder. So its not the direct flame that starts melting the solder, but the heat of the SS. Eventually the solder melted and took to the SS. It took me about 4 tries and 2 different lids/pots to get it, but it worked and is still working without leaks. Just make sure your using SS flux and the SS is scrubbed absolutely clean if the flux gets burnt to it. Im guessing it was beginners luck.

Hope that helps TP...

[Hound Dog]

Damn TP, you're making me nervous and I haven't even started. I just got some SS ferrules that I planned on putting into my column. Have to expand the type L pipe I am using so they will fit first. Like you, I have never soldered copper to SS though. Hope this works.

[T-Pee]

"There comes a time in every project when you just shoot the engineers and begin production."

Apologies to all the engineers out there but I'm an old fixit guy and I finally said " it" and went with what I know. To everyone, thank you for the help. To "johnarms", YOU BETCHA. EZ flange time.

The only mistake I made was using 4ga copper wire instead of 6ga which made me grind a relief bevel on the underside of the flanges so the clamp would fit but it turned out nicely. Tomorrow the cleaning runs and then back to cookin'.

I put this glass at the junction where the packing will stop above the reflux coil. The coldfinger comes down to just below the top flange. I use one or both depending on what I'm doing and now I'll be able to see what really is happening in this column. I don't do AGs yet so I'm not concerned with a puke but right now watching for flooding is my main concern. The second one will eventually go in just above the boiler.

Here's a few pics of today's efforts.

Setting up for soldering

Soldered

Cleaned up

Installed

Complete and ready for cleaning runs

tp (and the end of a long day)

[Kegg_jam]

So thanks to your misfortune I was able glean some information from this thread to help me through my ss ferrule experience.

Turns out that gently tinning the ferrule first worked for me. I tried doing an all in one step but that was a no go.

Your easy flange looks great by the way...

[T-Pee]

I think ya need to do some more reading.....hehehe " as I hide behind a brick wall"

Oh, I'm not done with SS yet. I still have the ferrules and I'm going to continue getting it right. In the meantime though, my still is back in one piece.

tp (who knows where our Global Mod lives)

[thumper123]

Lots of good advice on this thread. I'm with corene1 about the Harris StayClean - it's an acid flux and it's the best for SS or SS to copper. One thing I've found when soldering SS is that cleanliness is next to Godlyness. I use a SS wire wheel on a dremel tool after I break the surface with emery to remove any foreign polutants. Thoroughly wipe down surface with alcohol, prepsol or acetone BEFORE you sand anything. This an old precaution used by body repairmen, and you may not gain anything from it, but it never hurts in case there is some oil or contaminant. Tin both sides of the pieces to be joined where applicable then join mechanically, heat and fill. Watch the heat as suggested above. In one of my early attempts, I just couldn't figure out why the solder was rolling right off the SS - too damn hot - I was using MAPP gas. I switched to propane, and reverted to basic soldering principles - let the hot metal melt your solder. You then have the right temp. I've found that even a very small amount of silver makes a difference on SS. It flows much better. Also, after prepping the SS, solder right away. The oxidation that protects the surface of SS from corroding begins to reform quickly.

It will help to practice on scrap SS and scrap copper tube onto SS first.

[johnarms]

where did you get the glass section? nice easy flange btw. those pipe clamps work like a charm eh?

[S-Cackalacky]

Congratulations T-Pee on getting your still put together with the easy flanges. Keep practicing the ss to ss. I did it once (not a flange) and it was a real pain to get it right. Now I avoid it whenever possible which is to say, I'll probably never do it again. Just kidding. It does take a little more practice than copper to copper soldering, but once you get the hang of it and the stars align and meditation gets you in a good zen state of mind, piece of cake.

There's a lot to be said for the tinning technique. Once you're successful with the tinning, you can be assured that you have the two pieces well prepped.

[Jimbo]

Looks like a perfectly engineered solution to me. bang! ship it.

[Hound Dog]

Quick question for the better educated in this..... Would pure silver be better than silver bearing solder? .999 silver is less than $18/oz spot now.

[T-Pee]

Considering the fact that I seriously doubt that I'll need to solder SS since the EZ flange worked so doggone well, I'm not much in the mood to flog this dog much further.

Today's sac run was awesome. More on that in another thread titled "Sight Glass fun!"

Thanks all!

tp