Soldering Stainless steel

[Scut_Monkey]

I'm still kind of confused. Is this an alternative to have the pieced TIG welded on? I realize it wouldn't be as strong but what is the draw back when this seems far less labor and tool intensive?

 

[wyzazz]

It is an alternative, but you hit the nail on the head. It is definitely not as strong. Soldering melts a dissimilar metal in between the two pieces, welding "melts/fuses" them in to the same piece of metal.

 

[Scut_Monkey]

It is an alternative, but you hit the nail on the head. It is definitely not as strong. Soldering melts a dissimilar metal in between the two pieces, welding "melts/fuses" them in to the same piece of metal.

So is soldering strong enough for our typical application or is it kind of a gray area? Do we need to worry about a propane/NG burner softening the solder on something like a kettle drain?

I only ask because this is something I can do where as TIG welding I cannot.

 

[BargainFittings]

From my personal experience it is strong enough. It helps to have a tight fitting hole. If you are using a very thin kettle then you can always solder in some washer(s) to beef up the hole a bit.

The flame could melt the solder if you dry fire the kettle. You should not do that anyway as it can melt the seals in your valve.

EDIT: Guess I was just a little slow. BrewBeemer beat me by a minute

 

[BrewBeemer]

If it's fired dry by gas the joint may get hot enough to melt soft solder, silver solder would be the minimum I would use. With electric you'll never get the soft solder joint hot enough to melt the solder. If you backup both sides of the keg with soldering a washer it will strengthen this coupling or pipe stub thru this soft solder joint.
Years ago in a hurry to brew I soft soldered nipples thru kegs (leaded solder no less back in 78) and a couple times the nipples with valves did break loose being lifted or banged on the valves caused these joint failures.
Do it once right not cutting corners or costs and you'll be rewarded with many trouble free years of brewing.

 

[BargainFittings]

I can definitely see that happening. I managed to crack the solder joint on my kettle. I shimmed it with a washer and all is well.

 

[Ludo]

I shimmed it with a washer and all is well.

How can you solder a fitting on a washer soldered on a kettle without melting the solder...

I know it sound weird but I just don't get how you solidify your kettle without damaging your previous solder.

Hope it make sense!

 

[Scut_Monkey]

So it sounds like as long as you aren't heating up a keggle dry or whacking the fittings off something they are relatively the same as a welded fitting. I think I may have to give this a shot someday when I decide to put a drain on my keggle. Thanks for bringing this idea forward.

 

[BrewBeemer]

How can you solder a fitting on a washer soldered on a kettle without melting the solder...

I know it sound weird but I just don't get how you solidify your kettle without damaging your previous solder.

Hope it make sense!

Scut; no solder joint can match a Tig welded joint, silver solder would be way stronger than soft solder.

First I would add a curve to the washers to match the radius of the keg which is a 7 7/8" radius or 15.75" diameter, kegs vary in diameter by manufacture. The thinner the solder joint layer the the stronger the joint will be. Clean the washers, keg, nipple or coupling (your choice) with 80 grit sandpaper allows for more tooth for the solder to adhere. Brush all surfaces to be soldered with stainless acid flux, assemble with applied pressure clamping the washers to each other one inside one outside the keg with the nipple or coupling aligned. Apply heat, when it's hot enough the solder will be pulled into the fitting and washer by capillary action. Using two washers will increase the nipple or coupling strength vs just thru the keg alone. I would silver solder if Tig is out of the question or budget.
Dry firing a keg with gas it can happen i've done it a one of those Oh Chit monents with the fitting hanging from the keg. This is the reason why silver solder is the minimum I would ever use on a fitting with Tig the first choice.

Scut; what you doing up this late your right coast i'm left coast?

 

[BargainFittings]

How can you solder a fitting on a washer soldered on a kettle without melting the solder...

I know it sound weird but I just don't get how you solidify your kettle without damaging your previous solder.

Hope it make sense!

I cleaned the joint up, refluxed everything and soldered on the washer.

I have to agree with Brewbeemer on the possibility of it melting with gas and dry fire of the keg / kettle.
Weldless fittings do not have this problem either. Of course you could melt the o-rings by dry firing a kettle.

In a perfect world we would all live next door to a master tig welder or have our own tig equipment!

 

[Ricand]

Mine are silver soldered and I beat the pookey out of them with no trouble. Just a personal experience here, YMMV.

 

[Ludo]

Didn't think of putting two washer on each side of the hole. That would be heavy dutty!
I don't want to insist but there's only a little thing I don't understand...
Once you have soldered the two washer, you are ready to solder the fitting, don't you? So you let the washer cool off a little and re-clean the surface for the new fitting with flux and all. Once it's done, you re-apply heat to the joint and, at this moment, are the solder of the washer's gonna melt...
Hope it make more sense, it may be hard to understand on my last post.

 

[pickles]

Ludo, couldn't you assemble the whole thing and solder once?

 

[Ludo]

That's about what I'm asking, is it a two step operation or is it doable in one?!? Don't know, I never did, but it seem hard to do in one, no?

 

[BrewBeemer]

I cleaned the joint up, refluxed everything and soldered on the washer.

I have to agree with Brewbeemer on the possibility of it melting with gas and dry fire of the keg / kettle.
Weldless fittings do not have this problem either. Of course you could melt the o-rings by dry firing a kettle.

In a perfect world we would all live next door to a master tig welder or have our own tig equipment!

I have one of these in my shop for my personal hobby projects. A fully loaded freebie that paid for itself within 6-8 months welding for my contractor on the side at home. Today with the wet torch, cooler plus tanks to get started would cost me $9K after taxes out the door.
http://www.millerwelds.com/om/o352f_mil.pdf

Again but with my copper cashed in for a 251 Miller Mig with 30A spool gun with bottles and support equipment.
http://www.millerwelds.com/om/o1326p_mil.pdf

http://www.millerwelds.com/om/o1213u_mil.pdf

I'm now in the hole on this last welder purchase by $324 as I added a wide lens Speedglas 9000X hood and another pair of 280 cu/ft owner owned bottles to match my Tig bottles. Call it my retirement toys like my Bridgeport mill lathe plus the Hypertherm Max 20 Plasma for $125. Lucked out on that find in great condition that checked out ok by my Miller repair facility friends. They handled Hypertherm repair at one time. Get this the test and check out cost me two 6 packs of Miller Light.
love those thech repair guys the past 23 years.

 

[BrewBeemer]

I cleaned the joint up, refluxed everything and soldered on the washer.

I have to agree with Brewbeemer on the possibility of it melting with gas and dry fire of the keg / kettle.
Weldless fittings do not have this problem either. Of course you could melt the o-rings by dry firing a kettle.

In a perfect world we would all live next door to a master tig welder or have our own tig equipment!

Wayne; if it were me and I had no other way but to go weldless the only way I would go that route would be to machine two large diameter washers 1/4" thick then add a recessed or counterbored pocket to lock in a high temp orange "O" ring. These thick washers would be curved after machining to match the kegs radius. This way the "O" ring is preloaded or crushed without spitting out with these thick washers being tightened down for a solid metal to metal contact making for a strong solid fitting to the keg.
Even the couplings I see they need no washer just counter bore the coupling to lock in the "O" ring and tighten down metal to metal making for a solid fitting without flexing on the "O" ring or the valve turning. Make it fail safe built once. JMO's

 

[skarude]

This thread has been very helpful to me and I wanted to share my first attempt at soldering a copper ground lug to my hlt to be. The hardest part was keeping the piece from moving around since it sits on top of the barrel.

Hopefully the second one will be a little straighter, but it seems very strong and should do the trick to ground my element.

 

[pickles]

Ooh I like the idea of adding grounding lugs, I'm adding those to mine.

 

[BrewBeemer]

You want to get real tricky as I brought this up once and got a reply yes you can Tig copper together with stainless filler rod. It looked like a NASA quality weld. Yup a totally different mix of metals as it was a topic I brought up over a year or two ago and one member on the Miller Welds Forum proved it can be done. Were talking Nuke class of welders on down to newbies that hang around this forum for support help and talk about great support group no secrets or I did this photos without explaning how it was done. A very good group of members. I've learned a lot from them and this www.millerwelds.com forum. With your narrow copper ground lug that's soft and can be twisted around just by tightening the screw I would think silver solder for a stronger bond comes to mind, just an idea. I've broken off soldered items many times in the past.

 

[skarude]

For what it is worth I did use silver solder. In fact I got this kit from a local hobby shop. I went this route because buying this flux from a welding shop is very expensive. I used a cheap butane soldering iron with a torch attachment to heat it which worked great. One thing that may have helped was that I had actually tried this once before a while ago an failed but it sort of tinned the area bellow the lug. I can tell you for sure that this lug will not twist just screwing it down. It is rated for #4 - #14 wire so it is pretty heavy duty and the joint is very solid.

 

[BrewBeemer]

Sounds like you had it planned out plus great hearing you used silver solder your good to go.

 

[skarude]

Yeah figuring out how I wanted to ground the rig has been my biggest question. I didn't want to drill a whole for a bolt and was not really thrilled about cutting out copper sheeting. I hope this holds up well because it seems like the cleanest solution to me.

 

[pickles]

Brewmoor,
Did you use safety silv 56 or 45? You first post said45 then later you said 45 wasn't good, just curious. I am gonna us 45.

 

[ScubaSteve]

So can anyone else comment on the durability of this method? I'm kinda depending on this being a viable option for my rig....otherwise it's off to the welder and I just know he's gonna price gouge me

 

[seanmichaleen]

With the Stay-Brite 8 solder, is 1/8" going to be too thick to do decent work? It seems to be more reasonably priced than the other sizes.

 

[P-J]

I talked with a friend yesterday about soldering SS. He was having difficulties soldering a fitting to an aluminum kettle. He will try again this morning.

One of the things he mentioned was this forum as he participates here. He mentioned this thread so I took a look this morning and decided to join and post a comment.

I've been using StayBrite-8 solder and StayClean liquid flux for years. I think it is a great solution for us brewers in fabricating equipment.



This is just one example of the possibilities (click the pix for the inside view)

Another is a fitting on a hopback that I fabricated:



The image is the dry fit - click it to see the finished joint.

One of the things I like about StayBrite-8 is that it has a plastic range that allows me to easily fill gaps.

Anyway, I figured I'd show off a little.

Thanks.

 

[Scut_Monkey]

Very cool pics. I'll have to try this for my keggle. As of now I have no drains or anything installed on it simply because I don't want to pay for welding and want to do it myself but don't have the tools or skills. Soldering I can do! Awesome thread.

-Prosted

 

[pickles]

I tried using Staybrite 8 And Stayclean paste flux and can't get a good joint. I sanded and sided the area , cleaned with denatured alcohol applied flux to both pieces,assembled the fiiti g in a tight fitting hole, heated and applied solder but it just beads up. I'm using mapp gas canister. Should I try to tin the pieces first or is the secret the liquid flux? I've sweated plenty of copper joints but only with propane.

 

[GreenMonti]

I tried using Staybrite 8 And Stayclean paste flux and can't get a good joint. I sanded and sided the area , cleaned with denatured alcohol applied flux to both pieces,assembled the fiiti g in a tight fitting hole, heated and applied solder but it just beads up. I'm using mapp gas canister. Should I try to tin the pieces first or is the secret the liquid flux? I've sweated plenty of copper joints but only with propane.

Yea, You need different flux. You need the liquid flux. That's why its beading up.

 

[BrewBeemer]

Cut muriatic acid has always been my favorite, this plus not overheating the joint
if so start completly over with sanding bright again or else you'll ball up like soldering on glass. Done properly stainless solders like copper draws in the solder when it's ready. I use a propane torch or another torch designed for natural gas and compressed that I can silver solder with vs going to O&A. Quick hand eye work also helps, leave the bier alone until done.