# Arc Welding Stainless



## Moray (12/6/11)

I would like to weld a couple of sockets to a keg to convert it into a mash tun.

If I use 316 stainless electrodes can I do this with an arc welder?

Are there any tips or tricks that might help me do this.


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## tavas (12/6/11)

Technically you could. You just need to be aware of blowing holes in the parent metal. TIG is usually preferred.


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## amiddler (12/6/11)

Moray, Hows your general ARC welding skills? Stainless is less forgiving than mild steel and as tavas said holes are easily blowen into the parent metal. You also want to clean the welds and ARC leaves a large heat zone to clean. 

If you can drill the holes and have the sockets ready a local TIG welder could weld and clean 2 or 3 sockets in about 15 mins. The ones I know do such jobs for a carton which is nothing for how perfect the welds should come out.

Drew


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## yardy (12/6/11)

I'd go with Drew's suggestion but if you decide to weld them yourself, concentrate the weld pool onto the socket and wash it onto the parent metal or you will blow holes in your keg.

cheers


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## Gavo (12/6/11)

Done similar on boat exhausts before, here are my 2c



use a small dia welding rod
Practice on similar thickness metal first
preheat the rod by striking the arc on another piece of steel
concentrate heat on the thicker item
use short stitches and overlap them and allow time for each stitch to fully cool. Stainless retains its heat longer than mild steel and will blow through faster. (won't be as tidy but will be less likely to blow through)
let the sockets protrude so you need to do a fillet weld
watch out for the slag as it cools - it will literally pop of and can pop a very hot piece of slag straight into you eyes
sand the area thoroughly afterwords until it is stainless cover and shiny again - this will effectively stop it from rusting
Have fun. Personally I love welding stainless, it's great stuff to weld when you get used to it.

Cheers
Gavo


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## chappo1970 (12/6/11)

yardy said:


> I'd go with Drew's suggestion but if you decide to weld them yourself, concentrate the weld pool onto the socket and wash it onto the parent metal or you will blow holes in your keg.
> 
> cheers



Agree with all that's been said especially Yardy here. Arc can be done and done well, but you would need to be better than just average in my opinion. If I can add my 2c you want the thinnest rod you can get IIRC it would be 2mm. Clean the area thoroughly and as Yardy has said work your weld pool from the socket to the parent metal but you'll need to be careful and make sure you have a good steady power supply. You don't want any surges as arc welding stainless is not forgiving. Also be sure that your pot is 316, as most kitchen grade wares are in fact 304 which is not a biggy but there is a certain rod to buy that is great to use for 316 to 304. Also have a look at braizing the sockets on with an Oxy. Your local engineering supply joint should know what you need.

Good Luck

Chap Chap

EDIT: Agree with Gavo there and well said mate.

Also a must is some Pickling gel to passivate the weld.


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## Norto (12/6/11)

Mate I have just welded a couple of couplings in my kegs and i just used a normal gasless mig with normal flux cored welding wire in it. I did use some "commweld" flux that they used when silver soldering, I covered the whole area I was about to weld and like the others guys have said I concentrated the weld into the couplings as they are the thickest. I did not blow any holes and have done a leak test and all good so far and believe me I am not the best welder going.
Goodluck 
Norto.


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## MHB (12/6/11)

Do you mean normal as is in mild steel wire, if so its going to rust which rather undermines the whole point of buying Stainless Steel pots and fittings.
Far better to Stick, TIG, MIG with SS wire (havent seen gasless SS wire) or Braze or even I think go weld-less.
MHB


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## amiddler (12/6/11)

yardy said:


> I'd go with Drew's suggestion but if you decide to weld them yourself, concentrate the weld pool onto the socket and wash it onto the parent metal or you will blow holes in your keg.
> 
> cheers



I wish I would listen to my own advice Yardy. When I put my sockets in I ARC welded them in blowing holes and ended up with that much heat the sockets were an oval shape. Alot of thread tape was used to get it water tight. Some time in the future I will be re-making the brewery but in the mean time it works.

Drew


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## yardy (12/6/11)

I stick welded my whole system, including the bung in my Kettle but it's about 1.2mm so it wasn't too bad, got the TIG at work but I'm too lazy to bring it/gas home..


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## Moray (12/6/11)

Thanks everyone for your advice.

I've got a spare socket and have the cut off top from the keg to practice on.
I was thinking of getting these rods, as they say they are suitable for 304 (keg) and 316(socket)
http://www.bobthewelder.com.au/product.php...=151&page=1

I think I'll try the practice socket and see how it goes, if it's no good I'll follow Drew's advice and find someone to tig it.


How important is the pickling, is it just for appearance sake.
can I use a flap wheel instead to clean up the welds?


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## abyss (12/6/11)

Gday Moray, Just use 2.5mm stainless rods and set your welder on about 50 amps to start with,do the weld in about 4 to 6 stages on opposite sides of the socket,aiming the rod towards the socket and letting the metal cool down between each tack.


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## Moray (28/10/11)

Well I've now succesfully done it.

I used 2.5 mm rods and did it in six tacks per socket. I gave it a few minutes between each weld, and did each weld on opposite sides.
I also screwed in a length of threaded pipe whilst still hot to ensure it still fitted.

It was pretty easy, and didn't blow any holes  . It also holds water so all good.

Here are a couple of pics.





I read the bit in Palmers book about passivating, and reckons use a scotch pad and stainless cleaner.
I'll give it a go on the weekend.

The welds aren't as fine as you would get with tig, but they are functional and don't look to bad.

cheers
Moray


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## Cocko (28/10/11)

I can't believe you did it so quickly!

Do you have your welder at your computer?


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## peaky (28/10/11)

yardy said:


> I stick welded my whole system, including the bung in my Kettle but it's about 1.2mm so it wasn't too bad, got the TIG at work but I'm too lazy to bring it/gas home..



I TIG welded mine but I took my pots to work early in the morning and stashed them under the bench. Once the boss man is safety tucked away in his office out come the kegs..... :lol:


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## peaky (28/10/11)

Moray said:


> I also screwed in a length of threaded pipe whilst still hot to ensure it still fitted.



Nice work, but be careful of this. If you thread a fitting into a freshly welded stainless socket and leave it there until the socket cools, you'll never get the fitting back out. We just leave them to cool and run a tap through if necessary.

You'll only ever do it once.......


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## yardy (29/10/11)

peakydh said:


> I TIG welded mine but I took my pots to work early in the morning and stashed them under the bench. Once the boss man is safety tucked away in his office out come the kegs..... :lol:



I work in an alumina refinery so it's a bit difficult to cart kegs onto site  

you a boily peaky ?

cheers


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## peaky (29/10/11)

yardy said:


> I work in an alumina refinery so it's a bit difficult to cart kegs onto site
> 
> you a boily peaky ?
> 
> cheers



Not a boily by trade but have been welding/fabricating on and off for 15 years. Have done a fair bit of TIG stainless over the past couple of years and I've had the good fortune of working with some top notch boilermakers. It makes a big difference if you're being taught by someone that is really good at their trade.


edit;spellingetc


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