Welding tips for stainless???

[Degnol]

I've got a Clarke 100, 110 volt wire welder amd a Miller 250, a bottle of straight Argon and some .023 stainless wire. I need to weld some angle 3/4 x 3/4 made out of 16 ga stainless.
Never welded stainless before, any tips? I know stainless warps pretty bad so I'm thinking stichweld?
He'p me
Ed ???

 

[dylan]

i've only tig welded stainless. it didn't warp any more than mild steel, but ya, stich weld it and keep it cool(keep a damp rag on hand) and good luck!

 

[kupa]

[quote author=Degnol link=board=1;threadid=14453;start=msg135317#msg135317 date=1081455100]
I've got a Clarke 100, 110 volt wire welder amd a Miller 250, a bottle of straight Argon and some .023 stainless wire. I need to weld some angle 3/4 x 3/4 made out of 16 ga stainless.
Never welded stainless before, any tips? I know stainless warps pretty bad so I'm thinking stichweld?
He'p me
Ed ???
[/quote]

I've done a fair amount of MIG welding on thinnish gauge stainless with minimal issues. It welds nicely. As for warping, I haven't had any significant issues. Do you have any stock to experiment on? It does seem to melt a bit faster than mild steel.

Why Argon? I've used tri-mix. It may be cheaper than straight argon.

 

[Degnol]

I had the argon around for aluminum, but was told that I could use it for stainless, also. I have gone to using the 75/25 mix in my big bottle, but around here the mix costs more than the straight argon. I buy from a reseller, so they may have had it priced wrong, dunno. I've also used straight CO2 on regular mild steel and other than a little more spatter, I like the welds.
Thanks and "yes" I'll have some scrap to practice on. Let you know how the experiment tirns out.
Thanks, all.
ED

 

[brian]

you need the tri-mix to mig SS if you're looking to do a half decent job.

any time you have more than one gas in the same bottle, it will cost more.

with mild steel 75/25 is a better chioce.
straight argon will control splatter better, but run a little cooler.

straight CO2 will run hotter, but will produce more splatter.

guess what happens when you mix CO2 and argon?

miging SS can be a little more trickier than steel, but it's far from difficult.

SS will warp way more than steel, if given the chance. on thinner gauges "sugaring" becomes a major concern. when you burn through on SS ugly things happen.

if at all possible set your weldment up so you can run the beads down hill(SS mig works way better this way), it will help on a few issues.

 

[Degnol]

Thanks Brian, but let me ask a dumb question...what is the third gas in tri-mix? And BTW, that's what they told me at the gas store, mixing costs more. I've got a total of about 6" total of welds to make, will I be OK with the straight Argon????
Ed

 

[fergus]

Helium.
What Brian said is the way to go.
Don't forget not to use any iron contaminated wire wheels,grinding discs etc or it will rust on ya.
Passivating the SS with a phos/nitric acid blend can remove tramp iron from the surface but not so much if it is ground in.

Good Luck.

todd

 

[brian]

[quote author=fergus link=board=1;threadid=14453;start=msg135845#msg135845 date=1081522502]
Helium.
What Brian said is the way to go.
Don't forget not to use any iron contaminated wire wheels,grinding discs etc or it will rust on ya.
Passivating the SS with a phos/nitric acid blend can remove tramp iron from the surface but not so much if it is ground in.

Good Luck.

todd
[/quote]

actually any wire brush used MUST have SS bristles and have never been used on anything containing carbon. even if it's a SS brush that was used on carbon steel, it can not be used on SS. while the SS it's self won't rust, the carbon deposits on the SS will rust giving the illusion that the stainless is rotting.

if anything you can try using the 75/25, it won't be pretty but i think that it will work.
IIRC the helium is there just to increase the arc temp(there's only like 5% in a bottle).
about the only thing straight argon is recommended for is TIGing(steel,SS and alum) and i think a cheaper way to mig alum.

the other day a guy at work was SS flux coring some stuff with 75/25, and could'nt figure out why it was'nt running right, it worked, just not the right way to do it.

 

[brian]

and what kind of wire is it?
308, 309?

 

[Degnol]

The wire I have is Forney ER308L, says it requires Argon shielding gas, .030. I've got some scraps to practice with, and will report back.
Man they're proud of that sh!t, $25 for a 2 lb roll!
Thanks,
Ed
BTW I'm planning on using the 110v welder, it is easier to change the spool. Or should I use the Miller 250?

 

[brian]

250