Stainless welding options

dstig1 · Sep 28, 2014

So I am thinking ahead to next year.

I am going to weld up some SS railings and mesh for a 3 decks/porches on our new house. My power supply is a Miller XMT304, run on single phase 220. It can do MIG, TIG (DC only) and stick. So far I have only done MIG with it on plain steel, though I did a bunch of stick on my Lincoln stick welder before that. I have a 12 or 15' 300A Tweco gun on it (I think it is 12') and currently a C25 gas cylinder, but I also have a helium cylinder I picked up from CL for almost nothing that I might convert to something else as needed. No spool gun. I am going to have to weld a good number of inches of SS. I could set up TIG, but know it is slow. Can I reasonably feed SS through my current gun or do I really need a spool gun? Not really considering stick SS in this case as I don't want to fight with the slag. Obviously I would need a new tank of gas to MIG the SS too (Trimix?).

I guess I'm just looking for suggestions and discussion at this point. Then I can figure something out from there. I guess the big question is TIG vs MIG and if MIG then spool gun or not? I kinda hate to get a spool gun for this as the ones that are compatible are pretty pricey. Just looking to get thoughts from the collective...

Thanks!

Blade Breaker · Sep 28, 2014

No spool gun needed . Just get the wire and a tank of stainless mix 90%He/7.5%Ar/2.5%CO2. Your standard drive rollers and liner will work fine. Guessing .035 wire is what you have in mind. Xmt runs ss great.

Let me know if you need anything else.

Gary Fowler · Sep 28, 2014

If and only if you can do pretty TIG welds, that is what I would use. The welds on porch rails will always be in sight so they need to be pretty. A TIG weld when done right is the best looking weld and will use less $$$ worth of gas. It is a bit slower than MIG but I think the quality and beauty will win out for the vote.

dstig1 · Sep 28, 2014

BB- Nice to know it will run through the gun as is. Though I am probably due for a new liner. Bought this setup used a few years back at auction and they had been running fluxcore or dual shield or something nasty through it.... But getting back on topic... That may help the decision a lot as if all I need is a new cyl of gas and some wire, that may be just the ticket. 035 is what I was thinking would be about right. It seems to be a sweet spot for a lot of stuff that one can do at home. Works on 12 ga up to 1/2", more or less...

Gary - My TIG experience is all of one evening. My welding class a couple years back we had some time the last day and the teacher was very helpful and showed me how to TIG and I did a couple 2" cubes out of steel and SS. Mixed results... I could get better at it if I invested in it with some time, and I do want to, but time is the big problem with the house build. Coupled with my realization that TIG is quite a bit slower, pushes me towards MIG if it works, and per BB's points, that looks like the best option for me.

Thanks for the input! Curious what others have to say...

mrmikey · Sep 28, 2014

I'm with Gary, Tig. It is substantially slower but when you take into account the finishing time and the finished appearance there's no comparison, just my two cents worth....Mike

nybirdman · Sep 28, 2014

I have done tons of Tig Stainless in breweries and paper mills on pipe.Only way to go for a quality looking job.Mig may be faster but you are going to have a lot more clean up afterwards(splatter).

Gary Fowler · Sep 28, 2014

Cleanup is the big killer for having nice looking welds. My employer prior to me retiring did some production studies as to manhours required to do TIG root & hot pass welds on carbon steel vs using stick rod, then grinding out the impurities on the root pass and running a hot pass with carbon steel electrodes. It was found that time wise, dollar wise also figuring in consumables, it was much faster and much better quality to run TIG than stick. MIG quality is not going to be there either. I always said that a malfunctioning MIG gun can make a mess in 1 minute that will take you one hour to grind out.

If you can weld everthing flat or nearly so, just about anyone can make a descent TIG weld and with just a couple hours practice you can be turning out some pretty fillet welds on the stainless. YES it is a bit slower but that is too your advantage in making a pretty weld unlike MIG where you have to move pretty fast and on small pipe that means fast rotation of the MIG gun to keep the wire feeding at optimum angle or you are going to have a lot of grinding to do for cleanup.

Gary Fowler · Sep 28, 2014

OH yeah, lets not forget the cost of equipment for MIG vs TIG. A good TIG torch with 25 foot hose can be bought for less than $200 with regulator. What is the MIG gun going to cost (unless you already have one that is)

dstig1 · Sep 28, 2014

Well, yes, I already do have a MIG gun, which is part of the equation. There would be minimal additional cost to adding SS to MIG, but more if I were to go TIG. But on the plus side, I do want to get TIG capability for the long run, so that is a factor here too. Maybe this is the time to do it... I hadn't thought about spatter with SS MIG as I see so little currently on steel. That is a good point.