Mig welding SS and beyond.

StokedOnSpokes · Sat Mar 07, 2015 5:56 pm

Ok, I new here and am not going to pretend I know jack about welding. I have a Lincoln Mig 140 c with no gas (so it's a wire welder now). I've done hobby work with it and that's about it.

Now, I need to run two beads on my motorcycle's crossover pipe, which has two cracks. I contacted Lincoln and it was suggested that I use tri-mix gas and stainless filler wire. I get that. I was first going to weld it with my flux core and clear coat the bead to prevent rust. I was told that the weld will contaminate the SS and there will be cracks along the new welds in no time.

So I am willing to buy a bottle w/tri-mix to do the job but was hoping I could use the gas with other welding needs, like welding mild steel. Can I do that? I don't want to waste the gas or go through hassle of refilling it with different gas after doing one ten minute job.

What are my options? Outsourcing the weld is not one of them. I want a bottle and gas for other work too.

Thanks.

AKweldshop · Sat Mar 07, 2015 6:03 pm

Can't speak for it, but it's out there.

http://www.ebay.com/itm/035-308L-FCO-Ga ... 2eb897979c

Sat Mar 07, 2015 6:38 pm

StokedOnSpokes wrote:Ok, I new here and am not going to pretend I know jack about welding. I have a Lincoln Mig 140 c with no gas (so it's a wire welder now). I've done hobby work with it and that's about it.
...
So I am willing to buy a bottle w/tri-mix to do the job but was hoping I could use the gas with other welding needs, like welding mild steel. Can I do that? I don't want to waste the gas or go through hassle of refilling it with different gas after doing one ten minute job.

What are my options? Outsourcing the weld is not one of them. I want a bottle and gas for other work too.

Thanks.

Yes, you can weld mild steel with tri-mix. I actually prefer it, when I have the option... It's a hotter weld for the same settings, and you also have the ability to "spray-arc" with it (a flat-position only method that makes beautiful deep-penetration welds).

Steve S

Superiorwelding · Sat Mar 07, 2015 8:19 pm

Welcome to the forum! Looks like a good little prject. I will propose another side of the tri-mix. Wanting to purchase a tri-mix (which in this case would be 90% helium, 7.5% argon, 2.5% co2) is great but the expense for the few inches of weld there is was out there. Steve, bless his heart

, gets his mixes for free (employer) so it makes it convenient for him and yes it will help increase your arc energy. I would advise against purchasing a tri-mix bottle for such a small repair BUT other gas mixes are not advised with the SS welding so you have a few things to consider.

You could purchase a 75% argon/25%CO2 mix which will work great with your machine on all your other projects or even a 90% argon/10% CO2 but keep in mind anything over 3-5% CO2 (depending on the SS) content will actually reduce the corrosion resistance and introduce carbide precipitation. Since this is a manifold that will see high heat cycles the carbide precipitation will be a concern for you.

I recommend a 98% argon/2% oxygen as this will keep you well below your max oxygen content (which is 3%) and allow you to use this gas on your other projects. The added bonsus will be the dramatic decrease in purchase price.

Here is a article from Lincoln Electric for your interest as well.
http://www.lincolnelectric.com/en-us/su ... lders.aspx
-Jonathan

Sat Mar 07, 2015 10:37 pm

I won't argue about 98/2 being a great choice. I would not have thought of it, since I don't use it.

Jonathan, "bless your heart" has a very specific meaning here in the deep south... It translates to, "Forgive him his stupidity / brain damage / birth defects / general retardation.

Steve S

Superiorwelding · Sat Mar 07, 2015 10:56 pm

Otto Nobedder wrote:I won't argue about 98/2 being a great choice. I would not have thought of it, since I don't use it.

Jonathan, "bless your heart" has a very specific meaning here in the deep south... It translates to, "Forgive him his stupidity / brain damage / birth defects / general retardation.

Steve S

Well don't take offense from me, I meant none of the latter. Maybe the stupidity

I am just kidding.
-Jonathan

StokedOnSpokes · Sat Mar 07, 2015 11:19 pm

Thanks guys. I'll have to weigh my options, now that I have a few. Never saw that gassless SS wire before. If it actually works, it might be a good stop gap until I can get my bottle/gas needs sorted out and it's still cheaper than what the speed shop wants for running the welds.

I'll keep you posted.

exnailpounder · Sun Mar 08, 2015 8:15 am

StokedOnSpokes wrote:Thanks guys. I'll have to weigh my options, now that I have a few. Never saw that gassless SS wire before. If it actually works, it might be a good stop gap until I can get my bottle/gas needs sorted out and it's still cheaper than what the speed shop wants for running the welds.

I'll keep you posted.

Welcome to the site! I am curious at to what the Speed Shop wants to charge you for the 2 welds if you don't mind me asking. I have a buddy that wants me to de-cat the headpipe on his new Electra-Glide and I don't know what to charge. Thanks in advance!.......Jeff

Mon Mar 09, 2015 5:31 pm

exnailpounder wrote: ...I have a buddy that wants me to de-cat the headpipe on his new Electra-Glide and I don't know what to charge. Thanks in advance!.......Jeff

I always charge my buddies in quantities of beer... (Plus materials)

Steve S

exnailpounder · Mon Mar 09, 2015 6:45 pm

Beer is always good as payment but I have too many friends that forget I have bills too. I have one dumbass that didn't know welders run on electricity....he thought they run on the "gas bottle"

I often wonder how some people live so long but I guessthat God watches out for babies, drunks and idiots.

Mon Mar 09, 2015 9:04 pm

exnailpounder wrote:... God watches out for babies, drunks and idiots.

I fall in the middle category.

Steve S

exnailpounder · Tue Mar 10, 2015 8:18 am

Otto Nobedder wrote:
exnailpounder wrote:... God watches out for babies, drunks and idiots.
I fall in the middle category.

Steve S

Then you have a lot of company

jwright650 · Tue Mar 10, 2015 8:37 am

I was going to mention the self-shield SS FCAW wire, but I stopped to read the thread first...LOL(it was already suggested)
Post back when you get it welded up and let us know how things turned out.

jwright650 · Tue Mar 10, 2015 8:42 am

StokedOnSpokes wrote: I was told that the weld will contaminate the SS and there will be cracks along the new welds in no time.

Another part of the problem with this is that the SS and mild steel have two different expansion rate coefficients.One material expands with temperature at a different rate than the other which creates a lot of stress and the stress is more than the material can stand so it cracks.