MIG Stainless to Mild Steel?

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SteveHGraham
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MIG Stainless to Mild Steel?

Post by SteveHGraham »

First off, the tool bug is biting again. I have a Lincoln PowerMIG 180C and an AlphaTIG 200-whatever, but I can't do MIG on 120V, and it has been bothering me. It would be nice to have a little MIG/stick machine I could use anywhere, without a generator or 240 line. The HF Titanium 200 multiprocess is looking really good, and they have a coupon for about 10% off. It's 24 pounds and gets raves.

Second, the bug is biting because of my garden tractor. I've been fiddling around, replacing the muffler with something I slapped together. I need to join a stainless pipe to a mild steel pipe, and a clamp is not going to work well.

Here is the question: am I going to have any problems if I MIG these together? I don't care about minor BS, like the appearance of the weld. It's an exhaust pipe. I just want to prevent it from falling off. Also, let's face it. My welds are ugly even when I use the right materials.

If I do MIG this, does it matter whether I use mild steel or stainless wire?

I guess I could man up and try to tack it with the TIG. Wouldn't be as much fun. I have some silver solder rods, but I have never used them. Don't even know if I have flux. Bought them before I moved north, and I still don't know where everything is.

The obvious question is why I would complain about the cost of a John Deere muffler and then spend $600 on a welder I arguably don't need. One big rationalization I came up with is that I would be spending money on something neat and useful instead of another bad muffler. Also, I don't know what to do about the mounts, which appear to be busted.

Oh, wait. I forgot. No one here ever tells anyone not to buy a tool. I'm safe.
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LIALLEGHENY
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Re: MIG Stainless to Mild Steel?

Post by LIALLEGHENY »

You want to use a stainless wire on the MIG as well. Just like TIG, you want the stainless to be better than the parent metal.

I'll tell you not to buy a tool if it is junk......
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SteveHGraham
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Re: MIG Stainless to Mild Steel?

Post by SteveHGraham »

Thanks for the help.
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NP317
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Re: MIG Stainless to Mild Steel?

Post by NP317 »

You might(?) need to use shield gas to work with stainless steels.
I've never tried.
RN
LIALLEGHENY
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Re: MIG Stainless to Mild Steel?

Post by LIALLEGHENY »

Correct, you want to use shield gas.

I'm sure everyone has seen the flux coated MIG wire that comes with the Lincoln welder sold at Home Depot. They advertise that you don't need gas, but have you ever tried welding with it? The wire is garbage, and if you get something that looks like a weld it was entirely by accident. There are flux coated wires on the market that work extremely well, the majority of which require shielding gas. There are a few that don't need the gas, and do work rather well, but it still advisable to use shielding gas if for no other reason than to help cool the MIG nozzle .

Nyle
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SteveHGraham
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Re: MIG Stainless to Mild Steel?

Post by SteveHGraham »

I have C25, straight argon, and a couple of little CO2 tanks I used to use for beer kegs.

I would like to try flux core wire sooner or later. I've never used it.
Every hard-fried egg began life sunny-side up.
LIALLEGHENY
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Re: MIG Stainless to Mild Steel?

Post by LIALLEGHENY »

Use C25 for the MIG
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SteveHGraham
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Re: MIG Stainless to Mild Steel?

Post by SteveHGraham »

I also have beer gas, which is CO2 and nitrogen. Very nice for dispensing stout.
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choprboy
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Re: MIG Stainless to Mild Steel?

Post by choprboy »

You want to use straight argon with stainless MIG wire, CO2 or C25 with mild steel MIG wire, DCEP. DCEN for flux cored.
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warmstrong1955
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Re: MIG Stainless to Mild Steel?

Post by warmstrong1955 »

Out of what you have, the Argon would be the best choice.
75/25 has too much CO2, and will make for a sooty black ugly weld in the stainless, even welding it to carbon steel. The carbon (CO2) basically UN-stainless'es the stainless.
Argon/ CO2, but 98/2% is more popular for stainless. Tri-mix, which is much helium is a good one, but wildly expensive. I use that on my Miller 135....as it tends to run hotter, and make a prettier bead. Glad I don't use a lot....it's about 3 times the cost of a bottle of 75/25.
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LIALLEGHENY
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Re: MIG Stainless to Mild Steel?

Post by LIALLEGHENY »

As Shultz would say"very interesting". I did some digging around on different welding sites, manufacturers site, etc, and everyone has something different to say when it comes to welding stainless to steel using MIG. Some say use argon, others say absolutely not, some say C25, others say no, TRI-mix is the one gas everyone agrees upon, and I have used it and it does work quite well. If you don't have it , try what you do have and see what works best for you. As for wire , use 309 or 312 if you have it.If you don't use 308, 316.
Better yet use your TIG since you have one.

Nyle
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SteveHGraham
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Re: MIG Stainless to Mild Steel?

Post by SteveHGraham »

I used the C25. I think.

Now I'm afraid I got in a rush and connected the argon instead. I'll bet I did. I think that would be a happy accident. I used argon when I used this wire on cast iron, and it worked perfectly.

Anyway, the pipe is attached. The welds are very ugly. I started too hot because I did not know what settings to use, so I blew through a couple of places and had to fill them in. Very small perforations, so the pipes are fine. Like it matters when you're mowing grass.

I used .025" L308, because I had it. I am not a great welding guru. I assume the settings for .030" are too hot for .025", right? Anyway, I used a .030" setting from the chart on the welder, and I made the mistake of picking the larger of the two likely looking metal thicknesses. I guess I should have started two steps down and turned the welder up if necessary. I did lay a bead on a sheet of thin steel first, and it looked fine.

The Titanium welder is very nice for the price. It's around 24 pounds and very small.

Now I want a tank for it. I think the intelligent thing is to get 40 cu. ft. of C25, because I want the welder to be portable, but I wonder if I'll regret going that small. My existing C25 tank is 80 cf. I don't weld enough to run out unless I leave the valve open when I go to bed.

I want to start practicing TIG again. I got a better pedal for my AHP. I know I should listen to people who say to learn stick first. I should probably do that, since the only time I tried to stick weld, I created a monstrosity.

I don't know if the little Titanium can be made to work with a pedal. Also, it's scratch-start, so I have to figure that out.

I think this is a neat welder for anyone who has never welded. Not much money is involved, and you can work your way through three DC processes before buying another machine.
Every hard-fried egg began life sunny-side up.
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