What type of metal is the exhaust?

[Matthew Jeschke]

I am curious what type of metal is the exhaust on my truck (2001 chevy tahoe)? I assumed it's stainless... but what grade? I need to know what welding wire will work with it.

I welded my exhaust a few times broke every time. My neighbor sold me a once used welder, helmet, gloves, etc. It's the cheapo from harbor freight HERE. He just needed it for a small job then sold it to me for $75. Figured it would be fun to learn with if nothing else. He came over and helped me weld my exhaust after my welds broke a couple times. He thought his weld would hold but it broke as well.

I'm starting to wonder if we have the wrong welding wire. I don't know what the wire is I currently have but it's a copper color spool from Harbor Freight. Looks like this HERE the label is long gone on the spool so I cannot identify it.

 

[swathdiver]

Stainless with aluminized stainless muffler and tailpipe so says the 2002 Suburban brochure. Don't know which type but I reckon it's 304 or close to it.

 

[Matthew Jeschke]

Awesome thanks! Do you know much about welding? I'm not sure what welding wire would work with that.

 

[Just Fishing]

Flux i assume?
Otherwise you need 100% argon.


Flux
https://www.amazon.com/YESWELDER-Stainless-E308LFC-030-Diameter-2-Pound/dp/B09YT2VBYG
Read reviews, you might need a different diameter maybe? IDNK.

 

[PPV_2018]

Most muffler shops use copper coated mild steel wire (aka, ER70S-2 or ER70S-6, as pictured in your link) via MIG with ARG/Co2 Mix when doing exhausts. Some muffler shops use RG45 or RG60 (non-copper coated) mild steel rods with an oxy/fuel torch if they can get away with it. Never heard of someone using stainless wire or rods on an exhaust.

 

[Matthew Jeschke]

Gotchya, I really have no clue when it comes to welding. I had an exhaust shop weld on a o2 bung for my wideband. Their bead really melted the bung and exhaust pipe together well. It flowed together nicely. I'm probably using the wrong words all over the place but hopefully makes since what I say.

I work my welder a bit then pause (I was told isn't powerful enough to do a continuous weld). Probably say 15 seconds of welding then 15 second pause. However, the parts I'm mating never seem to meld together so to speak. It kind of sort of tacks the surface together with lots of for chicken poop (won't let me use other word) all over the place. It doesn't really get the two pieces to fully melt together... I got idea to try and burn completely through a piece of test exhaust pipe and it wouldn't burn through on full power.

Is my welder just that garbage? Talked with several other people who weld and they said it should handle the job regardless. IDK?

I really have no clue.

 

[strutaeng]

Yeah, not sure what muffler shops but probably not actually stainless steel filler wire because their welds do rust...which is not big deal TBH.

Now, I will say is that chintzy welder is garbage. That welder is just a simple transformer and it lists it as AC power source. Flux cored (and GMAW or "mig") are both DC welding processes. Wrong welder. I don't even know why they sell that thing. SMH.

You can get a little inverter welder that actually works well. I bought a little Century brand 120V for little misc. jobs around the house so I don't have to drag my 240V mig/flux cored large welder around. I've never welded exhaust though...but I would recommend mig for exhaust. Flux core is meant for thicker metals.

 

[PPV_2018]

Gotchya, I really have no clue when it comes to welding. I had an exhaust shop weld on a o2 bung for my wideband. Their bead really melted the bung and exhaust pipe together well. It flowed together nicely. I'm probably using the wrong words all over the place but hopefully makes since what I say.

I work my welder a bit then pause (I was told isn't powerful enough to do a continuous weld). Probably say 15 seconds of welding then 15 second pause. However, the parts I'm mating never seem to meld together so to speak. It kind of sort of tacks the surface together with lots of for chicken poop (won't let me use other word) all over the place. It doesn't really get the two pieces to fully melt together... I got idea to try and burn completely through a piece of test exhaust pipe and it wouldn't burn through on full power.

Is my welder just that garbage? Talked with several other people who weld and they said it should handle the job regardless. IDK?

I really have no clue.

laying a couple of beads down and stopping is pretty common tbh. A “continuous” weld you are not going to achieve with virtually any welding machine, most welding machines usually don’t have 100% duty cycle unless it’s a $35,000+ diesel powered welder/generator. So that’s not your issue.

No offense, but it may be more of a pilot not the plane type of deal if you’re burning through and getting spatter and popping. You probably have your amps turned up too high relative to the metal thickness you’re working with. There’s also a possibility of the wrong wire and equipment being used as well and to add to that:

Now, I will say is that chintzy welder is garbage. That welder is just a simple transformer and it lists it as AC power source. Flux cored (and GMAW or "mig") are both DC welding processes.

^THIS.

Harbor freight welders are complete crap. Can you weld with them, sure.. but it’s not going to provide the most desireable results.. usually. Also, personally, i do not like flux cored welding. It has its advantages, but really the main advantage is probably being able to use it in windy conditions. IMO nothing protects the weld pool the way shielding gases do. Also, FWIW, A/C can be used with GMAW for certain applications.

My suggestion to OP is play around laying beads on scrap metals that are a similar thickness to exhaust pipes, that way you can figure out what wire speed and voltage you need to be at.

i promise you muffler shops are not using stainless welding filler unless it’s the bosses custom restomod ‘49 ford or ‘57 Chevy or something.. they are using ER70S-6 wire with argon/co2 gas.

 

[strutaeng]

Flux core welding (FCAW) has a bad rap with automotive guys, but there's nothing wrong with it, actually.

In fact, it's WIDELY used and industry standard in structural steel fabrication. Think big 1 1/2" thick base plates welded to heavy columns or plate girders. FCAW has excellent deposition rates and ***********. There's actually two types of flux core welding FCAW-G and FCAW-S. The G still requires shielding gas, but has greater deposition rates. Ideal for high production in fabrication shop use. The self-shielding or S is better for field welding where you may get a cross wind.

That's not here nor there.

Edit: p-en-etration got censored out! *********** WTF! LMAO

 

[Matthew Jeschke]

Certainly it's the pilot lol I SUCK. That said my neighbor with a lifetime of experience couldn't made a weld that held with that machine on my exhaust either. His welds didn't look too different from mine. It's hard for me to explain, the materials never melts together?

I also was trying to get it to burn through something as I couldn't figure out why the materials wouldn't melt / it wouldn't lay a bead or puddle. I just got mostly surface stuff like chicken $h1t. I couldn't get it to melt through anything in my test attempts let alone on the parts I was trying to weld on either the high or the low setting (it only has two power options).

I'll look at an inverter welder. Is it this one HERE ? Guy at parts store said he had a chepo Lincoln welder he felt was similar to mine. He really thought mine should cut the mustard but the Lincoln base model must be far superior?

I have a 220v plug in my garage as well, is there a reasonable 220v wire feed welder? I'm not sure I can afford / want to get into the gas stuff yet. It's nice and I fiddled with it years ago but bit more than I want for my little jobs.

Thanks for the tip!