Stick weld exhaust pipe?

[bad_idea]

I am planning on putting a 3" stainless exhaust on my 02 Camaro and I want to weld it all. I have a mig I use 75% Argon/25% CO2 for mild steel, but don't want to buy a tank just to weld stainless. I don't have a tig welder.

 

[sfckiddo]

so whats your question?

 

[12husky]

You can use ESAB 710X dual shield wire in your MIG with 75/25 for stainless. It is great for heavy work but I have never tried it on something as thin as exhaust pipe.


MCOC

 

[Justanoldguy]

so whats your question?

I thought the heading actually covered that very clearly

 

[mechan]

You can use ESAB 710X dual shield wire in your MIG with 75/25 for stainless. It is great for heavy work but I have never tried it on something as thin as exhaust pipe.


MCOC

Why would he want to use a mild steel wire for welding stainless?

 

[MRFORDMAN1994]

If you are ready to practice a lot and blow more than a few holes through it you'll be able to make the pipe solid but don't expect it to look good. I had to do a field repair on my BILs jeep Cherokee with a stick welder and couldn't get the current set just right always too hot or cold.

 

[mechan]

I am planning on putting a 3" stainless exhaust on my 02 Camaro and I want to weld it all. I have a mig I use 75% Argon/25% CO2 for mild steel, but don't want to buy a tank just to weld stainless. I don't have a tig welder.

What grade stainless will your exhaust be made out of?

(You can use a 75/25 mix on the majority of 300 series and duplex stainless. (e.g. 2205))

 

[PugetDude]

Stick weld exhaust pipe?

I have a mig....

Are you asking if you can stick weld or use your mig?

 

[12husky]

Why would he want to use a mild steel wire for welding stainless?

Looked at the wrong box. Shield-Bright 308L


MCOC

 

[mechan]

Looked at the wrong box. Shield-Bright 308L


MCOC

Would depend on what grade he is making his exhaust out of ...

If he is using a 400 series he will also need a different tank of gas ...

BUT to answer the topic question, unless one is fairly proficient with stainless stick welding you are going to be ******* in the wind.

 

[RedneckWelder]

While thin materials can be stick welded with skill and small enough diameter electrodes it's not an easy task at all.

 

[A_Pmech]

You can weld the 409? stainless exhaust pipe with steel wire, but obviously the welds will no longer have the properties of stainless. That's borderline Camaro abuse.

 

[Bobhdus]

Stick welding stainless "tubing" isn't easy. If your intent on doing it, use standard 308 small diameter welding electrode and use a stainless backer tube as a consumable to help prevent edge melt or burn through unless your overlapping the joints. The inside backer sleeve just needs to be wide enough maybe 1/2-3/4 " to bridge any gaps or edge melt. Just my opinion. The picture is an idea how it will probably look no matter what you do...

 

[mechan]

You can weld the 409? stainless exhaust pipe with steel wire, but obviously the welds will no longer have the properties of stainless. That's borderline Camaro abuse.

When in doubt 309 it!!

 

[mechan]

Stick welding stainless "tubing" isn't easy. If your intent on doing it, use standard 308 small diameter welding electrode and use a stainless backer tube as a consumable to help prevent edge melt or burn through unless your overlapping the joints. The inside backer sleeve just needs to be wide enough maybe 1/2-3/4 " to bridge any gaps or edge melt. Just my opinion. The picture is an idea how it will probably look no matter what you do...

One can't really recommend using 308 unless they know they grade of stainless he will be using ...

Stainless stick in and of its self isn't really super easy. Flat fillets aren't too bad, but when you get to verticals or over heads it is just all kinds of great fun. That would be the issue of welding the exhaust in place is you will have a constant changing position while in fairly limited space. Not to mention as you said the issue of melt through even with the lapped joints.

 

[Bobhdus]

I mentioned 308 as thats the tubing and piping I have welded. His local weld supplier will most likely have a Stainless compatible rod. The fancy rods used for various dissimilar materials are a little pricey but are usually better at lower voltages and can run kinda "gummy". Tubing/ pipe presents different challenges to weld than flat stuff but this is not a pressure vessel so as long as your not worried about cosmetic go for it. Someone posted a pipe welding techniques pdf book somewhere on GJ. It covers welding SS tubing. Best welding book I ever read...

 

[Justanoldguy]

Stick weld exhaust pipe?


Are you asking if you can stick weld or use your mig?

I thought the heading was perfectly clear.
He already explained why he DOESN'T want to mig it.

 

[Jack Olsen]

He doesn't want to MIG it because he doesn't want to buy a new bottle, right?

I would use 309 and the regular 75/25. But my SS welds would no doubt make that dog cry.

 

[mechan]

I thought the heading was perfectly clear.
He already explained why he DOESN'T want to mig it.

Because he doesn't want to buy another tank of gas, but unless he is going to be welding a 400 series stainless then his 75/25 mix would be fine. So as long as he sticks with a 300 series or duplex then he can weld to his hearts desire with the smallest spool of stainless wire his mig will take.

 

[Tinner]

The 75/25 will be fine for 300 series. The arc will be a little harsh, but it actually makes a pretty nice weld. More than sufficient for exhaust pipe. Take your time and set up the welder real good on some scrap tube. Split a piece of tube to put inside as a consumable and you'll have it made in the shade. You can even leave the joint open a tad to make it easier to see.

 

[bad_idea]

OP here,

Sorry if I was unclear on my plans, but then again, my plans are currently unclear to me too. I didn't realize I can mig weld stainless w/ 75/25. I have the y pipe in the car now, and want to weld that solid because it is moving around a bit, not sure the grade of stainless it is. I need to buy the pipe from the y back, so I can buy a 300 series stainless for that. What wire do I need to buy? What is the difference between 300 and 400 series stainless? What is the issue w/ welding 400 series w/ the wire for 300 series?

 

[welder4956]

409 stainless is the only 400 series I have seen used on exhaust. I don't see where 75/25 would not be acceptable for that ferritic grade of stainless. ER308L or ER309 wire would work fine for welding 300 series stainless to 409, and for welding 304 to 304. If you are upgrading to a higher temp grade of stainless, such as 321 or 347, you need to use ER347 wire. That will work for welding to the 409 also.

 

[Tinner]

I'll try to keep this simple. If you're welding to a factory Y pipe, it's probably a ferritic 400 series, a magnet will stick to it. It's also probably aluminum coated, you'll need to sand that off where you weld. If a magnet doesn't stick, it's 300.

309 is generally accepted as the alloy to use for welding unknown or dissimilar stainless. Also used for carbon steel to stainless. I'd go with that.

Stainless metallurgy can get complicated, here are a couple links explaining the basics in simple terms.

http://www.aksteel.com/pdf/markets_products/stainless/stainless_steel_comparator.pdf

http://www.weldingtipsandtricks.com/welding-metallurgy-2.html

Exhaust shops commonly run 309 wire with 75/25 or 80/20 gas. Some even run the 309 on mild steel. It's a simple solution that works for guys that aren't professional welders.

 

[bad_idea]

That sounds great. I don't wanna drop a bunch of money on welding this up. At the same time, I also don't want to fight with stick welding either. Thanks guys.

 

[dogdog]

....if you are doing MIG and stainless steel, I think the proper gas is the trimix ones not the standard 80/20 75/25 carbon dioxide/ argon mix even though it would work. But then again, I did flux core weld a portion of my stainless exhaust in a pinch, when I ran out of argon during tig. They are all held up fine, so far 3 yrs. The fluxcore weld portion definitely showed sign of rust developing but not yet corroded.
You are also suppose to either back purge or back shield with something on the other side of the weld to prevent sugaring or the stainless to lose it's corrosion resistances. I used Solar Flux for that, since welding gas is more expensive for me.


http://www.millerwelds.com/resources/communities/mboard/showthread.php?3538-Tri-mix-gas-for-stainless-steel-MIG-welding

 

[zkling]

I'd suggest you either run the proper setup or pay someone that has the right setup to weld it for you. Otherwise the longevity of your exhaust will be compromised. Seen it many times, had to repair it. You can always tell when someone has half a$$ed a stainless weld, especially if it is exposed to the elements as it will be rusted at the joints.

 

[jethro29]

YOU can weld it with what you have,i do it a lot.but you just won't have a stainless weld,meaning the weld will rust.but other than that,it will be a perfectly fine and strong weld as long as you are proffecient with your mig.

 

[mechan]

....if you are doing MIG and stainless steel, I think the proper gas is the trimix ones not the standard 80/20 75/25 carbon dioxide/ argon mix even though it would work. But then again, I did flux core weld a portion of my stainless exhaust in a pinch, when I ran out of argon during tig. They are all held up fine, so far 3 yrs. The fluxcore weld portion definitely showed sign of rust developing but not yet corroded.
You are also suppose to either back purge or back shield with something on the other side of the weld to prevent sugaring or the stainless to lose it's corrosion resistances. I used Solar Flux for that, since welding gas is more expensive for me.


http://www.millerwelds.com/resources/communities/mboard/showthread.php?3538-Tri-mix-gas-for-stainless-steel-MIG-welding

75/25 does result in some loss of corrosion resistance due to the increased CO levels, but would be a better option than trying stick weld it I think. That being said unless he plans on being 100% void of steel tools or carbon contaminated tooling during the build process he will end up with some amount of corrosion from that unless he is going to pickle the exhaust post fabrication.

Tri-mix or 98/2 is the better option for stainless if one is going to purchase a bottle. For thin wall tubing I would probably not want to use tri-mix probably though as the helium content makes for a hotter weld. The 98/2 would be a colder weld which would result in less chance of the base metal dropping out on him, while staying under the CO / O2 content requirements for stainless applications.

 

[e30bradley]

just use mild steel for your exhaust..

 

[bad_idea]

I would use mild steel for the exhaust, but I bought the headers and catted y pipe cheap. They are both stainless. I am not worried about corrosion prevention but so much. I am in Virginia, rust isn't as big of an issue here.

 

[Bobhdus]

I looked at borla exhaust website and all the stuff I looked at was 300 series. Btw, when you ask a weld question, your going to get a lot of expert and professional opinions. Don't be offended. You can use mild steel on stainless, just like you can use mild steel wire on cast iron. Its not the correct way to a trained welder (in my shop you could get fired), or if you have the finances and equipment to do it right but if you have to improvise these methods will work...

 

[dogdog]

don't think you needed x-ray quality welds on a car exhaust unless you are doing a show car.