Best Material to weld a turbo manifold out of with a mig welder?

[thedean]

As the title states what is the best Material to weld a turbo manifold out of with a mig welder?

 

[boostinRWD]

Welding cast you need high nickel rod,,,or in your case
if possible nickel wire.
There are a couple special techniques to welding cast.
Might have to do some reasearch,I'm not a certified welder.

 

[Bo0sTdTsI]

By what ive seen and tried a few times preheating it to the correct temperature before welding is a must, alo need a way to control when it cools down, cant have it cool too fast. I might be off from what i do at work but its gotten the job done, pretty sure someone else can chime in with more knowledge than me im still learning in the field myself.

 

[silvreclips]

is the OP talking about repairing a manifold or building one from scratch?

 

[Bo0sTdTsI]

Woops my bad on the misread, but mild steel or stainless is fine in my opinion.

 

[boostinRWD]

Ahhh yea I miss read too.
If your using a mig welder,,I would say mild steel.
Seems a tig welder is prefered for stainless steel.

 

[Boost25]

Mild steel is the best idea for mig.

 

[thedean]

Thanks for the help guys! I would be building a manifold from scratch. From my research mild steel seems to be the best choice.

I would like to get a TIG, but that's a little out of my price range at the moment. Why do guys with TIG's use stainless? Isn't it more prone to cracking, you have to purge-weld it correct?

What Stainless Grade is the best?

 

[Cdc1221]

If youre building a mani from scratch its usually best to use stainless, and you can buy stainless wire for a mig using shield. Not sure if they offer a stainless flux type wire

 

[thedean]

If youre building a mani from scratch its usually best to use stainless, and you can buy stainless wire for a mig using shield. Not sure if they offer a stainless flux type wire

Isn't stainless more prone to cracking though? I thought a nice mild-steel mig'd turbo mani was usually considered more resilient?

 

[95TSIDsH]

mild steel will rust over time and crack stainless is your best choice look at the big names all use stainless

 

[turboglenn]

Use stainless and get the proper tri-mix gas and stainless wire for the MIG and it will be ok.. Stianless only cracks becayuse it's harder than mild but also more brittle (best to brace heavily or heat treat/aneal the entire assembly afterwards)
312 stainless is what i'm gonna say is the best for longetivity and use 316 SS wire/rod

as for those wondering abotu repairing cast...few simple steps, i'm going to assume there's a crack as that's the most common

First... find the VERY ENDS of the crack with a magnaflux job (if you don't find the real ends, you're only gonna be chasing the crack forever)

Then drill out the ends of teh crack all the way through with a 1/8th" drill bit

heat the manifold to a minimum of 350 (475 max) temperature (easiest and best to do in a charcoal grill fo rthe home enthusiast)

Then weld the entire crack before the things get too cold (don't drop below 350, maybe 325* F)

toss the manifold back in the charcoal grill, but in the coals this time, and leave it there untill the coals are cool

you can also bury a manifold in sand if you don't have a grill to use, this will hold heat in and let it cool slowly...

The OTHER WAY and this does work is to weld the cast "cold" and this is by doing things damn near the same but only welding 1/4 inch at a time then letting it cool completely (this takes longer) and more than 1/4 or so at a time and you'll get cracking again...

The proper rod to use is HI-99 or nickel-99 which is as it sounds 99% nickel, it's nice and machinable and usually only found locally for stickk welding (which is gra for welding manifolds too if you like it and are good at stick) personally i beat the flux off 99nickel stick rods and use them with the TIG (but i'm sure there's hi99 welding wire for a MIG out there too if you look online, doubt you'll ever find it locally)

but, contrary to most beliefs, the ecliupse manifold isn't cast iron it's cast steel that's how bushur and them got away with welding external gate flanges on them so long ago for so cheap... much easier stuff to work with and much more forgiving..

the holes and the crack ends goes for ANYTHING cast, just more so in iron

 

[tkelly27]

I've had home made mild steel manifolds last as long as some $$ SS manifolds. Little rust on thick steel never hurt anything. For your first manifold there is no reasom to choose anything other than sch 40 1 1/4" mild steel pipe fittings. Elbows, U's and straight pieces.

Pros; easy to cut, easy to shape, easy to weld, cheap to weld, cheap to buy, flows the same, easy to find mild steel flanges.

Cons;Will get unsigtly surface rust, sch 40 mild steel is heavier than sch 10 ss that most manifold makers use.

Welding SS you have to be careful with sheilding gas amd.heat input or you can create a brittle weld or cook the alloy right out of it. It is difficult to cut/fabricate with, and it is not cheap if you make a mistake.

I've made 4 of mild steel and they'veall seen street duty since 2009. I used 1 1/2" back then and that is too big. SCH 40 pipes have weird sizing so 1 1/2" is much larger than 1.5" ID

As you develop your skills consider other materials. Mild works so well for me that I don t even consider stainless as an option due to cost and difficulty of manufacture.

 

[turboglenn]

I've had home made mild steel manifolds last as long as some $$ SS manifolds. Little rust on thick steel never hurt anything. For your first manifold there is no reasom to choose anything other than sch 40 1 1/4" mild steel pipe fittings. Elbows, U's and straight pieces.

Pros; easy to cut, easy to shape, easy to weld, cheap to weld, cheap to buy, flows the same, easy to find mild steel flanges.

Cons;Will get unsigtly surface rust, sch 40 mild steel is heavier than sch 10 ss that most manifold makers use.

Welding SS you have to be careful with sheilding gas amd.heat input or you can create a brittle weld or cook the alloy right out of it. It is difficult to cut/fabricate with, and it is not cheap if you make a mistake.

I've made 4 of mild steel and they'veall seen street duty since 2009. I used 1 1/2" back then and that is too big. SCH 40 pipes have weird sizing so 1 1/2" is much larger than 1.5" ID

As you develop your skills consider other materials. Mild works so well for me that I don t even consider stainless as an option due to cost and difficulty of manufacture.

great point...SS done wrong is way less reliable than mild done mostly right

very true, SS is something you don't want to hone your skills as a basic fab guy on for sure as it gets pricey fasif you mess up or don't have the needed equipment already bought. Personally i have tried to specialize in stainless, 4130/4140 and aluminum work to set me apart from thebasic welding shop and keep the droves of broken rusted lawn mowers from being my main workload (and it's worked) so i can say it was worth the money i spent to cut my teeth, make my mistakes and correct them, but at the time i was making enough money i didn't really feel an effect on my busget like i would today being on a disabled SS income (god i feel fawking like i should be 70 years old saying that, but the lord has dealt the cars and i'm just playing mny hand is the only wau i can take it)

anyway, personally i would only use SCH 40 either way and take the weight over the worry that my turbo will be hangin by the down pipe and o2 wiring half way across the USA on a 1000+ ile road trip, (but that's alsop why eventhough i can build them in SS, i still have a cast manifold to rely on for DD duties) damnit my freaking hands won't do what i wantthem to time for pills, injections and waiting them to kick in, be backt o dinish later

 

[NWHTanK]

Much needed info! Thanks

 

[Wildside22]

I prefer to sand cool my cast parts when I weld them too.