Hey I just talk to the head guy at the welding shop, he says to use stainless wire and the tri gas, if you don't want to buy a bottle you could rent one for a couple dollars a month.

 

Awesome. So with the trimix do I still need to backpurge? Any specific stainless wire?

 

Nice improvisation. SCH10 SS takes long enough to cut on the bandsaw, I can image there was a lot of cutting with a hacksaw.

What do you plan on doing for the 2+3 runners?

Champagne of beers eh?

 

Nice work!

How was it cutting stainless with the hack saw? I remember burning through a bunch of sawzall blades cutting stainless to build an exhaust.

 

No he said that you dont have to back purge with the mig and tri mix

 

Honestly, hacksawing was not as difficult as people make it out to be. A little bit of exercise, definitely, but not too hard. Keeping it straight is a bit of a challenge.

The number 2+3 runners will be done like Stein/18psi etc. Very simple, semi-straight into the collector. Not ideal, for sure, but I didn't order enough straight pipe or bends to make a full on 4 into 1 merge collector mani. Nor do I have the skill or tools etc.

 

Ideally you always want to backpurge stainless. If the weld penetrates 100%, the inside will "sugar" (oxidize) unless backpurged.

 

Thats what I thought. Isn't there a paste of some sort that can be used on the inside of the joints to achieve the same effect?

I'm going to go to airgas today and ask them what they think. I'm pretty sure i'm going to end up running trimix with backpurge of pure argon if I end up migging this mani. I'm really wishing I had just gone carbon for this manifold at this point.

 

Thats what I thought but he said it wont. I only Tig stainless so back purging is a must.

 

I'm going to go to airgas today and ask them what they think. I'm pretty sure i'm going to end up running trimix with backpurge of pure argon if I end up migging this mani. I'm really wishing I had just gone carbon for this manifold at this point.[/QUOTE]

well you can just weld it up with your standard mig wire and gas you have, it will work but it wont be stainless anymore, muffler shops do that all day long. you will just have a shinny mani with rusty welds

 

well you can just weld it up with your standard mig wire and gas you have, it will work but it wont be stainless anymore, muffler shops do that all day long. you will just have a shinny mani with rusty welds [/QUOTE]

Lol. I've got the stainless, I want a stainless weld bead =P

 

Solar flux is what you're thinking of. It's great for exhausts,downpipes and headers, but I wouldn't use it on a turbo manifold, unless you think you can grind it all off in between welds. The stuff will flake off and damage your turbo.

 

Wish you were closer. I have a TIG, but no expierience with stainless & back purging yet. Just got the welder over the summer. Only done mild steel and aluminum so far.

 

I never used tri mix gas. waste of money. Ive actually never even heard of it untill 18psi's build. For aluminum i love using 75/25 helium! Burns hot and leaves great bead formation (especially with pulse) with a shiny weld to boot. Argon gas with argon back purge. Bring some beer and a little bit of cash we can do it this weekend. (Let me know so i can go snag an alternate tank for purge).

BTW i have been TIG'ing for 1 year @ 60 hours a week.

 

It wont be done by this weekend. Maybe next weekend, we'll see how progress goes.

I'm not causing trouble by tacking it with regular carbon wire am I?

 

The only thing is that at the tack there will be a lower chromium content then the surrounding area. We will grind them out before welding over them.

 

Looking good man. I don't envy you cutting with a hacksaw. I spent a lot of time with my bandsaw, angle grinder and cutoff wheel in the die grinder. The cutoff wheel is your friend when hand coping joints. Much easier to handle with one hand and holding the part in the other.

 

I've got to say, I am uber impressed that you are able to make those cuts with a hacksaw too, it isn't even one of the high tension frames (which helps a lot for future reference.) I'm surprised the supplies from weirtech were so cheap for SS flanges and SS schedule 10 tube. I'll probably have to order from them, though I am still on the fence of if I want to do it in SS or mild, just because I figure I will be learning as I go, and it is cheaper and easier to learn on mild (though i've got the welding part down... go figure.) Did they sell you the exhaust flange with the bolt holes already sliced for thermal expansion?

 

Two things, the relieved bolt holes is new to me. Might be something they just started or maybe just the stainless. My wiertech mild flange wasn't cut. I have had zero problems with that since I installed it.

Also, I used stainless weld els and wiertech mild steel flanges together. Use 309L filler rod to join the two with no problems. In a year now, I have seen no rust on my flanges to speak of and the stainless to mild joints have held up fine. It's been done by many people before me. Stainless flanges are 3X times the mild steel price.

 

yes, my flanges are mild steel as well.

In retrospect, getting stainless parts at all was my biggest mistake. I'm pretty much decided on paying someone else to tig it for me which adds more to the bottom line of this project.