welding stainless steel exhaust - Lateral-g Forums

**GregWeld** · #1 10-10-2012, 09:29 AM

Frank --

You don't mention if you're building a SEMA quality show car or a driver hot rod etc... if you're building a show car - I'd ONLY TIG weld. There's no way you're going to MIG it and have it look show quality. But if you're building a PT style driver that you're going to hammer... then MIG would be fine.

It really just makes a difference in what you're building.

frankv11 · #2 10-10-2012, 11:39 AM

Vince thanks for info !
Greg that's one of the reasons I really would like to grind as least as possible while Have it looking good. It's going to be a daily driver / show car/ autocrosser, did not start out that way but that's where it's going now.

I'm hoping to get a descent mig weld but yes tig is the way to go. Worst case I'll see if I can find some one local to finish if.

Hairline cracks that's got to suck!!!

**GregWeld** · #3 10-10-2012, 12:13 PM

Quote:

Originally Posted by frankv11

Hairline cracks that's got to suck!!!

Yes they do! And given the cost of a full custom built - food grade stainless - polished - headers to the tip system... I'm not happy about it!

But I'll just take the whole system off this winter and blast the insides and re-weld it and then polish the welds. It's like everything else on that little POS -- I've had to re do the entire car...

Cris@JCG · #4 10-10-2012, 03:35 PM

here is what SS exhaust looked like after running it @ RTTC this weekend on Blu Balz... I had to drive the car back from Irvine to LAX to drop off Karl @ the airport then drive to Oxnard.. I was deaf when I got home!

Notice that it did not break @ the welds.. I think my exhaust system is a little to stiff.. need some more rubber exhaust hangers..

**Sieg** · #5 10-10-2012, 04:28 PM

Interesting cross-over, tough to factor all the stress points with expansion/contraction and I'll assume torque twist.
Looks like some of the beads could have caused stress-risers?
Some broke behind the bead, material became brittle after welding?

badmatt · #6 10-10-2012, 05:50 PM

Looks like stress fracture. starts from no where.

Drill a hole in each end, weld it, then lap some new .065" stainless sheet over it.

Just a thought.

**GregWeld** · #7 10-10-2012, 05:57 PM

Mine is not cracked like that -- mine is tiny HAIRLINE cracks that just follow the part line (weld line) where the tubing was butted. It annoys me only in the fact that this exhaust system was several grand...

They hard mounted the system - and that was their first mistake - and I think it was that initial expansion and contraction with it being hard mounted that set up the hairline cracks... It's since been re hung allowing for some movement.

My system "grows" at least ONE INCH in length... And Tim came up with a masterful redesign of the hanger to accommodate that.

badmatt · #8 10-10-2012, 07:11 PM

Quote:

Originally Posted by GregWeld

Mine is not cracked like that -- mine is tiny HAIRLINE cracks that just follow the part line (weld line) where the tubing was butted. It annoys me only in the fact that this exhaust system was several grand...

They hard mounted the system - and that was their first mistake - and I think it was that initial expansion and contraction with it being hard mounted that set up the hairline cracks... It's since been re hung allowing for some movement.

My system "grows" at least ONE INCH in length... And Tim came up with a masterful redesign of the hanger to accommodate that.

Hmm surprised they didnt do a fusion "root" pass then a cap..

/weld inspection theory.

frankv11 · #9 10-11-2012, 07:21 AM

My system "grows" at least ONE INCH in length... And Tim came up with a masterful redesign of the hanger to accommodate that.[/QUOTE]

Hard mount cross my mind but I also noticed on my truck that it reall grows quite a bit so I'm going to be running flex line at headers and at tips . its going to be hung real close go body with high temp grommets. Hopefully that will help a bit.
See you @ sema