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rockytopper R.I.P 5-13-2017
02-16-2015, 08:13 AM
I'm installing a pypes stainless exhaust system in my nomad project. It is designed to mate with headers or small block manifolds. I'm running LS3 Camaro manifolds and need to fabricate some mandrel bent down pipes made from 304 stainless. Can I use my mig to tack the pieces together? I plan to take it to a shop that has TIG to get it welded up. I only have mig and a stick welder on hand.
Thanks
Rocky

chevynut
02-16-2015, 08:23 AM
Are you planning to use 308 MIG wire? I personally wouldn't tack it with mild steel.


http://www.lincolnelectric.com/en-us/support/welding-solutions/Pages/compact-welders.aspx

Rick_L
02-16-2015, 08:51 AM
Welding it with mild steel means it will rust there, especially on an exhaust system. If you're going to weld with that, you might as well get mild steel pipes too.

rockytopper R.I.P 5-13-2017
02-16-2015, 12:25 PM
I only want to tack it in a couple of spots so I can test fit it and then I'm paying to have it welded with a TIG. They should be able to remove my tacks with a cutoff wheel or the like.. else I will just use duct tape best I can.

Also I have read you cannot buy stainless mig wire in small quantities meaning you pay out the A.. for it or I would just go buy a small roll and weld it all myself. Cheaper just to pay a pro who already has tig.

chevynut
02-16-2015, 12:47 PM
You might get away with having the welder re-tack it with SS then grinding your tacks off.

rockytopper R.I.P 5-13-2017
02-16-2015, 02:09 PM
You might get away with having the welder re-tack it with SS then grinding your tacks off.

That was what I have in mind.

NickP
02-16-2015, 02:49 PM
How about some extra wide band clamps? Or, just go get a spool (small) of 308 wire

rockytopper R.I.P 5-13-2017
02-16-2015, 03:03 PM
How about some extra wide band clamps? Or, just go get a spool (small) of 308 wire

I see now it is available in small quantities Thanks. Will I be good to weld 409 stainless with the 308 wire? Most of the system is the cheaper 409 stainless and the down pipe I'm making is 304 stainless including the flange and o2 bung.

It looks like I need 308 & 309L wire.

rockytopper R.I.P 5-13-2017
03-08-2015, 11:30 AM
Well I wimped out, I'm using Nick's advice on using band clamps but I'm dropping them off at a pro's shop that has a Tig welder. I'll probably just get him to weld the entire system after I get it all fitted with clamps. It took me the better part of 2 days just to figure out how to fit
these down pipes. It took one 60 degree mandrel bend and (2) 15 degree bends to link the ls2 manifolds to the pre bent pypes crossover system. I am also having to fab new tail pipes. I bought what is pypes wagon exhaust assuming the pipes existed at the rear bumper corners but they exit right behind the rear wheels meaning I have to cut them and add a 2 ft extension in them. If I'd known this adhead of time I might have considered another exhaust system.
http://i282.photobucket.com/albums/kk243/rockytoppers1/Mobile%20Uploads/image_18.jpg

chevynut
03-08-2015, 01:25 PM
On my exhaust I uses some plumbing clamps and cut holes in them for the welds. They're about 2-2.5" wide and have a rubber sleeve in them...I just tossed the rubber sleeve.

rockytopper R.I.P 5-13-2017
03-08-2015, 04:10 PM
On my exhaust I uses some plumbing clamps and cut holes in them for the welds. They're about 2-2.5" wide and have a rubber sleeve in them...I just tossed the rubber sleeve.
That would work even better. I'm just glad most of the system is slip jointed except the tail pipes I have to fab. I might try your plumbing clamps on them if I can find them local.

chevynut
03-08-2015, 04:33 PM
Home Depot

http://www.homedepot.com/catalog/productImages/400/93/933f16d5-868f-4bf7-ade8-b382a63ec714_400.jpghttp://www.homedepot.com/catalog/productImages/400/ff/ff6bbf1d-17e6-4f1d-9e66-50a566155752_400.jpg