I got an all new exhaust system and I'm putting dual exhaust on. I'll be fabbing some of it while installed on the car, specifically while on jack stands and over my head. I've never worked on something like that and I'm curious about any safety precautions. I don't think there is anything besides the obvious watch for anything that may drip down, but are there any other things to watch out for?

 

since you're welding exhaust you won't have to worry about anything inside the car as the floor pans won't get hot enough. just tack everything up, unbult it, then run full welds. don't try and run a bead while you're working over your head or your just asking for a puddle of molten metal in your face.

 

Always clamp as close to where you're working as possible. You never want to get the ECM in the circuit, ESPECIALLY if you're using a TIG

 

As an added precaution, be sure to unhook your battery, so you don't get a surge and fry your CPU. If you can tack it together and get it back out in one piece, then by all means, weld it that way, but if you can't, brazing or soldering would be a whole lot easier.

I don't know what material your exhaust is made out of, but even if it was high quality stainless, you could heat the pipe and just drip some silver solder on the top of the pipe and it would run down nicely.

If you have to weld it together while on the car, make sure you wear leather if you can, and even if you don't, be sure you have no frays on your jeans or other clothing, or you could catch a spark.

Welding out of position can be tricky, are you using a MIG?

Mathius

 

Consensus on the welding forums is that you’re better off with the battery connected. In most cases you’re only using about 20VDC to weld and the battery actually adds a small bit of added protection…

Tack, remove and run the bead is what I usually do.

Silver solder will not work anyplace prior or around the cat. Braze might, but to use either you’d need spotless joints with real lap joints.

As far as protection… I know more then one person that has hearing damage from laying under a car with a welder and having one of those super hot goobers roll into their ear. I’ve never bothered myself, but most of them wear some sort of hearing protection now when welding in that position, not to protect them from noise but hot sparks. I’ve had a set of shorts catch fire while welding LCA brackets under the car… Be careful and keep a fire extinguisher handy.

 

You need a full hood as well as a skull cap and good welding gloves. As suggested before, wear a leather welding jacket if you can. Also consider wearing safety glasses too. This will prevent any "bounce back"...not a pleasant experiance. My personal experiance is to never weld on a vehicle with the battery connected....but to each his own.

 

Depends on if he's running the stock cast iron manifolds or what, but I just figured if he's welding at all, it's gonna be aluminum, stainless, or steel.

Excellent point about sparks in your ear. For about $10 you can get one of those welding caps. They look like engineer hats or something similar. They're goofy looking, and sometimes uncomfortable, but one good thing about them is the soft brim can be pulled down over your ear to keep sparks out (wearing the cap sideways). That's one of the things they thought me in my welding classes. When I'm welding horizontal or vertical, I'd rather wear a skullcap, but for overhead the cap is gonna offer more protection.

Mathius

 

Wow, good idea, I'll just tack it then weld when its off of the car. Its going to be ALOT less of a hassle. Thanks guys.