Join Date: Jan 2007
Location: Southern Ca
Car: 00 OB 07 OBXT
Feedback Score: 0 reviews
No it's not dangerous [for the car] to weld on an exhaust system, they do it all the time.
Sure it's worth $40 to have someone do it, most people don't have the equipment or skill to weld. I have the equipment but my skill is somewhat rusty since i don't do it very often. Something like this where nice looking welds aren't an issue, I'd do.
Problem with welding stiff like this is the different thickness and alloys of the metal. Usually when you try to weld something like this, the thinner metal gets way too hot and burns through or weakens the metal around the weld site. Then you have the constant heating and cooling and eventually it lets go.
If you can have a friend do it for a six pack or a cheeseburger, that's the way to roll, if as you say he has a decent idea of what he's doing.
To get a decent weld on it, make sure the weld site is clean of rust and grease.
Only other thing i can think of is to shoot some self tapping screws through the shield into the exhaust pipe. the threads should seal well enough where exhaust leaking isn't an issue.