I recently purchased an arc welder and got to work on a heat sheild for my aftermarket header. The header is tri-y design and eats a lot of space in the engine bay. The first model I made tended to bend because of the thermal expansion during welding, causing two of the side to become unparallel. I also bored holes throghout which could have wekend the steel. Is there a way to weld 3/32 stainless sheet metal so that it will not curve? Second model did not do so, only because I doulbed the sheet metal, and I didn't bore, but it is much heavier. Any suggestions?


This was the first model

 

Don't the holes defeat the purpose of the heat shield?

 

Tack the parts in place and do it bit by bit letting it cool down between welds. Don't put holes it in, no reason to.

 

Yes holes defeat the purose, I guess I just needed to have someone tell me that. I'll try tacking like was mentioned, thanks.

 

tack everything where u want it with no gaps, then tack every 1/8 or 1/4 inch. then when u weld it, weld each seam in the same direction. tricks to keep stainless sheet metal from twisting too bad. if ur using TIG dont use filler and try to fuse it. hense the gapless fitment

 

I am using an arc welder, which heats the metal in a broad area compared to wire welders. If I do make tacks, how big should they be? If welding two peices at an angle, should I weld the inside or outside? When I did the inside, the seam started to crack after I put it on the car.

 

Wait, your sticking it?

 

You shouldn't have to weld from the inside with thin sheet metal, a tack is just a spot the size of a small pea, just to hold the piece in place before permanent welding. If you want to weld both sides then I would start on the inside tacking and welding then do the outside, you wouldn't need to tack the outside after the inside is welded.

 

i have a few questions, first do you really need a heat shield for n/a headers that are already heat wrapped with what looks like an aftermarket radiator, dual FAL fans and a radiator diversion panel (how hot are you running?)? next, why do you have to seem weld the whole piece cant you just stitch it so it doesnt warp, or better yet since it appears to just be a 3 flat-sided piece can you just make a cardboard template and bend the metal to the shape you need on the edge of a table. you could cut one solid piece and have it bent and mounted in 20 minutes with nothing but a pair of tin snips.

and on a side note: if you have one front strut bar that is solid mounted (the top one) do you really think adding a second front strut bar that is pivot mounted (A.K.A. doesn't really do much, if anything) is gonna help you out any? especially since you were worried about engine bay room.

oh and what is the orange tube thing in the lower left corner of the pic (in front of the abs stuff)? is that blowing "cold air" onto the filter?