Airdam for the American

For some reason I decided I wanted an airdam. I'd just walked into the lab for something else, and ended up with it partially made an hour later. It took three weekends to complete (so much for instant gratification) but it came out OK, fit great, and even looks OK.

I made it entirely out of 22ga steel since thats what I had laying around, plus a 'donor' valance that was all bondo'd and bent up. Though I made it on a whim I'd actually studied the problem for some months, realizing that it's basically only simple curves in one plane (almost) and that I could probably cobble up the bends myself.

The hard part was the mounting flange which determines fit and the overall shape and dimensions. This, I chopped off the donor part. I did have to fab up the "Z" shape that fits the fenders, which was a pain, but worked out OK.

The pictures will have to do to tell the story.

I made it with minimal tools, other than a small Lincoln MIG welder. Bosch jigsaw, two hammers, 4" Wilton vise, some chunks of steel as dollies, an angle grinder. The corners were bend by hand using a 4" chunk of PVC pipe as the form. I welded too fast; metal stretched around the air ducts. I did use bondo on it, and it doesn't look that great up close, but with some care it could look pretty good. It added probably 15 lbs. to the nose of the car over the stock valance. I made my own "V" and "Z" shapes from sheet steel for internal bracing instead of tubing stock.

I drove with it for one week, hated the loss of ground clearance, took it off and fixed the original valance. It bent the fenders a bit when I bonked a driveway. Unfortunately I put brake air ducts right where I'd want to cut it raise it. I could cut right across the holes and patch with a half-moon patch, but I don't feel like it, my interest has waned.

I'm quite happy with the wheel opening however; I continued the factory curve past 180 degrees; yet there is room for jounce all around.

Glad I did it though, I got a lot of practice in with sheet metal. Maybe in the spring I'll look at it again.

Before and after.

The donor valance. Pretty badly bent up, though no real rust. I chopped the top mounting flange off it.

A serious front-end collision with this car is not recommended. There's not a lot of mass or box between the stylishly thin bumper and the driver.

Most of the sheet is flat; however I did a gentle curve to the front dam portion by stressing the steel in the center. This gave it shape and added stiffness (preventing oilcanning) then I bent a "V" with added ears as bracing.

Not shown is the tedious cut-fit-repeat needed to make it work. Wasn't too bad though. I finally learned that steel is not a solid, it's a malleable plastic (in the non-petroleum sense of that word).

Done! It's painted with Eastwood Rust Encapsulator/primer. I took the opportunity to do all the edging of the fenders and such while it was apart.

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