Advice for undertray panels?
 

I am looking to put up some panels under the car but I'm not quite sure what to use for materials. I'm thinking polycarbonate plastic or something light and strong. I also need a good way to fasten it to the car. I need something that I can remove when I change the oil and perform other kind of maintainence. Any suggestions?

Materials:
Coroplast
plastic paneling board stuff from Lowes/Home depot

Fasteners:
screws
nylon push rivets from Lowes
other types of trim fasteners

Do a search on coroplast and on skirts you can see what others have done.

Polycarbonate might work well but it seems a little stiff and a lot expensive. :-) It would be nice though...

I'm thinking plywood for my car, if/when I ever get under there to do it.

They make 5.5 mm. and something like 2.7 mm. Lauan plywood.
1/4 inch is just over 6 mm., so you get the idea - this stuff is thin and lightweight. About $15 and $7 per sheet, respectively.

I'm going on the theory that there's enough airflow to keep it dry. My plywood + plastic air dam was on for about 7 weeks and I saw no evidence of delamination. Ymmv of course.

Where can you buy coroplast

Best deal, after Election Day clean up some signs.
Or contact your local political parties, maybe some candidates have old signs that need removal from basements.

Signmaking shops.
I paid $30 for 4x8 feet. They cut that from something much bigger!

Also some art framing shops.
Or shop on line but you'll be shipping something pretty big.
Just google "coroplast".

I found the best price at an industrial plastic supply I found in my yellow pages. Local sign shops are very expensive.

Recycling centers and city right-of-way cleanup crews have also been suggested as sources.

wouldn't you want something stiff? I think the coroplast would be too flimsy. wouldn't it?

what about clear sheets of acrylic? I found some at Orchard Supply Hardware.
I think coroplast is lighter but is it stiff enough?

Why not aluminum sheet? It's sort of expensive, but I have some lying around from my grille blocking.