Construction of boat tail, wheel skirts etc. out of PVC and Coroplast

[KillerGardevoir]

I just had this idea and after searching the site found alot of people doing something with PVC skeletons and coroplast inbetweens(technical term i don't know it) but was wondering if anyone had a definitive way of doing this effectively because (after I buy a new car, current one has some sort of acceleration gas mileage trouble) I want to start modding my car but doing it cheaply and not bankrupt me (high school student).

Also i'd like to know if anyone knows a place that sells coroplast in northern Idaho, eastern Washington area because I know of very few places that could have it (close to none)

[Bicycle Bob]

Are you talking about Coroplast panels on a PVC pipe frame?

Coroplast is available at large building supply stores, sign shops, and roadsides.

[theunchosen]

Depending on the car. . .coroplast can be drilled directly into plastic bumpers, side skirts and rear bumpers. Some supports can be useful but most of the time not neccessary.

[KillerGardevoir]

What do you mean by 'drilled in'

[theunchosen]

Well depending on what the udnerside of your car looks like you might be able to use self-tapping screws and just drill the coropast into the plastic side skirts and front and rear bumper.

If self-tapping screws don't work then you need a partner to hold it in place after you drill a short hole and then switch heads and thread a screw into it partially. The poly plastic that most cars use for side skirts and bumpers readily accepts metal screws.

As far as doing a full belly pan I would put screws no further apart than every 6 inches to hold it in place. Washers would be adviseable in the event the pan shifts and gauges itself you don't want the screw heads ripping through. I would make them more common on the front front bumper because letting air get up and between the bumper and the coro there might cause premature wear.

right now I have some poly plastic screwed in as additional protection for the oil pan(My car is very low). It alerts me a moment before I scrape so I might have enough time to change my angle of attack on speed bumps to resolve the issue.

If you have to use a drill and don't use a tapping bit make sure you don't use a drill bit thats too large or the screws will be worthless. A guide hole ought to be enough, just something so the tip of the screw doesn't have to do anything and the threads can get purchase.

[brucey]

Woodscrews go right through the plastic on the bumpers easily and barely leave a mark. They hold well too, espaically with a washer.

[aerohead]

If the boat tail is enclosed and air tight,it will be at atmospheric pressure inside,and will have to contend with lower pressures "outside" which can cause it to burst if not reinforced against this pressure load.Make sure the skeleton is robust and that the center-to-center span is close enough together in areas where the bias of the coroplast offers little strength.

[Bicycle Bob]

That should be easy to avoid, with a small hole at the back, and none at the front. If in doubt, watch the panels as you increase speed.