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Old 11-11-2014, 04:15 PM   #5 (permalink)
drrbc
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Quote:
Originally Posted by freebeard View Post
Will these four pieces be compound-curved or flat?

How can 1% of difference affect the difficulty in manufacture?

An aerocap shouldn't produce up or down force. If it does it's not optimal for forward progress. Don't count on making the sides flappy to recapture air flow.
Simple, when viewed only from the rear. The top and sides follow the curves of the cab top and rear pillar when viewed from the rear. (took a pic, blew it up in Photoshop, and matched them to some known curves). But the decreasing height front to back make it compound.

Making a curve from a flat sheet requires a bit larger area to cut curves into the sheet. It's a lot to do by hand and hard to get accurate. The Sintra can be stretched somewhat to avoid puckering but really requires a 3D mold, a large oven to evenly heat the entire piece, and more than 2 hands to form it before it can cool. I don't have any of that.

I decided on flexible joining after my first attempt with aluminum angle and channel resulted in a bent frame when tested. The idea of all flexible construction was really to avert some of the buffeting of a crosswind or semi. I was also thinking if you can decrease even a small percentage of that it may improve drivability. And the Sintra isn't really "flappy" as it is flexible- you can easily displace a step an inch to the side and it comes right back.

And I also guess there isn't much difference in going from 12 to 13%. But as Sven noted above- I overthink things.
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