Coroplast - supporting bracing for "Aero Tail" on my trailer

[drudis]

(Read a LOT of posts about coroplast, especially the RV with the boat tail...)

How much BRACING is required to support these 4'x8'x.156" coroplast tails behind my 6'tall x 8'wide enclosed snowmobile trailer?

Should I run just a 1"x1" aluminum angle, in the two upper corners? (Indicated in RED in photo).

And 2 more angle-aluminum in the lower corner (edge) also?

Do I need more structure, as in creating a "picture frame" of the 4 corners, and tying them all together... (pictured in BLUE)?

[Fat Charlie]

There's probably going to be a lot of buffeting, and coroplast isn't as heavy duty as the ones the big rigs use. I'd go with the picture frame.

[Piotrsko]

Edge support is nice, but I believe you would be better off anchor supporting the centers since it would reduce flex and stress

[freebeard]

Do you have the Coroplast yet?

What are those stringy white things in the fourth picture?

[drudis]

Originally Posted by freebeard

Do you have the Coroplast yet?

What are those stringy white things in the fourth picture?

Have NOT purchased anything (yet).
The frame design was from the RV thread... I was thinking of just doing the 4 corners, and picture-fame (tying 4 sides together at center).
https://ecomodder.com/forum/showthre...d-e-18151.html

[freebeard]

Have NOT purchased anything (yet).

Cool. Coroplast is not fit for purpose. It's fine for mockups and experimentation, but the final material should be Polymetal or equivalent (Alumapanel, Grimco Maxmetal).

It cost more than plywood but is 1/10th the weight. The samples shown were sheared, rolled and braked by hand.

It is pre-finished and would match the build quality of your trailer.

The frame design was from the RV thread... I was thinking of just doing the 4 corners, and picture-fame (tying 4 sides together at center).

Polymetal has sufficient shear strength, you could make it a monocoque box. With Cardboard Aided Design or Coroplast, you'd want a frame that is triangulated.

http://hiataircraft.com.ua/wp-conten...14/06/fuse.jpg

[slowmover]

The forces on the tail are FAR greater than coroplast can handle.

There are about three designs of trailer tails on big trucks. Take some pics at a truckstop. Open and closed.

See the STEMCO site. That fully boxed version is great for FE. But in a heavy crosswind it’s leveraging the trailer wheels off the ground. The driver doesn’t have his trailer tandems as far back as allowed, he’s in trouble.

[gumby79]

4x8sheet $69.30usd and a little more durable final skin

8mm Twin-Wall Polycarbonate Sheet - 47.25"W x 96"L

Support required depends on pressure balance and forces involved
The one being a picture called a picture frame I see as a bird cage support structure you would either bend the colorplast over the framing or cut panels to fit between the frame sections like gussets.


Pressure balance as mentioned is critical to dealing with off angle wind or side wind. Couple of days ago driving South through Idaho in a ground blizzard even pressure balance was very important the front tires would actually slip a little as they hit the ice first giving me time to respond with the drive tires

[freebeard]

8mm Twin-Wall Polycarbonate Sheet

Better than Coroplast but it's still brittle. I have canopy/bridge between my Airstream and carport made of the stuff.

It's less flexible than Coroplast.

[gumby79]

10mm it's what I used to create the internal structure of my nose cone using a heat gun I was able to bend it into oval shape. Extremely Ridgid Id say 60lbs centered on a 3 'span perpendicular to the web=1/2" deflection , using an 8' pice for a temporary shelf

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As for spacing of support it depends on if the support is with the perpendicular web or acrossed it.