How would You Do this?
 

I'm building a reverse trike and I want to build a body that is similar in shape to the vehicle pictured below. The body will have to be fiberglass due to weight concerns, so my question is how would you go about getting the complex curvature on the body? I want the fiberglass sandwich to be as thin as possible to cut down on frontal area so using the 2inch pink foam is out of the question because the added frontal area would be too much. Ideally I would like the panel to be no more than 1/2 inch thick and I plan on making them able to be bolted on and off the steel frame for service reasons.

Any ideas would be appreciated :thumbup:

http://indycycle.net/IndyCycle/091299c.jpg

Check out what the guys from the "Trucks" show on Powerblock TV did for the custom front bumper they made for their ranger (rolling thunder) project. They used a 1/4" steel rod to make a frame with all of the shapes that they wanted, then stretched fleece fabric over the frame and solidified with fiberglass resin. They left it at that, but seemed quite flimsy, although you could add fiberglass mat to that smooth fleece shape to get your strength without going too thick.

The problem I's that I'm trying to keep the weight down so using wood or steel backing material would add too much weight. I'm looking for a thin flexible material that will hold it's own shape and can be fiber glassed over.

GOOGLE: 'Duramold' and 'Mosquito' fighter.

THIN plywood can be bent into just about any shape using STEAM and PRESSURE.

try using thin lauan plywood 1/8 in thick in several layers (3) 1st layer flex to desired shape ,apply glue 2nd layer is applied then the 3rd glued when the glue cures the lamination will hold the shape its cheep, lite weight and can be fiberglassed should come out about 1/2 in thick. good luck

I guess I'll have to take a trip up to Home Depot to check out what they have that I might be able to use.

Fabric and dope. It cures rigid enough to cover a Hurricane fighter, it'll be fine for your skate. Use that for the flanks to keep weight down, sonething you can bend or form for the curved bits.

Do a YouTube search for Dick Kincheloe's Raptor, or his website Texas Raptor*|*

Basically, he cut the curve out of plywood, and curved foam into it, IIRC. Fiberglass the inside, remove the plywood supports, 'glass the other side.

https://lh6.googleusercontent.com/-k...0/DSC_4075.JPG
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https://lh4.googleusercontent.com/-M...0/DSC_4093.JPG
https://lh5.googleusercontent.com/-G...0/DSC_4782.JPG
https://lh4.googleusercontent.com/-F...0/DSC_4784.JPG
https://lh4.googleusercontent.com/-r...0/DSC_4797.JPG
https://lh5.googleusercontent.com/-X...0/DSC_4833.JPG
https://lh6.googleusercontent.com/-B...0/DSC_4873.JPG

I have seen that Raptor before but completely forgot about his methods. Thanks for reminding me! that's probably the route I will take.

Anybody have any idea what kind of foam would work for this? I'll use the pink foamular insulation for the straight vertical parts, but idk what to use for the curves

I've a HUGE admirer of his vehicle, and I'd give someone else's left jelly bean to own one.

Have you considered the wood frame, with thin plywood curved over? Fiberglass it, remove the fiberglass, flip it over, and build up the underside? Who cares what it looks like inside.

To get it smooth as glass like Dick did, you'll need to spend days sanding, filling, sanding, filling... If you're not going for museum-quality finish, I'd say just get 'er done for your first build and refine it on your second. My plan was to build a single-seater for in-town commuting, then on the second build make it tandem and focus on highway MPG.

Lots of info out there on using wood veneer: compound curved plywood

I just spent an hour trying to find a picture of a revere trike built in Czechoslovakia that used a sailplane canopy for the top. My .jpgs are in disarray. :(

Anyway, I showed this to aerohead in another thread and he sounded very knowledgeable about the *concrete* forms needed.
http://i.imgur.com/vCA29.jpg
The Hughes Sportster

hey I have an idea. now that you have pictured that row boat. how about using a kayak as the starting platform (rotational molded) old ones are cheep, aerodynamic and from 9-15ft long

aluminum?
 

From Ohio it wouldn't be that far to Oshkosh,Wisconsin and the Experimental Aircraft Association's big annual AirVenture ,each summer.
They conduct free clinics which include English-wheeling and planishing of annealed aluminum sheet.
It would be another way to achieve very thin-walled skin for the trike.

This guy makes moulding w/ fiberglass look really easy...
http://www.youtube.com/watch?v=GXzR1...feature=g-hist

Whatever you do this time around, you can always hack on it and go crazy w/ body filler to produce your next rev and make it really light and smooth. :D

Google Dick Kincheloe Raptor. I got to take a ride in it last year; he did a beautiful job on the body, etc. Lots of fiberglass with carbon fiber wings and joint strengthening. There is probably a link to contact him somewhere and I believe he has a web site up. He seemed very amiable to sharing info on his methods, etc. He had built aircraft previously with similar materials and methods.

Eighteen kilograms, that is forty pounds or less!

How much would it weigh with coroplast? :D

Fuselage
 

Look into Airplane building techniques for fuselages they combine the same principles and shapes you are looking for. They have D.I.Y. Airplane plans online you could maybe look and get some ideas for material or shapes

HydroJim, have you made any further plans or decisions or thoughts on this subject?

You could also do a "deep dish full belly pan", similar in design to those snow floormats for trucks with the 2" walls. Completely enclose the bottom, with a 4-6" lip around the vehicle, then you can jack it up under the vehicle to secure it. Put your "top body" overlapping the bottom lip so rain slides over. Smooth as a baby's bum.

If I were you I would make the mold out of foam. Make a scale model first so you can learn without spending too much $$. Measure twice cut once.

looks like a upside down kayak. probblem solved and it would be thermoplastic more ridgid and lighter still.