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Old 07-02-2014, 06:33 PM   #31 (permalink)
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Herbird. Most people from truckers to campers want to have maximum usable space. A pointy rear shape is bad for that. Also remember that it has only been in the last 10 years that fuel prices have become outrageous. I sold my motorhome when the price went to $1.75, outrageous.

I have been moving for some months. We use a 12 foot 4 wheel flat bed trailer behind our OD vehicle. To enclose it in an ice cream cone would be fruitless.

Once things become stable here we plan on modifying our two wheel motorcycle trailer with an aero shape. It will be a steel frame and maybe a metal skin like a semi-trailer. Welding steel is so easy and light weight I couldn't imagine making one from wood.

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Old 07-02-2014, 08:14 PM   #32 (permalink)
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A pointy rear is really just a square turned 45 degrees. I figure I will use the space like a v-berth on the front of a boat but in the back instead, also with feet to the back the tapering headroom won't be a problem there either. As long as I have a 4' long by 6' wide price of floor with 6' headroom in the middle I'll be happy. Then a sleeping pod section maybe with hybrid style tent pop outs. The smaller of modern box trailers are 8' wide, 12' long with 6.5' headroom front to back, so much more then a couple needs IMO. Boat builders use space well, I'm thinking more like that while not killing the economy not to mention the mechanicals of the tow vehicle to the point I can't afford to go out for a week or weekend. I can't go too crazy with the radiuses or it will be to difficult to build.
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Old 07-03-2014, 01:48 AM   #33 (permalink)
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Quote:
A pointy rear is really just a square turned 45 degrees.
Actually a better comparison would be: en.wikipedia.org/wiki/Vesica_piscis



Here is a design where the radiuses couldn't be gentler. It's actually a good approximation of the Template shape, stretched vertically.

Just the opposite of the Bowlus; the door is at the rear, in a truncation. The pointy end has a 90° angle in the front. Here's the frame laid over a teardrop outline.

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Old 07-22-2014, 09:13 PM   #34 (permalink)
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Frame1

Frame2

Rear left

Rear open

Rear open 2

Comments from builder's brother:

"Full round front nose. Should weight 1200 empty"

"He built scale models and a 6 foot windtunnel to design the shape. He's pretty sure it'll help get as good or better mileage vs. The towing vehicle by itself."

"The drag coefficient with his full-to-a-point trailer design is so crazy low....its really more about how you put the air back together than how you take it apart. He saw Lower drag (in models) with trailer than without..... and he theorizes that it'll be quite a bit more dramatic at full scale, obviously."

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Old 07-22-2014, 09:32 PM   #35 (permalink)
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Behind a full sized van that might work ennored, behind that little car it looks like a whale.
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Old 07-22-2014, 11:30 PM   #36 (permalink)
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A great, white whale.

I'd split the tail and put each side on 4-bar linkages so they swing out and forward. Like a minivan door before it starts to slide. It might not work without taper to the top.
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Old 07-23-2014, 10:35 AM   #37 (permalink)
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It has some taper on the top, but not much. It was obviously designed to be able to made easily, all flat sheet aluminum. And to be able to get a car into it.

Given that a square box can have a drag coefficient as high as .8 or more, this should pull great. Try towing a regular enclosed car trailer with a Nissan Maxima, ain't gonna work.
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Old 07-23-2014, 01:17 PM   #38 (permalink)
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I like that trailer, taper the top some, put a door and some Windows on it, dont need the ramp and rear doors, and that's what I'm thinking. Look at how low it rides compared to the average camper, the up sweep on the rear help with overhangs and aero. Still tons of space inside.
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Old 07-23-2014, 01:29 PM   #39 (permalink)
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That's a well-used race car.

The truss work and triangulation in the side walls look good. The air bag doesn't point at the trailing arm; maybe there's a rocker arm in there.

Did you see this or just find the pictures? I'm curious whether they left the lower rear open. And how they get the car in and out.
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Old 07-23-2014, 01:47 PM   #40 (permalink)
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Found it in another forum.

There's a "floor" that drops down from the right side rear door. The air suspension lets the tail of the trailer drop right to the ground. It's dropped in the "Frame2" linked picture.

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