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Old 10-10-2018, 03:25 PM   #21 (permalink)
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I'd be remiss if I didn't repost this one. It is a unibody isn't it? I apologize for not Photoshopping this into something comprehendible:



If you find a derelict cab that uses the same door you could cut the door frames down into a pie-shaped piece and slip it inside the half-open door and weld 'er up.

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Old 10-11-2018, 02:14 PM   #22 (permalink)
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If its american ambulance, it will be conventional truck frame & cab, probably a standard box also. Lotsa parts available. Worst case pick a part is your new friend
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Old 10-11-2018, 09:07 PM   #23 (permalink)
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I found this.

12v Cummins with stacks & fairing


Quote:
The fairing (aka roof wind deflector / spoiler) was purchased from a semi truck garage and pro fairing installer near here. It originally came off a DAF CF semi truck. While the front was okay, the rear section was too wide. So I took it to Body & Tuning in Mansfield and they did exactly the way I wanted it, perfectly. It still keeps the functionality of being adjustable, going up and down - here at its lowest setting for normal driving, being adjusted to the highest setting while towing the big travel trailer seen in the video, which is also my everyday living home. I installed it myself with four thick reinforced steel plates on the inside of the roof, cushioned with thick rubber to avoid scratching and noise.
New FWC camper, wind fairing suggestions
http://www.wanderthewest.com/forum/t...g-suggestions/

Quote:
I have a wind deflector on my Tundra. Honestly it does nothing for the mpg, what it does do is keep the wind noise down. I have a pretty good gap between the cab and the overhang and had very annoying howling going on at most common driving speeds with the deflector that has gone away. I found the fairing on the local craigslist and had to adapt the attachment to get it on the truck.

http://www.airodyne.com/collapsible.asp


One could set up some temporary plywood forms and wire fanfold insulation to them, then resin and glass over it. However a found item that is modified could also work.

I looked up basement window well covers, but could find nothing wide enough, was thinking one could fiberglass cloth and resin over it.

Bouyancy blocks (big chunks of rigid insulation) for floating docks could be glued and carved up to desired shape, but those blocks can get expensive and it's going to make a great mess.
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1977 Porsche 911s Targa
1998 Chevy S-10 Pick-Up truck
1989 Scat II HP Hovercraft

Chin Spoiler:
http://forums.pelicanparts.com/off-t...effective.html

Rear Spoiler Pick Up Truck
http://forums.pelicanparts.com/off-t...xperiment.html

Roof Wing
http://ecomodder.com/forum/showthrea...1-a-19525.html

Last edited by kach22i; 10-11-2018 at 09:17 PM..
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Old 10-12-2018, 12:03 PM   #24 (permalink)
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If you don't look forward to tiny fiberglass needles in your skin and breathing toxic vapors, consider Nudo Polymetal or Grimco Max-Metal as a material.



These samples were sheared, rolled and braked with a hand operated tool with an 18" lever arm. Braking the short edge ruptured the metal skin on the outside. Scoring the inside first might alleviate that.

The result is pre-finished, no filling and sanding needed.
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Old 10-12-2018, 03:00 PM   #25 (permalink)
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Great idea, I saw that being used on a job site sign ten years ago and thought it had great potential as an ecomodding material.

Limited to 2D bending, but that's what folding tabs and joint fillers are for, right?

I've only bent the non-alum skin version before.

https://www.boatdesign.net/threads/t...ruction.21403/
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George
Architect, Artist and Designer of Objects

1977 Porsche 911s Targa
1998 Chevy S-10 Pick-Up truck
1989 Scat II HP Hovercraft

Chin Spoiler:
http://forums.pelicanparts.com/off-t...effective.html

Rear Spoiler Pick Up Truck
http://forums.pelicanparts.com/off-t...xperiment.html

Roof Wing
http://ecomodder.com/forum/showthrea...1-a-19525.html

Last edited by kach22i; 10-12-2018 at 03:06 PM..
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Old 10-12-2018, 04:02 PM   #26 (permalink)
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Remember the accepted roundness for leading edges is a radius of 4% of the width. That'd be 4" for a 100" wide box. Looking at picture of the ambulance, it appears to already have that on the box. Can't really see it much though. OP?? If it's already radiused, I'm not sure there's anything to be gained there.
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Old 10-12-2018, 04:48 PM   #27 (permalink)
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OP posted three times total, but not in the last 48 hours, FWIW.

U-Haul trailers are optimal, the example in the one photo we all struggle with looks a little tight to me. Maybe 3"?
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Old 10-12-2018, 04:54 PM   #28 (permalink)
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Quote:
Originally Posted by ennored View Post
Remember the accepted roundness for leading edges is a radius of 4% of the width. That'd be 4" for a 100" wide box. Looking at picture of the ambulance, it appears to already have that on the box. Can't really see it much though. OP?? If it's already radiused, I'm not sure there's anything to be gained there.
Good point, but just rounding the corner edges to the optional roundness isn't the same or effective and a whole body approach that includes a massive roof top faring.

No one is going to claim that a cube with radius edges is as aerodynamic as a teardrop shape for instance.

He has one good detail on the truck, but as a whole it is flawed in every way possible.

It makes for an excellent ecomodder challenge though.

EDIT:

Look at the big rig fairings I posted, if just rounding the edges of the tractor trailer boxes was truly optimum then why would anyone strive for a better fairing?
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George
Architect, Artist and Designer of Objects

1977 Porsche 911s Targa
1998 Chevy S-10 Pick-Up truck
1989 Scat II HP Hovercraft

Chin Spoiler:
http://forums.pelicanparts.com/off-t...effective.html

Rear Spoiler Pick Up Truck
http://forums.pelicanparts.com/off-t...xperiment.html

Roof Wing
http://ecomodder.com/forum/showthrea...1-a-19525.html
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Old 10-12-2018, 05:58 PM   #29 (permalink)
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https://upload.wikimedia.org/wikiped...Colani-LKW.jpg

Tilt the Colania bubble back as appropriate. The three-bladed wiper might need cyclic pitch control.
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Old 10-12-2018, 07:08 PM   #30 (permalink)
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Quote:
Originally Posted by Farraider View Post
Regarding Sprinters, they're too common and have no character IMO - I like this vehicle and I did all the work myself.
OK, but that character is gonna cost ya ...

Quote:
Euromodder, your suggestion about rounding the corners more with half pipe. Half a 6 or 8 inch pvc pipe just mounted down the corners? With middle of the curve directly over the corner?
No, that would make the box even wider
You really don't want any more frontal area when you can avoid it

With the half pipe entirely on the front of the box

Doing the same on the roof might work too, despite a bit more frontal area
(the area of 1 pipe diameter)
Essentially creating a channel guiding the air aft.
With less air spilling over to the sides along the length of the box.
And what spills over, goes over more smoothly due to the bigger radius of the pipe than the box's original corners.

To be combined with a cab roof spoiler guiding the air to that channel


Quote:
I wonder how much that would help? It probably pales in comparison to fixing that huge flat front and rear drag.
It won't be the miracle solution, but your box could use any help


Not much of a creative talent here, but these quick drawings may give you the idea :

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