Macskyver

Fairly recently I decided to set up my truck for overlanding/road trips. And since I needed a place to sleep and I don't want to mess with setting up/taking down a tent every day during trips, I decided a camper shell was probably the best way to go. And since camper shells are expensive and it is hard to find used ones for appropriate vehicle specific models, I decided it would be fun to make my own. And since I am making my own camper shell, I figured I might as well try to make it aerodynamic and squeeze as much fuel efficiency that is reasonable in an overlanding type vehicle.

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Macskyver

Just for reference, the best economy I have gotten out of the truck (2005 Toyota Tundra Access Cab 4x4) is about 22 mpg (highway @ 60 mph). It used to average about 18-20 mpg highway/freeway. Then after the installation of a home-made deer-resistant front bumper and larger than stock meaty all-terrain tires (285 75r16), the economy dropped to about 15-16 mpg highway/freeway. I have since dropped to a smaller (265 75r16) and much more highway oriented tire, so I bet that will give me a little bump, but I haven't driven enough miles to know the effect. My hope is to end up back around 20 mpg with the aeroshell mod and new tires. The desired gains are not extreme by any means, but will definitely be beneficial.

Macskyver

Anyways, on to the build... Basically I am making a cedar strip shell using similar construction techniques as the cedar strip canoes. I started by taking a picture of the back of the truck cab to get the profile, converted it to a vector graphic, and then imported it to Fusion 360. From there, I did a bunch of CAD work to get the frame of the shell designed.

Macskyver

I then cut all the frame pieces on the CNC out of poplar. The bit was a little smaller than nominal so some of the joints didn't fit very well. Overall it turned out pretty good though.

Macskyver

After that, I assembled the frame... pictures to come soon..

Macskyver

Now that I have 5 posts, I can start adding pictures.. Here is the CAD drawing:

Here is the frame in various stages of construction:



Finally, here it is mocked up on the truck:





I messed up a little bit on the contour at the cab. It doesn't line up perfectly and has a shallower more rounded curve at the corners. I should have checked it before making everything, but I didn't and this is where I am at. I keep telling myself that since the cab corners are kinda rounded the airflow will follow them a little bit before separating and this point is probably exactly where my camper shell starts. So this is really a feature and will make it more aerodynamic. Yeah, probably wishful thinking.. Oh well..

freebeard

That's really nice work.

What is the purpose of the two slots on the front and rear ribs?

Is the angle of the shadow on the back of the cab because the cab slants forward?

Macskyver

Thanks. The slots are for air vents. Eventually they will be covered with screens. I am not sure what shadow you are talking about, but the cab does slant forward a couple inches. I am going to extend the cedar strips past the end ribs to make eaves. The front eave will follow the cab slant. There will be a uniform 1" ish gap between the shell and cab when all is said and done.

BamZipPow

Great work! Where about in Texas are you?

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Macskyver

I am in San Marcos.