2000 GMC FastBack AeroCap Project

[MetroMPG]

Chaz: at this point in your build, you could confirm how well your shape is going to perform (or not - don't mean to jinx you!) fairly easily by skinning it with cardboard and duct tape and then tuft testing. Probably take you about one to 2 hours to do & gather the visuals needed to know for sure.

If you do it, have someone follow you with a video camera - or set up a camera on a boom attached to the rear of the truck, shooting forward like I did when I tested my boat tail:

[ccrider]

chaz your cap looks great you are really doing a great job with the construction of it the way you rounded corners and tapered the back in. i took the easy way out on my cap and just squared off the corner. i think yours will be allot more efficient than mine. the rounded corners and the taper is no easy task getting the plywood to bend. i am thinking that like you said there needs to be kerfs cut in the plywood back and i think you will end up with a few pie shaped pieces with kerfs cut in the back that will make up the sides of your cap. with the points of the pie shaped pieces ending at the back of the cap.

give me a call when you are in new york. now you have me jonesing for a gyro

[ccrider]

chaz one other thing you might want to consider while you are building your cap is putting a piece of plexi on the passenger side of your cap. i think that i am going to put a window in my passenger side because my truck has a blind spot on the passenger side when i am merging into traffic at a slight angle . it is not bad when the merge is at 90 degrees. your truck might not be as bad because you have a extra cab but i don't think it would be a bad thing to have a window on the passenger side

[ChazInMT]

Progress Report for ya. I got the skin on. What a pain, I think this now qualifies me as an Assistant to the Helper of a Novice Shipwright Apprentice.

Each of those 1" corner strips are quite different when laid flat. The sides really didn't like going on, it is a mess on the inside, But I'm happy so far with the result.

The cap isn't too heavy (50lbs I'd guess), but it is a pain to handle alone, there isn't a place to just grab it, it's awkward.

I'm such a futzer, this thing has taken many, many hours of work to get to this point. I think Fubeca and CCrider would kill me if they watched me working for how long this is taking. Wishing I had gone with a simpler design. This is the case with me however, figure out a hard way to do it, then change it often to make it even more complicated. I don't even want to give detailed advice anymore about this cause I doubt anyone will want to go this route to build something like this.

I have no provision for any viewports with this model, it's just a proof of concept/Lets see if the darn thing works deal. I do have an extended cab and am comfortable with just using my side view mirrors. I would definitely put in a rear window on anything I would use long term.

I am a little concerned now about the gap on top, the curve of the roof is just enough to where I'm afraid it will send air into the very top flat part of the cap and create turbulence and noise. I'm going to look into some magnetic sheets for making a gap filler or something.

[mjboks]

Nice work. Can't wait to read about the results.

[Fubeca]

It looks good! I am prone to futzing too - if I hadn't had a hard deadline, I would've spent many more hours making mine more refined.

[Bow]

Wow!

What a project. nice work!

[moorecomp]

Maybe you guys doing this should look at radius chine plywood boat builders. This is from one of the sites I follow:

August 2005 Build Photos

I am a sailor and a hypermiler.

[ChazInMT]

Craig, that's a great tip to lay the pieces at a diagonal like that. I was all excited about it and ran out to try and lay a scrap over my corners diagonally like that, and figured out my corners are too tightly radiused. The plywood didn't want to bend that much and broke. That trick is definitely something to keep in my hat though, so Thanks a Bunch for that tip.

[moorecomp]

They use 2 layers of 1/8th inch (3mm) on the boat. Not sure if you could find something called "Door Skin" plywood at HD or Lowes. It is 1/8th inch.