beetle kammback

[skyking]

The second image is close to what I want as far as the shape/attachment to what I have.
Snip it off right at the apex of the fender and that is what I have planned, with some of that curvaliciousness of that Colani trailing edge.
I can attach to that to reach back to the trailer on trailer days.
Thanks for the inspirations

[aerohead]

Yes,below the backlight,like the Harrod Helper and Ernie Roger's Bug wing.It helps compartmentalize the turbulence.
What freebeard has rendered in his upper drawing of #30 permalink is the idea.
Any of that length would help if it didn't interfere with the trailer.

[freebeard]

There are an infinite number of squircles between the circle and the square. One of them will be the closest match to the profile of the New Beetle at the A-pillar. These are not it*, at 50/50. Something about 65-75% toward a square would be closer. The rear quarter windows should be unobscured.

The lower body is held to the original overall length; the wheels are covered and the 'shoulder' is moved forward for aero reasons. The upper body is sized to the length of the rear hatch and could be extended.

*Truncated, widened and stretched to fit.

[skyking]

I'll park it for a week and mock up something in cardboard I can photograph. I know the shape I want and can make it better than I can draw it.
Thanks for your images and inspiration.

[freebeard]

It will be interesting to see what ou come up with. This was my first attempt at a mock-up, working with that external drip rail.



What I'm working with now are 16ft long redwood strips that go from the stagnation point to the rear in one sweep (on a different Beetle). I've learned some interesting things, but I don't have a camera right now.

[ECONORAM]

Originally Posted by skyking

that's not happening. It is more comfortable for my rear end than anything else I have driven. I did a 590 mile run the other day and I was not broken afterward.
My camry would have left me in shambles. only the full size diesel truck is as comfortable for me, and I like the economy of this one.

The older I get the more I can appreciate the comfort factor. I much prefer driving my truck to driving the wife's Avenger, even though the car gets better mpg.

I personally like the look of the sharky version. Deep or shallow doesn't seem to have as much "style". Not sure if there's an aero difference.

[skyking]

Freebeard's graphics have inspired me; I think I will go with two pieces now.
A front fixed fairing that starts aft of the sunroof, and the main piece which rides on the hatch. I have several small and large pieces of 1/8" Divinycell to play with.
I'll use 1" XPS foam to make bulkheads and hand shape them, then skin with divinycell strips.
Once I sand the joints smooth, I will coat it with epoxy with black pigment. This is to make sure the finished product looks good. It is easy to get small gaps in the carbon fiber cloth, and the green divinycell would look terribad.
Then I'll hand lay up the carbon/epoxy and coat it out clear till it looks reasonable.
I'll knock out almost all of the XPS bulkheads and put some light cloth on the inside.
Since early November I have been back at work again, many hours and even Sunday shifts. Needless to say, it cuts into any modding.

[skyking]

Originally Posted by freebeard

There are an infinite number of squircles between the circle and the square. One of them will be the closest match to the profile of the New Beetle at the A-pillar. These are not it*, at 50/50. Something about 65-75% toward a square would be closer. The rear quarter windows should be unobscured.

The lower body is held to the original overall length; the wheels are covered and the 'shoulder' is moved forward for aero reasons. The upper body is sized to the length of the rear hatch and could be extended.

*Truncated, widened and stretched to fit.

Freebeard, this image represents the initial profile of my trailer as I see it, thank you.
I hope to get the air stuck back onto it behind the beetle as soon as I can. The big challenge is how I can taper/transition the three curves into one that gets as template C-like as I can by the ending out of the trailer.
Washing out those sharp inside corners will be fun.

[freebeard]

I see mention of a trailer in the 'tapeee' thread. What trailer did you get?

'three curves' The top and two sides?

'sharp inside corners' I guess I'd need to see a picture. I don't know what other old posts you've found, so here's a comparison of [half-] circular, squircular and square cross-sections.



The square section has the worst cross-wind performance.

[aerohead]

The 'squircle' can produce as low a drag as a proper half-circle streamline body.
Jaray proved this as early as 1922.
Here are very different cross-sections of identical Cd