MetroMPG's Honda Insight boat tail extension (cardboard) tuft video; ABA test +9.7%

[ECONORAM]

Originally Posted by skyl4rk

Originally Posted by skyl4rk
*checks for tail*

I, too, am troubled by my lack of a tail.

I know I am buffeting my way through the atmosphere when I could be slicing through it. I could be saving at least 10% in fuel with a proper trailing edge. I could be passing through the dense fog with far less disturbance to the universe, yet still get where I am going quickly.

I may join thee in this quest for a proper termination of the vehicle body.

You all have me rethinking about it. I have been scavenging 1" foam board scraps from construction sites, to make one...but cardboard. Hmmm.

Originally Posted by 3-Wheeler

Hi,

Actually I think your savings would be way higher than 10%.

The "closing edges" of the Insight are way smaller than the typical car already, so comparatively speaking, the Insight has less of a gain by adding the tail.

A typical vehicle however, has more of a "square back-end" which means the addition of a tail has a much greater energy recovery based on the larger closing area before the tail is added.

If one happened to drive on the freeway a lot, then of course the gas savings are even higher based on the higher air speed.

Jim.

The back end of my truck with topper is about a full sheet of plywood. If I can gain over 10% from this. WOW.

Originally Posted by IsaacCarlson

You are a cardboard artist. That looks great! I would be ashamed to replace it with anything else. Just fiberglass over it like has been said many times before. I will likely fiberglass the gaps on my trailing edge, but it is not cardboard.....yet

I agree. Nice workmanship. Metro, I'm with you. Even when I do a prototype it has to last six months because I can't always find time to make a permanent version...

Originally Posted by cRiPpLe_rOoStEr

Want a cheap weatherproofing? Stickerbomb it

That is actually a good idea. We send my wife's family stuff in boxes, and it rains quite often where they live. So, we cover the entire box with clear or brown packing tape. Haven't had a box fall apart yet since we started doing that. You might want to paint it your favorite color first though...

[euromodder]

Originally Posted by MetroMPG

The less good news: I think the side curvature is a bit too aggressive. There's quite a bit of turbulence in those last 3 tuft columns. They dance around quite a bit, sometimes off the surface, though they never point "in to" the flow, so we don't have reversal (worst case scenario).

Try very small vortex generators.
Put them where the air is still going smoothly over the tail.

A 5mm thick cardboard zig-zag strip taped on should do the trick.

[Xist]

Originally Posted by euromodder

Try very small vortex generators.
Put them where the air is still going smoothly over the tail.

A 5mm thick cardboard zig-zag strip taped on should do the trick.

Has anyone tuft-tested zig-zags?

[freebeard]

Has anyone got an example of 'zig-zags'?

[MetroMPG]

Originally Posted by Xist

paint it... cardboard brown!

Coincidentally... started painting the tail this weekend with some leftover oil based paint I found in the garage... and it's light brown. Almost the same as the cardboard!

(Nothing photo worthy.)

Probably a couple of days to do 2 coats inside and out, then wrap it all in a plastic skin. I still have to look around Home Depot to see what options they have for something a bit sturdier than trash bag plastic, which is what I used to cover the Flea's test tail .

[cRiPpLe_rOoStEr]

Originally Posted by ECONORAM

We send my wife's family stuff in boxes, and it rains quite often where they live. So, we cover the entire box with clear or brown packing tape. Haven't had a box fall apart yet since we started doing that. You might want to paint it your favorite color first though...

I was actually referring to the stickerbomb trend that became usual among ricers. They can almost cover an entire car body with stickers, or a bigger one simulating various random stickers.

[euromodder]

Originally Posted by freebeard

Has anyone got an example of 'zig-zags'?

[Prophecy99]

holy cow, props MetroMPG! congrats

[Xist]

Originally Posted by euromodder

You would attach those with cloth glue?

[aerohead]

Originally Posted by freebeard

Has anyone got an example of 'zig-zags'?

I've only seen it in Kit Plane Magazine.They did an article on it,attaching it to propellers and landing gear struts.