vjarnot

I think he epoxied it on.

mikegarrison

Jack, how thick is this ".86 gauge" anyway?

Flashing seems to be sold in both inch thickness (ie. .0120") or ".86 gauge" or ".92 gauge" or even "standard gauge". I'm guessing that might actually be .0086 inches, but I haven't been able to confirm that.

Standard sheet metal gauges are things like "24 gauge", which in aluminum is .02".

mikegarrison

Aha! Here's some info:

http://www.amerimax.com/productdetail.asp?...=81&iSubCatID=5

davepk

When you get the wing made from foam, have them cut 2 x 1" lengthwise vertical slots from tip to tip.

Place the slots at the 1/3 and 2/3 chord length position, or there abouts.

Then you can add a 1" diameter pipe, tip to tip, in each of the 2 slots.

That will provide all the stiffening you need along with mounting points internal to the wing.

This is a common build technique in model aircraft designs.

mikegarrison

Depends on how thick your airfoil is, but 1" may be too big to fit. I'm sure it's more than is necessary for strength.

Also, I would put my main spar at 1/4 chord. That tends to be approximately where the center of lift ends up.

JackOlsen

I'd have to cover over the old skin, which would add a little weight. Otherwise, I'd have to start from scratch -- my design was pretty simple.

I don't mind the little dents at all. But if someone tries to push the car by the wing the way they do in the pits at a real race, I'd be in trouble.

And by 1/4 chord, do you mean 1/4 of the way from the leading edge?

And vjarnot, there's no pressure. If I made progress on this in the next four months or so, I'd be surprised. Lots of other projects in line ahead of the 2.0 version of my wing.

Still, that insulation foam seems like a cost- and time-effective way to start a wing.

mikegarrison

Yes, though it actually means 1/4 of the way from the leading edge to the trailing edge *along the centerline of the airfoil*. The last bit is because a straight line between the LE and the TE is not the same as the centerline of the airfoil except for symmetric, uncambered airfoils.

skier219

Jack, I am curious, what drew you to that particular airfoil shape? BTW, as a historical note of interest, I work at the lab where they developed all of the NACA airfoils!

jzr

Heh, feels like only yesterday...you still got that old particle board wing lying around Dave? Getting a bigger garage next week (with a pretty nice house attached to it), and I'm setting aside some soom for a "wing museum". Let me know if you do and want to get rid of it, I'll be up in your neck of the woods around Thanksgiving.

Back on topic, I was able to get the guys at the foam place Jack mentioned to cut me both cores of a 2-element wing I had designed by "some guy in the UK". I got the main element finished, but priorities shifted before the wing was completed, so now it's a wing in need of a car. (No it's not for sale).

http://forums.freshalloy.com/showpost.php?...0&postcount=277

Antonov

Very cool. Interesting to see the use kevlar and uni-directional carbon, its going to be one stiff wing. Can't wait to see the final product. How do you plan on integrating the end plates and the wing mounts?

Dino