Building another wing for track use

[Jack Olsen]

An old 911 generates a lot of lift at speed. On a track, it's helpful to put some kind of wing on the back of the car (and a splitter up front) to keep the thing better-stuck at speed. I've had a bunch of different wings -- some of which I bought second-hand and some that I've made. The first was glued together out of aluminum and worked well, but was a pain in the neck to make. More recently, I've had EPS foam cores cut by a CNC hot wire cutting place and then skinned them, variously, with aluminum, heat-shrink stuff, packing tape, and even contact paper.

I had a wing fail last week, and now I want to try a different size of wing next. But the waiting time and price of getting a new core cut are enough that I've decided to try and cut my own with a primitive hot wire cutter that -- if it works -- will slice through (and seal) the foam, and give me a wing for not much more than the cost of a sheet of wall insulation.

The first step was testing to see if I had the stuff I needed to build a hot wire cutter. So I grabbed an AC wall adapter and a current-adjusting dimmer switch off from my deck, and clipped a piece of .023 wire from my MIG welder.

I think I'm going to document this project with video, so here's the first 3-minute clip of me awkwardly talking to a camera in my garage.



Let me know what you think of it. And anyone who knows more about this kind of project than me, please feel free to nudge me in the right direction where I'm doing stuff wrong.

[juanbenae]

jack has jumped the shark for no other reason than is there is too many new members that inhabit this place not aware of your godness...... haha...

[ipapilot]

Looking forward to the results of this one!

[Trackrash]

As usual, Jack takes DIY to a new level. I will anticipate the results.

I am thinking that using 1' long sections, cutting them to the airfoil shape, and gluing them together might be a strategy to consider.

[rothaus]

Jack, you got way to much time to play around... LOL

Cheers
Engelbert

[tctnd]

An old Lionel train transformer makes a good hot wire control unit.

regards,
Phil

[proffighter]

Hello Jack

Nice project! I have some expierences in cutting foam if you are interested. Made my own wing and door panels. Here you'll find some pics about them, just scroll down:

Another rust combat

PS I spent about 150USD for my DIY cutting bow (or how that's called in english)

[Helijohn]

Hello Jack

You can use piano or gitar wire for cutting.

[proffighter]

If you wanna build your own power supply (german sorry, but I guess info is usefull):

seite - Page: 30 of 105

And I tried other wire like guitar before, useless due the heat transfer, hot in the middle, cold at the sides. Use wire made for cutting, not expensive and way better results.

[Bergo]

nichrome wire is what you should probably be using, same stuff they use in a toaster.

[Taxi!]

Jack's next project will be finally getting around to build that flux capacitor.

[Alex973]

a small aircraft wing maybe? please show us the final product.
thanks

[Jack Olsen]

Thanks, guys.

I'm waiting on some nichrome wire now -- and looking at different ways aircraft guys do this.

Originally Posted by proffighter

Hello Jack

Nice project! I have some expierences in cutting foam if you are interested. Made my own wing and door panels. Here you'll find some pics about them, just scroll down:

Another rust combat

PS I spent about 150USD for my DIY cutting bow (or how that's called in english)

Wow! I hadn't seen the thread on your car. I just got lost in it for awhile. Very impressive!

[Kemo]

thanks for posting this... interesting idea, will you be wrapping in Carbon? Curious to see how all this fits together.

[Ferrino]

What about a hot-knife like this from Harbor Freight?

130 Watt Heavy Duty Hot Knife

[Cory M]

here's a nice diy carbon wing build from a BMW racer for reference:

Foam Carbon Fiber Wing...DIY

[douglas bray]

Jack, I'm in the protective packaging business and deal with hotwired EPS foam almost every day. My foam guy has the materials and CNC equipment to make anything you'd like. I'm thinking I could pull some strings, so to speak.

[joe payne]

What about a fiberglass GT2 Wing w/ the aluminum adjustable extensions capped off with a carbon fiber banana wing?

[ipapilot]

Great idea joe, let's make that two!

[Damon in STL]

Hi Jack,

I played with with a homemade foam cutter a while back.....and never could get a good consistent profile over a long span.

I noticed in your vid the foam wing you have has a hole for a center spar. Can you tell me where you purchased it? Also, have you tried different NACA profiles? If yes....which one did you settle on?

Damon in STL

Edit: BTW...here is a link to what I've been playing with aero wise on my M3
Bimmer Forums CFD Link