Kit Overview and Build the Tumblewing
Transcript of the narration below
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This video first gives an overview of the 7 gliders of 4 different designs that you can make with this kit. Then it shows you how to make the Bigmouth tumblewing.
Click on any picture or here http://www.youtube.com/watch?v=f-_H3GOBU20
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This kit contains enough material and patterns for making 7 foam gliders of 4 different designs that you can surf on waves of air. There are two of each of the 3 small gliders because—experience has taught me—people don’t pay close enough attention to instructions the first time through.
They're sequential, in other words each project builds on the ones before, so it’s a good idea to build them in order. The foam might have little holes in it and it’s ridiculously fragile, but that’s the price we pay for ultra light, super efficient gliders. Handle it gently.
The first video in this series is an introduction to these mysteriously levitated walkalong gliders
This second video starts with this overview of what you can make with this kit, then shows you how to use a big piece of foam for the easy-to-make and adjust, auto-gyrating, Big Mouth Glider. It shows you how to fly it by deflecting air with something big and flat. There’s enough foam for another if you break it.
The third video shows you how to make a Thompson Jagwing which uses a very unique aerodynamic trick for achieving lift. It uses a small foam sheet and it’s so efficient that, with practice, you might be able to levitate them using only your hands to make the air wave.
The forth video has instructions for using another small sheet to make a Baby Bug indoor hang glider. They get their efficient lift from subtle wing curve, called camber. It’s more challenging to get that airfoil shape, but again you’ll be rewarded with such performance that you can learn keep it up with your hands.
The fifth video shows you some advanced activities when you start getting good at flying. Aerial jousting or dog fighting is hugely fun and very aerobic. There are also some tips for achieving hands only flight.
In the sixth video, for a change of pace, your kit has some thin-as-hair nickel chromium wire that I use to slice the thin sheets of foam with. With a 9 volt battery and some tableware you can rig up a simple gizmo to cut shapes out of recycled foam. And—this might not be for everybody--but I’ll show you how you could use a small piece of plywood and some rubber bands to make the simplest, precise hot wire cutter I can think of. With it, you can slice sheets from discarded packaging foam you have around the house, to make more Jagwings and Baby Bugs.
Finally, the seventh video shows you how to use two big sheets to make a giant Mama Bug Glider. There is a Papa Bug glider—even bigger—but not in this kit and I don’t recommend it until you’ve successfully built the gilders in this kit.
Making the Big Mouth Tumblewing
The Big Mouth Tumblewing is the quickest and simplest glider to build and the easiest to learn how to air surf. Carefully cut out this pattern right on the outside, solid line. Put it on one of the foam sheets, even with the edges this way and with an equal amount of foam peeking out each end this way.
Using sticky tape that you can see lines through, tape the paper pattern to the foam. Do not fold the tape over the edge like this.
Cut on the long solid lines between the strips. You’ll use 2 strips for each tumblewing. Cut on the solid lines at the ends. The patterns fall off without any tape weighing down the foam.
Use small pieces of clear tape to tape the ends of 2 foam strips together. I’m just marking the tape for better visibility on camera. Transparent tape is the lightest weight, best for flying.
The glider will not fly as is. You have to curve it so it stays open a little, about 2 inches or 5 centimeters as you hold it sideways like this. You can pull it open like this or by curving it around your finger like this. Either way, be careful, you’ll see just how delicate this foam is. If it does break, fit it back together exactly and tape it with as little a piece of tape as you can. There are also two more strips for another glider.
Launching the Big Mouth Tumblewing
For launching you have to find a place with very still air. It’s almost never still enough outside, except perhaps at dawn and dusk.
Once you’ve got it to an oval, if you just drop the big mouth it will usually paddlewheel. The first thing to practice is getting it to paddlewheel away from you, not toward you and not to one side. For that, you need to know that tumblewings don’t rotate like wheels. If you roll something, the top rolls in the same direction as the wheel is going.
But tumblewings are contrary. The top is rotating opposite the direction it’s flying. The front keeps flipping up and over.
So launch like this. Hold it in the middle. Bend your wrist to make the bottom swing. Let go as the bottom swings away. You only have to move a little bit. If it always goes off to one side, you’re probably tilting it.
You might prefer launching it this way, holding together and pushing forward. See what works best. Practice launching until it tumbles away from you more often than backward or to the side.
Surfing the Big Mouth Tumblewing on a Wave of Air
Here’s where the real magic begins, but this part also requires the most practice. Don’t expect to get it in one day because there are so many things to remember at the same time.
You'll need something flat to create an air wave. This paper-sided foam board is the perfect size, 20 inches by 30 inches or about 50 by 75 centimeters. It’s rigid enough and light weight, but it can’t be rough handled. We recycle big pieces of cardboard, campaign signs, large flattened breakfast cereal boxes, even big books. Cereal boxes and books are harder to surf with because they don’t deflect as much air. But that could be a good thing to learn with because if forces you to position the tumblewing exactly right.
You will have to balance the tumblewing on a wave of air at the top. You will also have to continually balance it from blowing off to the side.
Here are tips, and the mistakes I made and all my students make when starting out.
Keep the tumblewing high on the board by going faster, not by tilting the board. Start with this angle almost vertical, the top tilted back just a bit. That intercepts a lot of air and deflects it up. Many people unconsciously start tilting back to lift the glider. That’s not good because your air wave gets smaller and you can’t sustain lift. We say, “Keep it a wall, not a floor!”
Make the glider go up by going faster and lifting the board up. It’s good practice to go so fast that it goes right over the board. Then slow down just enough that it doesn't go over.
The glider does not tell you where to go. By steering the board left or right, the air in front pushes the glider in the direction you want to go.
If you fly near other people they will make wind which will affect your glider. It’s called turbulence, and vents can also cause it.
There are 3 more things to remember: practice, practice and practice! It will take days or weeks to get good. But when you get it, it's like magic. You’ll amaze everyone, including yourself.
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