Somehow, long before the Wright brothers pioneered powered flight, the Native peoples of Australia discovered that a specific curved wing profile is essential for optimum boomerang flight. And it all has to do with how the leading and trailing edges of the boomerang arms are shaped.
Leading edges need to be curved down bluntly, while the trailing edges must taper gently. The bottom face of each wing is flat. The plans show the shape you need to make, and a random-orbit sander is the tool of choice for making the airfoil profile.
Start by taking note of how the leading and trailing edges aren’t the same on both wings of the boomerang. On one wing, the leading edge faces inward, while on the other, it faces outward.
Begin shaping work on one of the leading edges using a 100-grit disc. Work the machine back and forth until you create a smooth, blunt curve on the upper faces of the boomerang wings only. While it’s true that the top faces of both leading and trailing edges are curved, bottom faces of the wings must remain flat—just like the wings on some airplanes.As you sand, pay attention to the plywood layers that become exposed while the curve forms under the sander. These function as visual guides that help you create consistent results. If any part of the curve is uneven, you’ll see it in the form of wavy lamination lines. Smooth lines mean a smooth, consistent curve.
After you’ve tackled one leading edge, do the other one, then the two gently tapering trailing edges. (You’ll find the plywood laminations particularly helpful for creating a smooth taper here.) As a final step with the power sander, angle the bottom faces of the wing tips up over their last 11⁄2". This angle reduces wind resistance, leading to longer flights.
If you want flashy boomerangs, three or four coats of spray paint, sanded lightly between coats with 240-grit paper, create a new-car finish, although you can certainly leave your boomerangs bare too. They won’t look as nice, but they might just be more fun to play with if you don’t have to worry about preserving a finish. Either way, pick a big field to throw them in (at least as large as a football field), have everyone stand a few feet behind the thrower, then keep your eyes open. Boomerangs really do circle back as they arc through the sky.
Exposed lamination lines reveal the blunt and tapered curves that create the airfoil shape on each wing.
Taper the surface of each wing tip to reduce wind resistance.Throw-how
You'll bet optimal flights by grabbing one wing tip between your thumb and the side of your index finger, with the curved wing surface facing your face. The boomerang should look like an upside-down L. Throw the boomerang with the wings oriented vertically. It'll flatten out into a horizontal position as it flies, arcing around in a curve. The radius of the arc is determined by the angle at which you throw the boomerang relative to the horizon.
Steve Maxwell enjoys tossing a boomerang with his family (wife Mary and kids Robert, Katherine, Joseph and Jacob) on Manitoulin Island, Ont.
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