TIPS FOR FINE TUNING YOUR BOOMERANG'S FLIGHT
...IT'S EASY!
Flexing the wing tips in an upward direction is called "Adding Positive Dihedral." This will cause the boomerang to fly higher. The most common problem a new boomerang is likely to have, is a negative warp in the wing's dihedral, thus causing it to crash in front of the thrower. Flexing it up like this, should correct such a problem. To lower the height at the end of the flight, bend down the trailing wing (that’s the left wing for you right-handers).
Another method that accomplishes the same effect of adding lift, is to tape a small coin to the upper surface of the Dingle Wing....This is almost ALWAYS a sure-fire method to correct a diving boomerang. You may need to move the coin around a bit, in order to get the desired amount of lift. My suggestion is to simply start with the coin halfway between the tip and elbow, and reposition it using trial and error after that, until you get the lift you want. You don't need an advanced degree in Aeronautics to tune the dive out of your boomerang!
To make the boomerang fly a more circular path (and thus shorten its range), twist extra angle-of-attack into the lead (right) wing. This is done by twisting the tip of a right handed boomerang in a counterclockwise direction. To make it straighten out at the end, (thus, it'll fly more elliptical), reduce the angle of attack of the trailing (left) wing. On a right handed boomerang, this requires for the twist to be clockwise in direction.
Another method that accomplishes the same effect of adding lift, is to tape a small coin to the upper surface of the Dingle Wing....This is almost ALWAYS a sure-fire method to correct a diving boomerang. You may need to move the coin around a bit, in order to get the desired amount of lift. My suggestion is to simply start with the coin halfway between the tip and elbow, and reposition it using trial and error after that, until you get the lift you want. You don't need an advanced degree in Aeronautics to tune the dive out of your boomerang!
To make the boomerang fly a more circular path (and thus shorten its range), twist extra angle-of-attack into the lead (right) wing. This is done by twisting the tip of a right handed boomerang in a counterclockwise direction. To make it straighten out at the end, (thus, it'll fly more elliptical), reduce the angle of attack of the trailing (left) wing. On a right handed boomerang, this requires for the twist to be clockwise in direction.
Of course, these are generalizations of how tuning is done, and may not be quite that simple. If for example, you increase the angle of attack on the leading wing, you’re likely to introduce a bit of extra lift as well. So to “simply” reduce the range, you might need to bend down that leading wing as well. Having said that, you should always try to do any tuning with one application at a time, at least until you’re relatively good at it.
Sometimes, it’s easier to “tune your throw” to get your desired effect. An example of this would be using more layover to accomplish greater lift, like in the situation of near calm conditions.
To avoid breaking your boomerangs, you should remember that different materials accept and hold tunes differently. A thicker, stronger Phenolic Rang will take, and hold moderately well, just about any tune you might want to bend into it, but not so much if it's cold outside. Plywood may not be subject to temperature differences as much as Phenolic does, but it too can be fragile, if bent to hard or too much.
If you want to tune a plywood boomerang in a more permanent way, try heating it up for several seconds above a gas flame of a stove, a steaming saucepan, or in a microwave. In the case of most microwaves, I would suggest to start with a heating time of under 10 seconds. This momentarily softens the glue between the plys — bend the boomerang to the desired shape and place it under a cold tap water for a few moments, holding it in the position you want. Again, caution is recommended, and don’t be too attached to the paint job as it may get damaged in doing this. If your boomerang has lead or other metal weights, don't be a moron....DON'T HEAT IT IN THE MICROWAVE!
For tuning, you'll just need to experiment, and find the method that works best for you!
MANY HAPPY RETURNS!
BILL GLOVER