Have a go at creating a boomerang.
Those of an addictive or compulsive nature probably shouldn't try to fly one!
Of course, you'll need to test fly and make adjustments before you achieve the perfect boomerang performance, but surely that's half the fun!
Included sketches should help you visualize the aerodynamic profiles required.
My YouTube video might help too (https://youtu.be/xffY17fQAws).
Step 1: Begin the Build
Start by cutting two 13" lengths of pallet slats. Thin slats, about ½" would be good, and about 4" wide.
Cut the ends of your boards at 110° (that works well for me, but to be honest I'm not sure it's that critical!)
Line the angled ends up with the edges, and mark out for the halving joint (half lap)
Step 2: Rough Cut Halving Joint and Outline
Remove the bulk of the waste for the halving joint
Place the joint together and mark out the outline of the boomerang - I'm using my X-Carve boomerang as a template, but you could blow-up one of the drawings (included later) and use that. If you do so, fold the drawing over so the arms line up as best as possible, then cut around one arm outline. This will ensure symmetry, which is unlikely to be present in my sketches!
Cut out the rough shape of the boomerang, leaving a little to clean up later
Step 3: Make a Good Joint
Unless the halving joint is made well, it is likely to fail if the boomerang lands hard on one if it's arms
The secret to a well made, and therefore strong, joint, is maximum contact between the wood surfaces. To achieve this, clean up the two mating surfaces so that they are flat and smooth
Glue, and clamp until fully cured
Step 4: Clean Up the Blank
Sand and plane the glued up boomerang blank until it is perfectly flat both sides, and all the sides are square to the faces and smooth - this makes marking out for the aerodynamic shaping a lot easier
Hopefully the boomerang will balance nicely from the centre of the arms - aim to maintain this during further shaping
Step 5: Mark Out the Aerodynamic Profiles
Use the drawings to help you mark out for shaping the surfaces of the boomerang
These drawings are for a right-handed boomerang - one thrown with the right hand, that should fly a circle in front of the thrower. To make a leftie, you should layout as a mirror image to the drawings
Step 6: Profile the Boomerang
Following the marking out, shape the profile of the boomerang
I found a block plane perfect for the flat chamfers on the flat side, and a mixture of block plane, spoke shaves, rasps, and files, for the opposite side
Smooth everything with abrasive paper
Step 7: Ready for a Test Flight?
Before flying the boomerang, I give it a coat of sealer. This protects it absorbing moisture, and makes it easier to clean if your park is shared by pets!
Find a large open expanse, on a day without wind, and give it a few throws
- Hold like a hammer, vertically, with flat side to palm, and other end facing forwards
- Throw forwards, imparting a top spin
- The spin creates the lift, and is the most important factor - build up the strength of throw once you've cracked the spin
Note how the boomerang moves in the air
- The main profiling on the curved face of the boomerang arms should give 'lift' away from the flat side when the boomerang is rotating in an anti-clockwise direction (as thrown)
- Bevels towards the leading edges of the flat sides (from the middle of the ends to about 1/3 the way to the bend) help maintain a horizontal flight
Decide if you need to make any adjustments. If you do, make them slowly, test flying often to prevent you going too far
The goal is a boomerang that climbs a little as it levels itself, curves around in front of you, and descends slowly as it returns to your hand - Good Luck!
I am in no way an expert in boomerangs or aerodynamics, but this was how I managed to make one that comes back - usually!
Thanks for reading my Instructable. I hope you enjoyed it.
Step 8: Test Flight and Tweaks
Watch how I adjust after a test flight.
It wasn't completing a full circuit, so I figured it was either too heavy, or didn't have sufficient lift to keep it airborne long enough.
After loosing some weight, it now comes back!
I shall attempt further modifications when Spring arrives.