I have made many ornithopters before and after the one I will show you how to make in this instructable, but this one is still one of my best because it is stronger than my lighter all-balsa wood ones.
This one is of the more conventional ornithopter layout, with flapping wings in the front and a birdlike triangular tail. There are other layouts which I may also decide to make instructables on, which have the elastic in front of the wings or have dragonfly wings or look like 1490s Leonardo da Vinci designs.
I make most of my ornithopter frames from balsa now because it greatly increases flight time but I doubt everybody who wants to make one of these has balsa wood, so this one is the better option for most people.
To make the ornithopter in this guide, you will require;
- Chopsticks (or kebab sticks)
- Thin wood of some kind (I use Ice-cream sticks or balsa offcuts)
- Pins or thin, stiff wire
- A thin tube (I use the insulation from a paperclip or a clutch-pencil tube) for the pin/wire to fit into.
- A plastic shopping bag/packet (NOT the stiff or thick plastic kind, only the very thin kind)
- Plastic (from an Ice-cream container or something) about 1 millimetre thick.
- A small bead to fit onto the pin/wire
- An energy-drink can (only aluminium cans will work, DON'T use a steel can)
- Sticky tape
- Strong glue
- An elastic / rubber band
- Craft knife or scalpel
I did not include measurements because (A) I don't use them and (B) Your ornithopter will probably be a different scale to mine. Use the photographs for scaling.
Step 1: The Frame
This part takes a bit of time to get right but it is pretty basic. Sorry I didn't take any pictures before these so I cannot show you how I made the parts of the frame, but I will explain it as well as I can.
The main fuselage beam (Labelled in first picture) Was an Ice-cream (Popsicle) stick which I trimmed to size and sanded. Try to keep it as light as possible without harming its structural integrity.
The part labelled "mast" is made in the same way, but it does not have to be as strong so lighten it more. The ratio between the main beam and this in length is about 2.5 to 1.
For the drive system, glue a small piece of wood under the main beam where shown and glue some kind of tube under it. I cannot be specific about the tube because I use whatever I have lying around at the time.
For the crankshaft, bend a pin or piece of stiff wire into the shown shape. Start with the hook end. Once the hook is the correct shape and balanced, put the other end of the wire/pin through the tube. Thread a small bead onto this end and bring the hook as close to the back of the tube as it will slide. Also slide the bead so that it touches the tube.
Hold the wire (in front of the bead) with narrow pliers and bend a 90* bend into the wire. Make sure the wire can easily turn inside the tube before continuing. Bend the wire again where it is shown in the picture (also at 90*). It is critical that you get the distance between the 2 bends correct and to scale otherwise the ornithopter will make either a very big or very limited flapping motion. Leave about 1.5cm (2/3 of an inch) sticking forward. Test-wind the crank to check that it moves freely.
For the tail "hook" I use Aluminium from a Red Bull can but you could also make a wire hook.
For the aluminium one, bend a small rectangular piece of can in half and trim the "open" side. Glue this to the back end of the beam after squeezing the metal around the end of the beam.
Cut a piece of bamboo from a chopstick, etc. to the right diameter (guess which diameter will be strong enough, but lightweight) for the central wing rib. It must be the same length as the main beam. Glue it to the top of the "mast" in line with the main beam.