How to make a rubber band power paper plane

Materials and tools used: scissors, needle-nosed pliers, paper clips, glue, rubber bands, plastic straws and cardboard.

The first step is to process paper clips with needle-nosed pliers, as shown in the order of 1, 2, 3 and 4. Two paper clips should be processed in the same way. If you don't have needle-nosed pliers, you can use an ordinary household thread cutter, but it's a bit clumsy.

In figure 1, the paper clip is bent into a slender regular S shape, in figure 2, it is bent 90 degrees from the middle of the S shape, and in figure 3, the S shape is reset. Note that there is a small bend in the middle. These two paper clips are used to make helicopter rotor skeleton, and the small bend in the middle is the shaft.

Let's make helicopter rotor blades and cut them into four pieces with cardboard.

Glue the blades and the skeleton together, and the two rotors are finished. Note that paper clips are made of metal, and ordinary glue will not stick well. AB glue is the best, which is generally sold in supermarkets. 502 dry glue should be ok, but we won't know until we try it.

Plastic straws and rubber bands. Milk tea can be bought with a folding straw and a rubber band supermarket, and it costs 3 yuan for a big bag. Note that the length of the straw depends on the length of the rubber band, just a little longer than the rubber band just tightened.

Cut two opposite small gaps at one end of the straw with scissors, as shown by the red arrow in the figure.

Pass the rubber band through the suction pipe, and the two ends are respectively sleeved on the small bend in the middle of the helicopter rotor frame, and the rotor frame at the notch end of the suction pipe should be stuck in the notch. You can hook the rubber band with a bent wire to help finish the work. Three rubber bands can be connected in parallel.

Working principle of rubber band powered helicopter: the upper rotor is movable, and the lower rotor is stuck on the suction pipe because there is a gap in the suction pipe. Because the rubber band is slightly shorter than the straw, the two rotors are connected with the plastic straw through the tension of the rubber band. When the upper rotor rotates, the rubber belt in the suction pipe is tightened and the rotor is loosened. Under the action of the rubber band, the upper rotor, the lower rotor and the suction pipe rotate in opposite directions respectively. Note that the rubber band should not be pulled too tightly, otherwise the friction between the upper movable rotor and the suction pipe is too large, which is not conducive to rotation.