Fig. 45.—A Home-made Motor Winder.
Fig. 46.—The Kind of Egg-beater to Use.
Fig. 47.—How the Motors are Connected to Winder for Winding.
Of course the rubber motors must be twisted an equal number of turns, in order to make the propellers work the same, and this is usually done with an ingenious winder made from an egg-beater, which winds both motors simultaneously.
The Home-made Motor-winder shown in [Fig. 45] is made from a Dover egg-beater ([Fig. 46]). To convert the egg-beater into a winder, it is necessary to cut off the loop ends and the center pivot wires on which the loops turn. Then bend the cut-off ends of the loops into hooks, and punch them to fit over the pivot wire ends, as before ([Fig. 45]). The ends of the pivot wires must be riveted to keep the hooks in position.
[Figure 47] shows
How the Egg-beater Winds the Motors. While an assistant supports the model by the propeller end, you remove the motor rings from the hooks on the bow of the fuselage, and slip them on to the hooks of the egg-beater. Then you turn the crank of the winder, counting the turns as you do so, and when you have wound the motors as far as you wish, slip off the motor rings, and slip them back on to the bow hooks of the model aeroplane. Motors of models like that shown in this chapter are wound one-thousand turns or more for each flight.
Wind the Motors Slowly, especially after the first row of knots begin, as it puts the rubber to the least amount of strain by doing this. Quick winding not only strains the rubber but makes the knots form in bunches, and uneven winding, of course, produces an uneven unwinding.
The propellers must be held after the motors have been wound, to keep them in check. [Figure 34] shows
The Position to Take for Launching a Model from the hand. The machine should not be thrown forward, as the movement would cause too great a disturbance of the air, resulting in the machine losing its stability, and probably upsetting. The best method is to give the model a slight push that will start it off at a speed a trifle under that produced by its propellers.