Windmills.—These are made in a great variety of forms. A few patterns which can be readily constructed of wood are given below. Bear in mind to make them strong, as they are under very great strain in a violent wind, and, also, that the larger they are the stronger they must be; for little models, you know, are much stronger in proportion than large structures made after the same designs. Dimensions are given merely to help illustrate the principles of construction. The windmills will work just as well if made larger or smaller, within any reasonable limits. They should be made of straight-grained white pine, whitewood, or some wood easy to work.[19]
Fig. 149.
Fig. 150.
Before beginning work read carefully Marking, Rule, Square, Saw, Knife, and Paring, and look up any other references. In case of using heavy stock, see also Draw-knife, Spokeshave, and Plane. To make a very simple form (Fig. 149), take two sticks, say 8" x 1" x 1", and halve or notch (see Halving) each piece at the centre (Fig. 150), so that when put together they will form a cross with arms of equal length. Bore a hole through both pieces at the centre to loosely fit the pin upon which the vanes are to turn (see Boring). Upon the ends of each stick mark diagonal lines (Fig. 150) slanting in opposite directions, or so that, if you revolve the cross edgeways and look in turn upon each of the four ends, the lines will all slant the same way. This is essential, for the next operation is to shave each of the sticks down towards these lines until perhaps 1/8" thick (Fig. 150), and you can readily see that if these vanes are not turned the same way the windmill will not revolve. When this shaping is done fasten the sticks together with brads (see Nailing). The remaining part is very simple (Fig. 151), perhaps 1' long and ½" thick, with the broad vane made thin, as the only object of this is to act as a weather-vane to keep the windmill headed toward the wind, and if made thick and heavy the whole affair will not balance well.
Fig. 151.
The revolving cross you can now fasten with a nail or screw upon the end of the part last made (Fig. 151) so that it will revolve freely. Find the point at which the whole windmill will balance over your finger or a stick, and bore a vertical hole through the horizontal stick at this point. Through this hole loosely screw or nail the windmill on the end of a stick, slightly rounded to prevent friction (Fig. 151). Sandpaper the whole with rather fine sandpaper (see Sandpaper).