FIG. 28.—The Manchester Motor.
The field frame is supported by a "pedestal." The pedestal is formed by another strip, one-half inch wide, soldered to the field at right angles, underneath the joint in the lower pole piece.
The pedestal should be firmly soldered to the field, care being taken to see that the solder runs well into the joints. Then bend the ends of the pedestal down to form two "feet" as shown in the illustration. The feet should be bent so as to bring the center of the armature tunnel five-eighths of an inch above the base.
Two small holes should be bored in the pedestal, at each side, so that the motor can be screwed fast to a wooden base.
FIG. 30.—Details of the Field Frame.
Winding the Field—It will be necessary to proceed with the winding of this motor in a slightly different manner from that followed in making the other motors. The wire cannot be wound on as easily as before and it will be necessary to wind the required length of wire onto a small spool or bobbin, which can be passed through the field. Double cotton-covered wire is the best for the purpose. Either No. 25 or No. 26 B. & S. Gauge may be used. A strip of paper should be wrapped around the field frame at all points where the wire is liable to touch, so as to guard the insulation against possible abrasion.
Figure 32 shows the method which should be followed in winding the coils. Both parts of the winding should be started at the bottom of the field and wound in the direction indicated. "B" and "D" are the starting ends Wind on three layers of wire in each coil. The terminals, "B" and "C," should be connected together after the winding is finished.
The Armature—The method of making the armature is exactly the same as that which has already been described. Three strips of tin, one-half inch wide and one and one-half inches long are required. They are purposely made slightly longer than is actually necessary and are cut to length after the finish of the bending operations.
