A box should now be made from sheet iron to hold the transformer. The box should be of such dimensions that it will be at least 1/8 in. from the transformer at all points. This box should be provided with a cover that can be easily removed.
Fig. 18—Shape of Support
Now mount the transformer in the box by means of small bolts, that pass through the holes in the supports and holes in the bottom of the box. Two binding-posts can now be mounted on one end of the box, and insulated from it, to serve as terminals for the secondary winding. Two pieces of stranded No. 14 B. & S. gauge, rubber-covered copper wire should now be soldered to the terminals of the primary circuit and passed out through insulating bushings mounted in holes cut in the end of the box opposite to the one upon which the binding-posts were mounted. These heavy wires should be firmly fastened to the iron part of the transformer inside the box, so that any outside strain placed upon them will not, in time, break them loose from the smaller wires. Be sure to insulate all joints and wires well inside the box.
Fig. 19—Method of Clamping Transformer Together
A circuit can now be run from a 110-volt lighting or power circuit, observing the same rules as though you were wiring for lights, and connected to the heavy wires, or primary circuit. The binding-posts, or secondary winding should be connected to the bell circuit and the transformer is complete and ready to operate. You may have to change the adjustment of the bells, but after a little adjustment they will operate quite satisfactorily.
Mirror Hinged to Window Casing
A shaving mirror is usually placed on a window sash to avoid shadows as much as possible. This is very inconvenient and many times the mirror is broken by a fall. A good way to avoid shadows and have the mirror handy is to hinge it to the window casing. This can be done with screweyes, A, and screwhooks, B. The screweyes are turned into the frame of the mirror and the screwhooks into the window casing. Two screwhooks can also be turned into the casing on the opposite side of the window, if desired, so that the mirror can be used on either side.—Contributed by James D. McKenna, New Britain, Conn.