at the bottom. A cross bar, L, made of the same
material, is fitted into the off-set in the frame and riveted.
Holes are drilled through the frame and brass bushings, H and J,
are fitted for bearings to receive the adjusting brass rod, B,
which should be 1/4 in. in diameter. A brass curtain rod can be
used for the rod B, and on its lower end a socket, P, is soldered.
A piece of brass 2 in. long, 1/2 in. wide and 1/8 in. thick is
used for the armature, A, to be operated by the magnet coil, C.
The coil, C, is made in the usual manner by wrapping No. 14
cotton-covered magnet wire on a wooden spool that has a soft iron
core. The spool is about 2-1/2 in. long. The armature, A, is
drilled, making a hole just a little larger than the rod, B, and
is adjusted in place by two set screws, D and E. A soft piece of
iron, F, is fastened to the opposite end of the armature with a
screw, which should be placed directly under the end of the coil's
core. This end of the armature may be kept from swinging around by
placing it between a U-shaped piece of brass fastened to the cross
piece L. At the bottom end of the frame, and directly centering
the holes H and J, a hole is drilled to receive a hard rubber
bushing, R, for insulating the brass ferrule, S, that holds the
lower carbon.
Pages:
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328