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The Boy Mechanic: Volume 1 - 700 Things for Boys to Do by Popular Mechanics Co.
page 93 of 996 (09%)
means of a U-bolt or large staple, E.
--Contributed by Carson Birkhead, Moorhead, Miss.



** Controller for a Small Motor [42]

An easy way of making a controlling and reversing device for small
motors is as follows:

Cut a piece of wood (A) about 6 in. by 4-1/2 in., and 1/4 in.
thick, and another piece (B) 6 in. by 1 in., and 1/4 in. thick.
Drive a nail through this near the center for a pivot (C). To the
under side of one end nail a copper brush (D) to extend out about
an inch. On the upper side, at the same end, nail another brush
(E) so that it projects at both sides and is bent down to the
level of the end brush. Then on the board put

[Illustration: Reverse for Motor]

a semi-circle of brass-headed tacks as shown at F, leaving a small
space at the middle and placing five tacks on either side, so that
the end brush will come in contact with each one. Connect these
tacks on the under side of the board with coils of German-silver
wire, using about 8 in. of wire to each coil. Fix these by
soldering or bending over the ends of the tacks. Then nail two
strips of copper (G) in such position that the side brush will
remain on the one as long as the end brush remains on the tacks on
that side.

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