Signals Motors
To operate semaphore signals we have, at various times, used three different methods.
Solenoid Coils.
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The coils were manufactured by a club member. Threaded
brass rod was drilled to take the moving armature. Paxolin
discs were threaded and screwed onto the rod and the rod
was then covered with insulating tape. The coils were
wound using wire from old relays. A piece of PCB board
was fixed to one end forming a base and the coil
wires terminated to it. On the design shown the
signals can be assembled and adjusted on the bench as
a unit before fitting to the layout.
On Talybont these coils are also used to power uncoupling ramps.
As an alternative to making the coils it might be possible
to use the coils from SEEP uncouplers.
Relays.
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Small relays were modified by soldering an arm to the armature and a slot cut in the casing to allow the arm to pass through. The relays are strapped under the baseboards below the signal and the operating wires from it connected to the arms.
Memory Wire.
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Memory wire has the interesting property of contracting when heated and will, if tensioned by a spring, return to its original length when allowed to cool. The heating is achieved by passing a controlled electric current through the wire.
Our motors are manufactured from aluminium angle some of which, appropriately, came from redundant signal relay racking. The wire, cranks and springs were supplied by C + L Finescale.
