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Facing Point Lock .
Facing Point Lock. A Facing Point Lock (FPL) is fitted to all facing point connections that carry passenger services to ensure the points are locked in place before a train is signalled over the route, they remain locked until the signalman needs to move the point again but cannot be moved until unlocked and cannot be unlocked wilst a train is on the line. Only once the train has passed a clearing point beyond the locked points can they be unlocked and the route changed. The locking mechanism locks into slots in the point blade tie-bar ensuring the point is fully home against the stock rail, any misalignment, blockage or breakage would stop the slot lining up to the locking pin/bar and the points would not lock. If the point could not be locked the interlocking in the signalbox or external interlocking with slotted slides would stop the signals from being set to clear. The points are also fitted with detector units to provide a positive indication that the point blades are set correctly and locked in position ready for traffic. The two boxes beside the points just beyond the running rails are detectors required for electrical proving of the point blades position.
W orking model facing point locks are easily made in 7mm O gauge and larger scales and can be made for 4mm scale `OO' 16.5mm gauge with a bit of care & lots of patience. I have made dummy fpl mechanisms for my 2mm Ngauge layout using scraps of wire and fine brass strip.
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