Switch points are the thin, machined rail ends that move together when a switch is thrown, one fitting tight against its stock rail while the other stands open. A point that does not close fully, called a gapped point, can let a wheel flange split the switch and derail the train. Crews check the point fit before running over a hand-thrown switch, because ice, snow or a stray rock wedged in the gap can hold them open.
Points aren't closing all the way on the east switch, there's ballast in there, give me a minute with the broom.
Snow and ice packed in the points are the classic winter failure, which is why busy main line switches carry gas or electric switch heaters.
Also heard as
- points
- switch rails
Related terms
Frog
The crossing piece in a turnout or diamond where one rail passes through another and wheels cross the gap.
Line
To throw a switch so it routes a train or car onto the intended track.
Derail
A device on a rail that lifts a rolling car's wheels off the track before it can reach another track.
On the ground
Derailed: off the rails with at least one wheel down on the ties or ballast.