When the Portland area Max trains opened up between Portland and Hillsboro, I became a frequent rail commuter.
Hidden engineering problems & solutions
July 28, 2007
Just past the Sunset stop, I remember being amused by a water sprinkler system that came on just as trains passed. “why?” I thought.
Then, at another turn in the track, I heard the train squealing loudly.
Why do trains squeal around corners? After thinking about it, I decided it’s because they don’t have differentials which would allow the inside wheel to turn more slowly than the outside wheel. So they go the same speed around the corner, and the squealing is the sound of metal-on-metal friction, which is inefficient, noisy, and bad for the wheels and tracks (I imagine).
Later, I noticed the sprinklers had been disconnected. “Hmmm. They must have figured something else out”
This week, at the Beaverton Central stop (where I work), I noticed an industrial white tub being used as a trashcan. It was labeled “SoyTrack Rail Curve Lubricant”. It made me smile.