Originally Posted by Blaze
I'm always amazed at the size of those drive wheels when workers stand next to them.
I watched a show on the Southern Pacific Daylight. One of the most beautiful of the fully restored steam locomotives. The engineer said that every steam locomotive has what is termed reciprocating mass.
That is the part of the running gear that goes back and forth, not round and round. The reciprocating mass on the Southern Pacific Daylight weighed 6,000 pounds on each side. He said when the train is going down the track at 80 MPH, that running gear is changing direction 11 times a second.
He said it was a bit unnerving to look down at it out the cab. The mere thought of anything coming loose at that speed made your hair stand on end.