You talking about one of these? (See attachment)
John Degnan [email protected] [email protected] ----- Original Message ----- From: Pete To: [email protected] Sent: Thursday, October 25, 2012 12:34 AM Subject: Re: {S-Scale List} Prototype Version of a Clearance Gage The attach picture to this topic is a clearance measuring car for acurately measuring fixed objects along the track,ie tunnels, through bridges narrow rock cuts. It has arms that are attached to a fixed frame mounted on the centerline of the car, they are extended out to the standard width of that particluar section or route of the RR. Then as the train moves along slowly and the arms strike a fixed object they would fold back till they cleared the obstruction. At the end of each object,ie tunnel or bridge each arm that has moved is measured and recorded, then in the office a diagram could be made showing the cross section clearances for the route. Today we use a laser mounted on the geometry car that measures clearances, track centers and track conditions. Pete Silcox, retired civil engineer from CSX Engineering Dept.
