SeattleRailFan's video: Railgrinder working the rails in Marysville WA 1-29-2014

I was in Marysville, a small town about 35 miles north of Seattle. I left the freeway and was headed over to State St which parallels the BNSF mainline. As I turned south onto State St, I looked down the mainline and saw some sort of a MOW (Maintenance Of Way) vehicle farther down the track. As I got closer I realized it was a railgrinder machine working the track, headed northbound. This was very exciting! It was my first time seeing one, as they aren't all that common. I quickly found a place to make a U-turn so I was also headed north. I got caught at a stoplight and shot a bit of video as they were working the 88th St crossing. I really wanted to get ahead of them so I could get a clear shot. This isn't as easy as it sounds as there are many businesses in between State St and the railroad tracks. I knew there was a Subway sandwich shop just ahead where I could drive around to the back and get next to the tracks. I arrived just as they were working a road crossing and shot some good video of the machine in action. It was raining, so I stayed in the car and shot through the windshield. You can see the crew working the machine back and forth, grinding the rail at a small private road crossing. The sparks from the grinding wheels are visible under the rubber shields on the sides of the machine. ================= What is a railgrinder, you ask? It is used to restore the correct profile to the top of the rail. The top of the rail, where the train wheels run, is not flat but has a slight curve to it with a radius on the edges. This profile, in concert with a specified profile on the train wheels, works to help minimize friction and keep the wheels from hunting side to side as they roll. Proper rail and wheel profiles saves fuel. As trains roll over the rail, the rail wears and the rail profile changes. Train wheels locking up under braking, flatspotted wheels and such also take their toll. Part of regular track maintenance is to use a railgrinder to restore the rail profile back to specifications. Underneath the shields on the sides of the machine are several rotating grinding wheels. Each is angled at a different angle to produce the correct rail profile. There are different styles of railgrinders. Mainline railgrinders consist of several cars hooked together. Each car may have a dozen or so grinding wheels on each rail. This allows them to make multiple passes over the rail all at once. What you see in the video is "Switch and Crossing" railgrinder. They use smaller grinding wheels to get into the closer tolerances found around switches and road crossings. When a mainline railgrinder approaches a switch or crossing, it lifts the grinders off the rail as it passes the switch or crossing then lowers them back onto the rail after it clears. A Switch and Crossing grinder is then used to grind the rail near switches and crossings.