Can anybody answer this for me??

[mudchicken]

Jeremy:
Ed "whirls" really good! Add to that the fact that the gap in a normal frog takes a heckuva beating with every wheel that passes over it. You might liken the gap in a frog where the wheel passes over the rail to a highway pothole, except no street could survive that type of beating. On main lines, railroads are going back to using "spring" frogs where the gap is closed except when trains go off the main track. (Spring frogs have their own set of related headaches). Without a spring frog on a busy main track, you will see welders constantly adding metal to the frog to build it back up and tampers (Big yellow machines) pushing rock back under the ties to eliminate dips in the track and allow trains to operate at full speed.

Also, railroaders call the rocking phenomena ("rock and roll", a term coined in the 1910's!) which is at its worst between 8 and 17 mph, where a wheel on a freight car can actually lift off the rail caused by harmonic rocking of the cars. When you see trackmen walking around on the track with a funny looking bright metallic bar and stooping over every so often on the track., they are looking for cross-level or dips in the track that should not be there (that start the cars rocking) ...

Please, as Ed says, stay away from the track and watch from a distance.

-mudchicken

[AltonFan]

I recall watching a video of a steam era C&NW freight train going by, and noticing that the cars, especially the tender did an awful lot of swaying.

[AltonFan]

I recall watching a video of a steam era C&NW freight train going by, and noticing that the cars, especially the tender did an awful lot of swaying.

[edblysard]

Hi Jermey,
I will give it a whirl.
Know what a track frog is?
Its the point where the two rails meet, a very heavy guide ways for the wheel flange to follow.
Because it is such a heavy and stouter piece of track work, and because of the way turnouts have to operate, the support under a frog is greater and more spread out than the support under the opposing rail.
Bet the train sways out, away from the center or other track first.
The frog has no "give" in it like the rail does, no ability to flex, its almost like a bump in the track.
If the track work leading up to and away from the frog isnt kept maintained well, the force of running over the frog shifts the weight of the cars and locomotive to the outside rail, which tends to have more flex.
Over time, the outside rail will begin to settle deeper into the ballest, and the problem becomes even more pronounced.
Imagine driving a car, and you run over a bump in the road, but the bump is only on one side, say the passenger side of the car.
The passenger side rises up, and the drivers side will sink down, due to the action of the suspension, springs and shock asorbers.
Same thing with the locomotive and cars, the swaying is the result of the suspension system trying to compensate for the bump, or high spot in the rail.
Sometimes it can get so bad you would swear the car is going to tip over!
Try having to stand inbetween two opposing trains on double main, both running over the frogs on their track, and watching the cars, it looks like they are going to smack into each other at times.

On second though, do not try that at all, I get paid to take that risk, you dont, and shouldnt
In fact, if you dont railroad for a living, I suggest you stay at least 50' back from the track.
Cars have banged into each other that way.
Stay Frosty,
Ed

[edblysard]

Hi Jermey,
I will give it a whirl.
Know what a track frog is?
Its the point where the two rails meet, a very heavy guide ways for the wheel flange to follow.
Because it is such a heavy and stouter piece of track work, and because of the way turnouts have to operate, the support under a frog is greater and more spread out than the support under the opposing rail.
Bet the train sways out, away from the center or other track first.
The frog has no "give" in it like the rail does, no ability to flex, its almost like a bump in the track.
If the track work leading up to and away from the frog isnt kept maintained well, the force of running over the frog shifts the weight of the cars and locomotive to the outside rail, which tends to have more flex.
Over time, the outside rail will begin to settle deeper into the ballest, and the problem becomes even more pronounced.
Imagine driving a car, and you run over a bump in the road, but the bump is only on one side, say the passenger side of the car.
The passenger side rises up, and the drivers side will sink down, due to the action of the suspension, springs and shock asorbers.
Same thing with the locomotive and cars, the swaying is the result of the suspension system trying to compensate for the bump, or high spot in the rail.
Sometimes it can get so bad you would swear the car is going to tip over!
Try having to stand inbetween two opposing trains on double main, both running over the frogs on their track, and watching the cars, it looks like they are going to smack into each other at times.

On second though, do not try that at all, I get paid to take that risk, you dont, and shouldnt
In fact, if you dont railroad for a living, I suggest you stay at least 50' back from the track.
Cars have banged into each other that way.
Stay Frosty,
Ed

[JeremyB]

Hi Everyone

When I go railfanning I notice all the time that when the train passes over a switch it rocks back and forth quite alot,what causes this? and does it happen alot because it can get a little scary watching all those freight cars and loco's sway back and forth.

thanks and I hope that somebody can answer this.

Jeremy

[JeremyB]

Hi Everyone

When I go railfanning I notice all the time that when the train passes over a switch it rocks back and forth quite alot,what causes this? and does it happen alot because it can get a little scary watching all those freight cars and loco's sway back and forth.

thanks and I hope that somebody can answer this.

Jeremy