Against All Odds

Does anybody out there recall the "Toonerville Trolley" cartoon?

quote:

Does anybody out there recall the "Toonerville Trolley" cartoon?

Great analogy. I'll be trying to remember the streetcar operator's name all week.
Phil

The Skipper.

Another long telephoto lens shot, which for-shortens everything in the scene, making the track look much worse than it really is.

There is absolutely nothing wrong with that track. I have run on MUCH worse.

As Hot Water said, the long lense greatly exaggerates the flaws in the track. This is really no big deal.

Rich, Overall, didn't 6 or 8-coupled steam locos require a higher standard of track maintenence than diesels?

quote:

Originally posted by Kent Loudon:
Rich, Overall, didn't 6 or 8-coupled steam locos require a higher standard of track maintenence than diesels?

Not necessarily.

How hard a given locomotive (or car) will be on the track is determined by how much weight per axle it carries. That is called its "axle loading."

The axle loadings on the 765 are around 64,000 pounds per axle. An SD40-2 that weighs 399,900 pounds (a mid-range weight for that model) has axle loadings of 66,650 pounds. A 4-axle GP9 weighs about 250,000 pounds. Over 4 axles that is 62,500 pounds per axle. A 4-axle, 286,000 pound freight car (also a very common weight) has axle loadings of 71,500 pounds! Believe it or not, that heavy box car will stress the track much more than the 765 would.

This is why the older 6-axle power (SD7's and SD9's) were used so often on light-duty branch lines. They weighed just slightly more than the 4-axle GP models, but spread that weight over 6 axles. A typical SD9 had axle loadings in the 50,000 pound range.

Thanks, Rich,

However, isn't it true that most railroads have "tightened" the track gauge on curves, so that steam power can longer maintain the speeds possible "back in the day"?

Actually it's the opposite.

The rail gauge on curves is slightly widened. This is to accomodate the wheel base of long trucks and steam locomotive driver sets. The tighter the curve, the wider that spread, up to a limit of course.

There is a chart for this in one of my B&O Maintenance of Way books. It also tells how much of a gap must be made at a bolted rail joint, depending on the ambient temperature when the joint is made fast. The B&O also used rail thermometers that had two scales. One was for the temperature, the other showed the rail gap size required.

Ed Bommer

quote:

Originally posted by Kent Loudon:
...isn't it true that most railroads have "tightened" the track gauge on curves, so that steam power can longer maintain the speeds possible "back in the day"?

No...where did you get that idea?

One factor that has slowed speed on curves is the gradual reduction in superelevation on routes no longer having regularly scheduled passenger trains. However, there was always some variation there, as some roads had their own standards for superelevation. My home road uses less superelevation than it did in the 1940's, but I can't say how the gauge compares to the 1940's on curves.

In my railroad experience, the only time we had concerns about steam engines and curves was on auxiliary tracks, especially wyes, and that was because of poor tie condition (which would affect gauge if the outside rail rolled some due to the inability of the ties to hold spikes tightly).