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query re: locomotive weights

On 3/11/2011 8:01 PM Wolf K spake thus:

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You know, for a smart guy you're pretty dismissive of what most people rightfully see as at least a *potentially* dangerous threat to human health and safety. So far in this thread, I think Twibil's responses are the most reasonable in that regard. Seems to me as if you've drunk a bit too much of the nuclear industry's widely-circulating Kool-Aid on this subject.

Forget the too-often quoted-from Wikipedia. Here's a page from a much more credible source, HowStuffWorks, on DU:

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By the way, someone here, can't find just who, was correct when they wrote that DU is enriched uranium with the U-235 removed, leaving U-238. (More properly, it's the U-238 left over after the U-235 is removed in the enrichment process.)

Reply to
David Nebenzahl
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When I read a book about development of Boeing 747 I read there that they used depleted Uranium in that jetliner for counterweights for either ailerons or flaps (I don't recall which one)? I suppose they still do that and there are plenty of 747s flying around. :-)

Peteski

Reply to
Peter W.

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Both. The company was not too ethical. I ended up quiting it was so bad, but not before doing some whistle blowing to the customers.

Reply to
Lobby Dosser

Take a moment, draw a box (outline of your loco) and add in the points where the wheels contact the rail and the coupler. Now draw the relevant vectors of force, acting on the loco. This will be *gravity, *drawbar power. They will originate from the Center of Gravity. The gravity goes straight downwards, while the drawbar power intersects the drawbar center.

The result from adding the two vectors gives a combined one pointing to the rear and downward. You should have a diamond-shaped thingy with the resulting force vector being the longer diagonal line in the diamond.

Now, when you look at the resulting vector, it becomes obvious that the loco's front will lift from the rails once the resulting vector points /behind/ the rear wheels. It should also be obvious that the efective force on the wheels shifts quite a bit backwards compared to the gravity vector. But the axle height does not have any influence.

As a result, one could say, the lower the drawbar the better. Also, a loco being nose-heavy is likely ok, as long as it keeps pulling in the same direction. The resulting vector (above) will work out well.

Also, adding weight will increase pulling power, just draw the longer weight vector and update the diagram. The rear wheels should stall first ;-)

But on any loco that will run both directions or run inside a consist or train, it might be better to center the weight over the drivers ;-)

Have fun...

Reply to
Bernhard Agthe

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