The Day the Gauge Changed


Yes, very interesting! I've always wondered why there was a half inch involved: 4 feet 8 & 1/2 inches, just seems strange to me! Someone has stated that the 4' 8.5" gauge was what the wagon wheels where set at. O.K.; but, still why?
 
Apparently the standard gauge for wagon wheels was the same for centuries. When the first railways were built to carry coal from the mines in northern England, they just put flanged wheels on coal carts and built tracks to fit them, so it was the rails that followed the vehicles, rather than the other way around.
 
I did not know that the Pennsy was originally 4' 9". And here I thought the video was going to be about the Delaware & Hudson, or Erie broad gauge to standard gauge conversions.

Yes, very interesting! I've always wondered why there was a half inch involved: 4 feet 8 & 1/2 inches, just seems strange to me! Someone has stated that the 4' 8.5" gauge was what the wagon wheels where set at. O.K.; but, still why?
The original gauge is really 4 feet 8 inches, but the British soon discovered that it caused problems when the wheels were the exact size of the track. The 1/2 inch is added so the fixed axle wheel can have some side-to-side play (which is also why they are sloped) and then cars can go around curves without binding. It was easier to move a rail than recast all the axles.

Here is a "greatly exaugurated for clarity" explanation of the sloped wheels, which is also really the reason for the extra 1/2 inch.
 
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I had never heard that the gauge of the track was opened up to 4'8 1/2' inch to loosen the fit between rail and wheel; but, it sure makes sense!
 
I had never heard that the gauge of the track was opened up to 4'8 1/2' inch to loosen the fit between rail and wheel; but, it sure makes sense!
Unfortunately, I cannot recall the source where I originally read that. I think it was in one of my engineering books, rather than a railroad book.
 
I know enough about engineering to know that there has to be clearance between the rails and wheels. I don't need a reference to any book about the subject, as it is easily understood as necessary.
 
I know enough about engineering to know that there has to be clearance between the rails and wheels. I don't need a reference to any book about the subject, as it is easily understood as necessary.
That was not directed at you, but rather a musing, as it has me now wondering where I first encountered the information. I often take notes, but even the notes get scattered about before I can organize and catalog them. I should just start putting a post-it right there in the text as I go, but even that would dictate knowing which book the post-it is in. :oops:
 
I certainly meant nothing by my statement either and I did not take your statement as being directed towards me! It was only stating what was obvious.
 



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