Rumor has it that 4’8 1/2” was the measurement between the wheels of a Roman chariot. Supposedly that became the “standard” wheel distance. I repeat rumor. I have never attempted to prove or disprove this rumor/ theory.Exactly why 4' 8 1/2 inches instead of something nice and even like 5' I cannot answer. I do not feel like doing all the calculations to find where the theoretical ideal would be. I'm guessing it is close. Plus with today's materials (steel vs iron etc.) it would be a different answer than it was back when the standard was set.
Unfortunately, no scientific reason really, but this seems to be why.I would prefer that there was some scientific explanation for why 4' 8.5" became the standard and not the width of a wagon's wheels. Maybe someone has an explanation?
Interesting. Pitty that back then no one sat down to do the math. Speaking from an engineering perspective, there is an optimum gauge that would take into account the equipment weight/friction vs load capacity, vs rail construction, and all that vs cost. Varibles to be optimized would be the construction materials, axle weight, bearing load, wear coefficients, truck/wheel mounting complexity, etc. I believe I stated earlier given modern building materials and alloys, an engineered gauge would be different today than it was back in the day when the standard was set.Unfortunately, no scientific reason really, but this seems to be why.
WHEN Stephenson was building the Stockton to Darlington railway, he decided on the gauge by measuring the axle width of 100 farm wagons and taking the average, the result being 4ft 8 in. He may have intended to allow local people to use the track to convey goods with their own wagons.
I would say you are probably safe in that bet.I am going to give odds that I am the only person here (toot, toot) to have ridden - locomotive and combine - the READER RR in SW Arkansas.
I think it was more to do with expediency and cost, there's little to differentiate between a cart and a freight car, it's just a box on wheels, at the time wheelwrights had plenty of experience in building carts, wooden wheels already had metal rim's, so why not simply adapt what you already have in plenty, cost would be minimal, a new hitch, and flanged rims, strengthened sides and it's ready to roll.Interesting. Pitty that back then no one sat down to do the math. Speaking from an engineering perspective, there is an optimum gauge that would take into account the equipment weight/friction vs load capacity, vs rail construction, and all that vs cost. Varibles to be optimized would be the construction materials, axle weight, bearing load, wear coefficients, truck/wheel mounting complexity, etc. I believe I stated earlier given modern building materials and alloys, an engineered gauge would be different today than it was back in the day when the standard was set.
I don't think that was the ideaInteresting. Pitty that back then no one sat down to do the math. Speaking from an engineering perspective, there is an optimum gauge that would take into account the equipment weight/friction vs load capacity, vs rail construction, and all that vs cost. Varibles to be optimized would be the construction materials, axle weight, bearing load, wear coefficients, truck/wheel mounting complexity, etc. I believe I stated earlier given modern building materials and alloys, an engineered gauge would be different today than it was back in the day when the standard was set.
You have to love the old tank engines, workhorse of the railways.Yep - Puffing Billy in Victoria Australia.
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