Posted on 12/10/2007 12:32:15 PM PST by Dean Baker
Whoops! Sorry about that...Make it "Troy" then?
The joinery on a solid wheel is as problematic I would think — are you sure that a cart used day in and day out in that period would have solid pieces joined together, rather than spokes? A rarely used cart, maybe. But one used everyday for miles and miles in hilly rocky territory — my guess is it would have spokes. Spoked wheels were around maybe 2000 years by then, and a foot paddle operated lathe is no greater complexity than a spinning wheel, which as I understand was a common item. That is to say surely there were many lathes and not costly at all.
The development of the axle is much more interesting. When did the wheel bearing come about and how was it lubricated?
The spokeshave was intended to make spokes without the lathe.
Ancient representations of Greek chariots of the Trojan War invariably show them with spoked wheels, as did Egyptian pictures. Chariots were, had to be, light if they were to fulfill their mission of mobility. OTOH, they were also most definitely a weapon of the aristocracy.
I believe there is evidence of spoked chariot wheels back about 2000 BC.
Both Joseph and Jesus were carpenters...
More like rolling pins.
And how long was it before the first mullet bearing red-neck put wood shavings in the crank-shaft and charged for a new one, to rip-off unsuspecting yuppies??
Some of the early bearings were lead ( or babbitt, an alloy) and were poured in place around a greased axle.
The grease was used to keep the lead from sticking to the axle shaft.
When they wear out they are re-poured. They wear quite well is slow rpm applications.
The chariot had very advanced wheel bearings, and advanced wheels. The oxcart was also an advance over what came before it, which was a stick dragged by an ox, which had no wheels and therefore no problem with wheel bearing lubrication.
Boy, did I fall for that, LOL.
Years ago, the Smithsonian postulated that the Egyptian pyramids were built much more rapidly and with far less manpower by using eight wooden bowstring arches held together with pins to turn the square blocks into a thick axle with two “wheels”. Like if you put two rubber tires on the ends of a rectangular block.
Then all they had to do was make a dirt ramp, a very old technology, around the pyramid and roll the blocks up it. Finally, when the capstone was emplaced, remove the dirt and you have a fully formed pyramid.
Now we see the truly knowledgable posting in.
The wheel was known early on, but the truly brilliant break through was the axle and bearings.
Spoked wheels have the ability to be “trued”.
Solid wheels warp and are simply discarded.
Do you have any link to what type bearings they used? Or can you describe what they were? Thanks.
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