[time-nuts] Greek clocks - planets rather than seconds
Michael Wright talking about the Antikythera http://www.the-eg.com/videos/michael-wright-antikythera-resurrector-eg8 The video is 1/2 hour. I thought it was good. He's a colorful speaker. Anybody know how they made gears back then? Or machinery in general? What did they use for a file? How did they make files? The Computer History Museum is having an event: May 13, 2015 10:30 AM Secrets of the Antikythera Mechanism http://www.computerhistory.org/events/upcoming/ In 1900, sponge divers off the coast of the tiny Greek island of Antikythera made an astonishing discovery: the wreck of an ancient Roman ship lay 200 feet beneath the water, its dazzling cargo spread out over the ocean floor. Among the life-size statues and amphorae was an encrusted piece of metal, which after nearly a century of investigation, is finally revealing its secrets -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Greek clocks - planets rather than seconds
Hal, Gear wheels have been cut by hand for many a century. A simple dividing head made from wood and fixed to a mandrel would index a blank wheel and allow the teeth to be cut by a saw and then rounded up to a cycloidal shape with a file. As time progressed shaped files were used and later simple fly cutters with the cycloidal shape. Files were made by hand in a similar way as that are made today. Once the correct material was chosen, originally iron and later steel, a blank was shaped and the teeth cut using a chisel. The file would then be hardened by heating and quenching followed by straightening and warping before it set. As with most tasks machines either speed up the process or take the skill out of it. As an aside only use new files on brass until they have the edge taken off them then they can be used on harder materials. There is somewhat more to the above but it would take up too much bandwidth. Regards Peter On 11/05/2015 00:32, Hal Murray wrote: Michael Wright talking about the Antikythera http://www.the-eg.com/videos/michael-wright-antikythera-resurrector-eg8 The video is 1/2 hour. I thought it was good. He's a colorful speaker. Anybody know how they made gears back then? Or machinery in general? What did they use for a file? How did they make files? The Computer History Museum is having an event: May 13, 2015 10:30 AM Secrets of the Antikythera Mechanism http://www.computerhistory.org/events/upcoming/ In 1900, sponge divers off the coast of the tiny Greek island of Antikythera made an astonishing discovery: the wreck of an ancient Roman ship lay 200 feet beneath the water, its dazzling cargo spread out over the ocean floor. Among the life-size statues and amphorae was an encrusted piece of metal, which after nearly a century of investigation, is finally revealing its secrets ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Greek clocks - planets rather than seconds
Good question. I intrigued me so I researched it. To make gears the Greek craftsmen made a circular blank, then marked it out for the correct number of teeth, probably using dividers, then filed the teeth with a triangular needle file Analysis of the Antikythera Mechanism shows the sort of irregularities that this method would give, Michael Wright made gears this way to prove it. The teeth have a 60 degree angle and are triangular in profile, which is not very efficient, but good enough for a clock. I made a pair of gears this way, it took half a day but it worked. Thanks for the link. Tom Harris celephi...@gmail.com On 11 May 2015 at 10:32, Hal Murray hmur...@megapathdsl.net wrote: Michael Wright talking about the Antikythera http://www.the-eg.com/videos/michael-wright-antikythera-resurrector-eg8 The video is 1/2 hour. I thought it was good. He's a colorful speaker. Anybody know how they made gears back then? Or machinery in general? What did they use for a file? How did they make files? The Computer History Museum is having an event: May 13, 2015 10:30 AM Secrets of the Antikythera Mechanism http://www.computerhistory.org/events/upcoming/ In 1900, sponge divers off the coast of the tiny Greek island of Antikythera made an astonishing discovery: the wreck of an ancient Roman ship lay 200 feet beneath the water, its dazzling cargo spread out over the ocean floor. Among the life-size statues and amphorae was an encrusted piece of metal, which after nearly a century of investigation, is finally revealing its secrets -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
