The Antikythera Mechanism Episode 2 - The Main Solar Drive Wheel B1 -

The #AntikytheraMechanism Episode 2 - The Main Solar Drive Wheel B1, by Clickspring.

There are more than a few surprises hidden in the wreckage of this iconic part.

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Cameras used in this video:
Panasonic GH5 - https://amzn.to/2rEzhh2
Panasonic X920 - https://amzn.to/2wzxxdT

Tools & Shop Products:
"Solidworks 2013 Bible": http://amzn.to/2FObS1D
"Gears From The Greeks", Derek de Solla Price: http://amzn.to/2pii4ZD
"A Portable Cosmos: Revealing the Antikythera Mechanism, Scientific Wonder of the Ancient World" https://amzn.to/2NoLgIR
"Milling: A Complete Course (Workshop Practice Series)" - https://amzn.to/2K2QZ97
Hegner Scroll Saw: https://amzn.to/2IhteVW
Super Pike Saw Blades Size 4/0 pkg of 144: http://amzn.to/2IO6aPw
Dykem 80300 Steel Blue Layout Fluid, Brush-in-Cap (4oz): http://amzn.to/2HGPaJJ
Dormer A190202 Jobber Drill Set, 1.0 mm - 6.0 mm x 0.1 mm Size: https://amzn.to/2DR5fdb
Dormer A190203 Jobber Drill Set, 6.0 mm - 10.0 mm x 0.1 mm Size: https://amzn.to/2ITfeTa
YG1 NC Spotting Drill 8% Cobalt HSS 1/8 to 1/2" 120 Degree 5 Pc Set CNC Machine: https://amzn.to/2G7ylv6
Blue Matador Abrasive Paper - https://amzn.to/2IAFiBT

Abbreviated Transcript:

00:59 This part was fabricated, not cut from sheet stock. And once that fact sinks in, a whole bunch of questions arise. For example: What were the tools available to the original maker to form this part? We know for sure about some them, like dividers, hammers and files. But were there others tools we don't yet know about. And what about the dovetail join itself?
02:09 But whatever the reason, it must have been a very good one, because this is by no means the easy way to make this part. As per the original device, the cross members will be notched, drilled and then riveted together, and the dovetail joins will be filed to shape,
03:14 The slightest misalignment, and the other intersections become compromised. More metal than necessary would be removed, with the result being a poor overall fit. So I'm going to use a simple circular jig to make life a bit easier. I used the mill to clean up the raw cuts and also to drop in a reference hole
06:14 The process of riveting has drawn the 2 parts tightly together, leaving the rivets just above the surrounding metal surface. From here I can use files and abrasive paper to take them all of the way down to that surface, and then blend them into the surrounding metal.
07:38 With so much precision hand work, how did the original maker solve the problem of workholding? There's no doubt that a secure method of holding the work would have been essential. So what was the ancient equivalent to this modern screw vise? Filing small parts doesn't usually require a whole lot of force.
08:02 So I imagine a simple wooden clamping peg like this, could easily do the job, not unlike a modern pin vise. A clamping ring, designed to be a sliding fit over the tapered section, could be gently tapped into place to provide the clamping force.
08:19 I think it'd do a great job, and its consistent with the known technology of the time. Of course a lot of the detail of workholding devices like this will probably never be known for certain. But the mechanism has many features that strongly suggest a tool technology that goes well beyond files and hammers.
10:09 The part was then mounted on the lathe and taken to final dimension, all ready to receive some of those amazing triangular teeth. Now there's a lot I'd like to talk about regarding the geometry and formation of those teeth, so rather than make this video too long, I'll save that discussion for a later time.
10:31 But after completing the first substantial piece of the mechanism, its becoming clear to me, that the story of how this machine was made is going to be as much about the tool technology used to make it, as it will be about the device itself.

References:

Gears From The Greeks - Derek de Solla Price: http://amzn.to/2pii4ZD

The CT and PTM data that the AMRP have made publicly available can be found here: http://www.antikythera-mechanism.gr/data

Gear schematic can be found in Tony Freeth's 2012 research paper:
http://dlib.nyu.edu/awdl/isaw/isaw-pa...

Credits:

Clips from "The 2000 Year Old Computer" courtesy Images First Ltd.

The Antikythera Mechanism Episode 2 - The Main Solar Drive Wheel B1, by Clickspring.