[STATUS] - July 2018 (Update July 30th, 7:15pm AEST)

(Update July 30th, 7:15pm AEST)

The pin and slot mechanism in progress (short movie) - The pin moves from one end of the slot to the other throughout the full rotation. This effectively superimposes a quasi sinusoidal variation upon the mean sidereal rate of the moon, and was the ancient Greek way of modeling the slight rate variation that we now know to be due to its elliptical orbit. The amount of offset of the slot wheel pivot (approx 1mm) was selected by the Maker to give the closest approximation of the observed lunar motion. This slight variation to the rate of the lunar output pointer would have been barely detectable by the casual observer.

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(Update July 28th, 7:15pm AEST)

Depthing and planting the pin and slot gearing.

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(Update July 27th, 8:00pm AEST)

The offset pivot that is critical to the operation of the pin and slot mechanism of the lunar orbit gearing - much like the retaining lugs, its right at the lower limit of what I can realistically hold in the small parts vise to work on with a file.

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(Update July 24th, 7:30pm AEST)

2/3rds of the coaxial E assemblies - the remaining third is the E platform (E3/E4) from the previous video, which is the outermost of the 3 assemblies in the stack - remarkable stuff.

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(Update July 23rd, 4:30pm AEST)

The E inner arbor in progress - This is the central component of 3 coaxial rotating assemblies that are critical to the operation of the lunar orbit gear train.

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(Update July 21st, 10:30am AEST)

(Short Video) A close up look from the side at how metal deforms and flows during peening - the overhang at the start was approx 0.5mm

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(Update July 19th, 6:30pm AEST)

The outer hub of the coaxial drive assembly that feeds into the lunar phase gearing - its an absurdly small part to be working on today, let alone 2000+ years ago. Of the shapes the maker could have selected for the E5 drive boss (that would have been much easier to mark out), a beautiful little pentagon was chosen.

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(Update July 17th, 8:40am AEST)

AM speculation: Somewhere on the ancient bench, was a collection of small rods and discs that had these general characteristics - very simple and effective alignment tools that ensure concentricity and support of the parts during riveting.

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(Update July 14th, 8:00pm AEST)

Going the full peen to retain D1 on the D assembly arbor - The short cylinder helps keep the arbor upright for the process. The peened area was sanded off a few moments later to give a flush surface that sits just underneath the bridge plate.

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Much filing of teeth over the last week, and I'm now moving on to making some of the assemblies for AM Ep 8 - Here are a few pics from today. The C assembly is a 3 part composite with a very cool little notch to permit entry of the retaining pin on assembly - its a tight squeeze! The alignment jig keeps everything where it needs to be, and the drill is again working well freehand without the driving mechanism. 4 rivets in total (2 through the lower wheel and plate, 2 through the whole assembly) pull the whole thing together. Its a most unusual little assembly, and the recessed retaining pin idea again makes it clear that The Maker was actively pursuing miniaturization. It still blows me away every time I make parts for this machine, just how small everything is - this assembly is not much bigger than my thumbnail.