I understand the need for having the exact, or nearly the exact same part, to replicate a prop identically, but there must be a 3D model with almost exact characteristics that somebody has modelled. I hope it is found, but as years pass, it will be more and more difficult to find this gear, if that hasn't been demonstrated at the present time which is almost 45 years later.
I have faith. We keep ID'ing stuff all the time. What was it, a year ago, that tubachris ID'ed the thermostat for the Snowtrooper? A couple years before that that we not only ID'ed the Veyron model airplane engine parts used on Han's blaster (as well as all over the frikkin' place in ANH), but that the original parts from the original moulds were still available to purchase from the son of the original maker. It's possible this won't ever be nailed down, but that doesn't make the attempt foolish or doomed to failure.
Now... Does anyone have a line on what sorts of water pumps were around in the mid-'70s in the UK for koi ponds?
Have you tried looking at the EMA model supplies catalogues? There's gear cogs in there which look the same and they definitely used some of their products, the model makers used EMA quite extensively and this obviously bled through in some areas, the Boba Fett costume appears to be littered with them for example.
The really great thing with EMA is that thier product remains virtually unchanged.
Still trying to figure out what real world part they used in 1975 for the chestbox gear. 2” diameter, 18 teeth, white plastic. I’ve looked at printers, copiers, models, RC cars, oil pumps..you name it. Still can’t figure it out!
That's what I've been banging my head against, with nothing to show yet. The two directions of enquiry I've been following have been:
• Pump internals of some kind that Ainsworth had on hand from one of his main product lines.
• Pieces some of the Elstree wardrobe people had from one of their drift-net runs through the local electronics supply shop down the street (where all the switches and switch covers and switch bay covers and panel lights and so forth came from).
Do we know who did the actual deco? We have the pic of someone modeling the one complete ensemble (over a white tank top) with a pile of helmets next to him. Was that at Ainsworth's shop, or on the lot?
For me I think it all lies in the teeth of the gear. It's extremely specific.
Is it a gear made to turn another gear with the same teeth?
Is it a sprocket made to move something such as a chain, conveyor material, film, etc...?
Is there a pivoting cam that sits between the teeth and the movement of the gear or the movement of the cam is why the gear teeth looks like it does?
I feel like we need to send photos of the part to people who could at least tell us what it's designed to do, that would narrow down the search.
So why does a sprocket have tapered teeth? Maybe because the teeth need to reliably feed into something instead of move another wheel in the same plane of movement? Ot maybe to transport something like a chain or maybe film?