I am the winner of the eBay Auction: 7630863409
Which was for the newer style Bolex underwater housing for my EL - I picked it up in good condition but it did not come with the follow focus and aperture gears to attach to the 10mm and 26mm lenses that the housing supports...
At the moment I only have the 10mm non-preset lens and will possibly have access to a 26mm preset to use from a colleague (or at least he will want to use the housing with his EL )
The 10mm RX Switar lens has 'splined' or longitudinally ribbed (I forget the right term) focus and aperture rings each with an outside diameter of 37mm.
Inside the housing the focus gear is approx ~48mm in OD with 46 teeth and the aperture gear is approx ~30mm in OD and has 28 teeth. These can be seen in the 3rd photo from the eBay auction.
From the distances between the centers of the lens and each of these gears I can figure out the correct diameter and number of teeth required in each ring required for the lens. I am yet to do this but was wondering if anyone knew the exact figures in any case ?
the next question which is really the biggy for me is:
How are the gears made to be easily removable from the lens ?
I have access to both a mill and lathe and will use that hard self-lubricating plastic stuff you find in all sorts of places to fabricate the gears themselves
I was thinking of a simple push fit in which the splined/ribbed rings would help provide the correct resistance for the gears i.e. easy to push on but hard to turn against. One thing I can think of is that this would not be the ideal solution is that the push-fit of the inside diameter would wear over time...
Is this the best way to go about this ? is there a better quick release system around ? I'm sure there are plenty of designs for follow focus systems... Bearing in mind I'm stuck with the aforementioned gears already
Any help appreciated !
Edited by Nick Mulder, 07 August 2006 - 04:52 PM.