Transplanting Bolex EBM 170º Shutter to SBM
Hey there! I recently purchased a Bolex SBM and have been loving it so far. The one thing I'd love to change though is the shutter angle—the built in variable shutter is 135° at its most open setting, and thus the motion rendition is a bit choppy compared to the 180° standard I'm used to on an SR3/XTR.
After doing some research I noticed that the electronic Bolexes (EBM and EL), as well as possibly some early non-reflex models, have fixed 170° shutters. I'm wondering if its theoretically possible to transplant a 170° shutter into a Bolex that came with the variable 135° shutter. I don't expect to keep any variable shutter capability—obviously it would be a permanent change over to the fixed 170° version.
The main limitation I'm concerned about is that a 170° shutter doesnt provide enough cover for the SBM's pulldown mechanism to complete the frame advance, and that the EBM/EL have a faster pulldown which makes a 170° opening possible.
But if it was a visual aesthetic decision rather than mechanical decision (perhaps Bolex thought the tighter shutter would be better for most users since there would be less motion blur), perhaps it's possible. Unfortunately I don't have the means to test this myself, so I'm wondering if any Bolex experts/machinists can chime in!
(Sorry for the incomplete topic name, it got cut off by the forum software!)
Edited by Gus Bendinelli, 10 June 2018 - 09:32 PM.