I have a Rodenstock Ysarex 127mm f4.7 in a Prontor SVS shutter. I want to remove the lens rear and front cells (glasses) from the shutter. I was able to unscrew the rear cell, but I have no clue how to unscrew the front cell. No threads visible, no notches, no screws... I tried unscrewing it using pressure with my fingers but it doesn't move.
I'm tempted to leave mine alone as it works fine at all speeds except half and one second but I'm still interested in learning how it comes apart as I couldn't work it out myself.
I've done it the hard way... Drilled two holes in the black rim edge to allow clearance for a spanner. It came off easily. The two holes can be painted with black enamel and you won't notice too much.