Prontor-S Aperture Blades

[jharr]

I had a bad Prontor-S shutter on my Isolette III, so I decided it wouldn't be any less useful if I tried to take it apart and 'fix' it. So I got it apart and thought I was documenting the disassembly adequately with my phone camera, but I missed the subtlety of the aperture blades. They all look the same when they are 'together', but once I got them apart and cleaned (they were totally stuck together), it appears that there are 4 different kinds/shapes in there and I have no idea which ones go where.

4 of these:


3 of these:


2 of these:


1 of these:


If anyone has advice or a link that will show me how to reassemble these in order, that would be greatly appreciated!

James

 

[02Pilot]

I wish I could help. I have a copy of a Prontor repair manual, but it's for later versions. The manual simply says "Whereas former PRONTOR-SVS shutters had ten diaphragm blades, the number of blades has been reduced in the new shutters...." These newer models appear to have all the blades of identical design, and there's no information about the older models.

If it were me, I'd probably start trying different combinations until I found an arrangement that worked smoothly, then button it up and call it done. Not strictly the right way perhaps, but likely good enough for government work.

 

[shutterfinger]

I just did a google search for Prontor Service Manual and got copies of Prontor service manuals in PDF. The shutter you have is a variant of the base shutter.
Aperture blades attach to the controller plate in a counterclockwise direction. All 4 of you blades have a flat on one end. Some have the notch in a different position. The flat end most likely goes to the outer edge of the controller. The notches and flat edges will go in a position where the notch prevents the blade from contacting the pin of an adjoining blade and the flat(s) where the blade would otherwise contact parts in the shutter or the shutter case.

 

[Tom1956]

I've mixed up blades before. You can get it right if you keep experimenting.