koh303
26-Jul-2014, 10:12
I wish i had taken photos of the entire process, as to my (and everyone elses) detriment, there are NO online resources for taking these part, no photos, no manuals nothing. I would have thought someone would have posted stuff, but this is now my mission in life and my very next project, so stay tuned (if someone has a shutter they want to donate one for this purpose PM me).
This week i got this:
118951
When i tool the rear cell off the shutter, shutter leafs were flying out of the shutter, so i figured its a gonner, and what better a time then this to try and "fix" one of these... I am always scared of loosing a small bit of spring loaded something that will come flying out when i take it apart, but the truth is much less daunting, and the reality is, that it really is not that complicated.
Not a job for for those with no patience, or heavy fingers, and it does require lots of dexterity and persistance, but at the end of the day, its just like Lego's, albeit a bit small and more delicate... :)
I did find some old page with photos of an old copal shutter (which is installed in a TLR camera, and is very different then this type of shutter), but some of the basics are the same.
To start, removing the front cover and ring, is fairly easy, and so is the rear rings (aperture and preview). Then comes the tricky part.
The entire timing, shutter blades and release mechanism are mounted on one plate, and can be easily removed from the housing (4 screws on rear.
In this case, all blades were already apart, so i could not tell what of any was the correct orientation of the blades once they are back on.
Carefully putting them all back on the assembly i found there is only one way they fit on, and after 5-6 attempts i had them all lined up as they should be (i did have to repeat this at least twice later... read on for why). And then came the truly hard part. The aperture blades came falling out as i was about to put the shutter assembly back in the housing. I am no sure how or why this happened, but perhaps it is because the entire casing was loose and many screws were slightly loose allowing things to move around inside.
Assembling the aperture blades takes much more work then the shutter blades (there are 2 more blades and they are smaller and fit into a smaller guide hole). The aperture assembly is mounted on a separate plate. But once that was completed (after 5-6 attempts) i found that i did not know what orientation for the assembly plate inside the housing, and this took 2-3 times to figure out, and each time needed to assembly the blades as they would come out of position every time the plate came out of the housing.
Finally, i got the aperture blades correctly, and tested with the lever, and they did in fact work. I think there is a correct way to line these up, where each one is under the following blade, and this requires slightly flexing the last blade to go on, so that it slides underneath the first one.
With the aperture in place, the only thing left was to put in the shutter assembly. This has to be done "upside down" so that the shutter blades are resting on the assembly and the casing is lowered above it. There is a large guide pin here, to help align the assembly in the housing (not so with the aperture plate), so that went fairly easily, though i did loose the shutter blades 2 more times before getting everything in smoothly.
After 3 hours, i ended up with this:
118952
And - it lives! Shutter works flawlessly and is of the most accurate shutters i have seen, most likely due to it also being the newest one... All it cost was some finger print marks on the blades. Not a big deal considering.
The bad news is that no amount of work will fix the real problem of this lens :(
118953
So - does anyone have a rear cell for a Grandagon 75mm F4.5 they want to let go of? ;)
This week i got this:
118951
When i tool the rear cell off the shutter, shutter leafs were flying out of the shutter, so i figured its a gonner, and what better a time then this to try and "fix" one of these... I am always scared of loosing a small bit of spring loaded something that will come flying out when i take it apart, but the truth is much less daunting, and the reality is, that it really is not that complicated.
Not a job for for those with no patience, or heavy fingers, and it does require lots of dexterity and persistance, but at the end of the day, its just like Lego's, albeit a bit small and more delicate... :)
I did find some old page with photos of an old copal shutter (which is installed in a TLR camera, and is very different then this type of shutter), but some of the basics are the same.
To start, removing the front cover and ring, is fairly easy, and so is the rear rings (aperture and preview). Then comes the tricky part.
The entire timing, shutter blades and release mechanism are mounted on one plate, and can be easily removed from the housing (4 screws on rear.
In this case, all blades were already apart, so i could not tell what of any was the correct orientation of the blades once they are back on.
Carefully putting them all back on the assembly i found there is only one way they fit on, and after 5-6 attempts i had them all lined up as they should be (i did have to repeat this at least twice later... read on for why). And then came the truly hard part. The aperture blades came falling out as i was about to put the shutter assembly back in the housing. I am no sure how or why this happened, but perhaps it is because the entire casing was loose and many screws were slightly loose allowing things to move around inside.
Assembling the aperture blades takes much more work then the shutter blades (there are 2 more blades and they are smaller and fit into a smaller guide hole). The aperture assembly is mounted on a separate plate. But once that was completed (after 5-6 attempts) i found that i did not know what orientation for the assembly plate inside the housing, and this took 2-3 times to figure out, and each time needed to assembly the blades as they would come out of position every time the plate came out of the housing.
Finally, i got the aperture blades correctly, and tested with the lever, and they did in fact work. I think there is a correct way to line these up, where each one is under the following blade, and this requires slightly flexing the last blade to go on, so that it slides underneath the first one.
With the aperture in place, the only thing left was to put in the shutter assembly. This has to be done "upside down" so that the shutter blades are resting on the assembly and the casing is lowered above it. There is a large guide pin here, to help align the assembly in the housing (not so with the aperture plate), so that went fairly easily, though i did loose the shutter blades 2 more times before getting everything in smoothly.
After 3 hours, i ended up with this:
118952
And - it lives! Shutter works flawlessly and is of the most accurate shutters i have seen, most likely due to it also being the newest one... All it cost was some finger print marks on the blades. Not a big deal considering.
The bad news is that no amount of work will fix the real problem of this lens :(
118953
So - does anyone have a rear cell for a Grandagon 75mm F4.5 they want to let go of? ;)