Bronica SQ-A: Shutter won't open when cocking

[yotanb]

hi!

I got ahold of a bronica sq-a – something's not quite working, though. hopefully I can figure it out with your help.

for the purposes of testing I put the camera into multiple exposure mode. also I'm using a brand new battery.

the problem:
I can use the crank to cock the shutter and then release it no problem. except when cocking, the shutter blades don't open as expected – hence the viewfinder remains black. you can see the blades move ever so slightly, but that's it.

EDIT:
looks like when I put the camera away for a while and then try again, the shutter opens a little at the first try.

any ideas what might be causing this and if it's fixable?
thanks a lot in advance!

 

[wiltw]

There is an arm on the body, that engages an arm on the back of the lens, to cock the shutter ordinarily. If you are in multiexposure mode, the shutter should open with the second stroke of the speed grip,, or at the second half of the crank of the film winder (without speed grip).

Have you attempted to remove the lens from the body? If the shutter is not cocked, you should not be able to remove the lens from the body.

 

[reddesert]

If you can cock the shutter and then remove the lens from the body, you can then test the lens and body independently. It seems more likely to be a lens problem. If you can remove the lens in the cocked state, the pins on the rear of the lens will be at the green colored dots at one end of their arc (cocked position), same for the pins on the body. You can then fire the body and wind it again to watch the cocking pins move.

On the lens, there is a way to uncock (close) it by pressing a little lever hidden under one of the lens bayonet flanges. Holding that lever in, you can then move the rear cocking pins easily with your finger to see the shutter open and close.

All of these actions should move easily so don't force anything.

 

[yotanb]

with the lens detached, the shutter seems to open slightly now. – see video: https://www.dropbox.com/s/iya2473by1a57vr/IMG_7348.mov?dl=0
it also looks like there is oil(?) on the shutter leaves. could that be the problem?

 

[reddesert]

I can't tell if you're pushing the little lever behind the bayonet flange when you "uncock" (close) the shutter,moving the pins away from the green dot. You should only be able to uncock it while pushing the little lever. If you then let go of the little lever, and cock the shutter by moving the pins to the green dot, you should feel a moderate resistance from the shutter spring, and the leaves should spring open instantly as you cock it. In the movie you posted where the leaves don't spring open instantly, it certainly seems like there is something wrong - maybe it is oil on the blades. A shutter service / cleaning is likely required.