Contaflex Super: shutter stays open during exposure cycle

[Theo Sulphate]

I'm trying to diagnose what seems to be an odd issue: at all speeds, but specifically the slower ones, I can hear the shutter and delay timing running, but the shutter blades remain fully open during the complete operational cycle.

Being that the Contaflex Super is one of those leaf-shutter SLRs, the operational cycle is:

1. Winding the film cocks the shutter, lowers the rear film baffle, lowers the mirror, and opens the shutter.

2. Reflex viewing can now be done through the open shutter. Adjusting the aperture opens and closes the aperture blades.

3. Pressing the shutter release closes the shutter, raises the mirror, raises the rear baffle, and then the shutter opens and closes for the proper exposure time. Restart again at step 1.

Since I can hear the shutter operating, such as the 1-second delay timing, it seems the mechanism itself isn't stuck. It's a Synchro-Compur, so the circular blade-ring, on which all the blades pivot, should be moving. If the blades are stuck down, the ring wouldn't move and I wouldn't hear the gear train, would I?

These types of leaf shutter SLRs are not easy to work on and the Contaflex Super is notorious, on the web at least, for having "one way paths" that can make disassembly a disaster.

I don't know how far I can go with this one. Is there anyone who can and will work on them?

 

[lobitar]

Hello. Most likely trace amounts of oil on the shutterblades somewhere. Personally I woundn't think it worth the expense and trouble to have i repaired. Don't you think it would be better to locate another one? That is if your specimen has no 'empathy-value' for you.
(Just yesterday I was lucky enough to find a very clean-working sample on a flea-market here in Copenhagen). Good luck - the Super reportedly is the most common model with abt 135.000 pcs produced.

 

[shutterfinger]

http://www.suaudeau.eu/memo/rep/Compur-shutter-repair-manual.html Compur Repair Manual lists the shutter as CN-1110-024. http://www.suaudeau.eu/memo/rep/compur-repair/03-22.html
This shutter is a variant of the CN-1110-000. http://www.suaudeau.eu/memo/rep/compur-repair/04-18.html
The shutter needs a Complete CLA as some lever is sticking causing the problem(s).
NO I am not interested in servicing it although I've serviced some CN-1110-000 shutters with success.
Go to your local Home Depot and get a can of CRC Quick Dry Contact Cleaner

Remove the lens cells and flush the shutter out and operate it while wet with the cleaner, it might get you some extra operating time before the tear down is an absolute necessity.

 

[Theo Sulphate]

...
The shutter needs a Complete CLA as some lever is sticking causing the problem(s).
...

Thank you for the reply and the links. I'll try what you suggest, but will plan for a complete disassembly and CLA.