Practika L3, 50 mm lens aperture stuck open.

[Luddite Frank]

I have a lovely Practika L3 SLR with a 50mm f:1.8 automatic lens.

The aperture leaves in the lens seem to be stuck open. They do not respond either the Manual / Automatic knob, aperture ring, or the little pop-out pin that responds to the actuating plate right behind the lens mount.

Is this common with Practika lenses and is there a simple DIY fix?

I am assuming this was caused by focusing lube migrating to the aperture section.

The rear of the lens has a wide ring with three screws through it;
I'm tempted to try opening this thing-up and seeing if I can free the aperture....

Or would I be better-off finding an operable lens or sending this one out for CLA ?

😕

 

[Sarcophilus Harrisii]

I doubt it would be worth getting serviced as they are available cheaply. Yes, I suspect that unless a mechanical failure has occurred your problem would be some helicoid grease or evaporations from this contaminating the aperture blades. Given the affordable cost of the lens and the expense of having it professionally attended to I'd suggest you have little to lose by trying to clean it. It may help to see some images of the lens in question to be able to offer more specific suggestions. I may even have an example of it myself depending on the version it is. I would not anticipate any major problems reaching the aperture blades from either the front, rear, or both, though. Gentle swabbing with a minimum of lighter fluid should get them going again, unless, of course a linkage or other mechanical problem has occurred, but this may well be fixable anyway.
Cheers
Brett