Miranda D - f:1.9/50 - stuck aperture?

[Luddite Frank]

I just picked-up a slightly frowsy but functional Miranda D, to complete a kit in a Miranda "attaché" system case.

Lens is Miranda (Soligor) 1:1,9 f=5cm, with the shutter-release linked stop-down.

The aperture seems to be stuck open, and the flat pin protruding from the back of the lens mount seems frozen....

Is this is common issue with this lens?

Any DIY fixes?

Thanks,

LF

 

[Luddite Frank]

So, I treated the lens to a ride in the oven at 100* F for an hour or so, and I got the diaphragm to move, slowly.

Helical lube had migrated to the aperture leaves.

Any suggestions / tutorials for opening this lens to get at both sides of the diaphragm to clean out the gunk ?

 

[Luddite Frank]

Some quick smarty-fone photos of the greasy aperture leaves in one of my Miranda 50:f1.9 lenses.

I have two like this... decent glass, but too gunked-up to function.

( Sorry about the glare... I guess I need a polarizing filter for my I-phone... )

 

[OlivierAOP]

I've dismantled a few lenses and generally, once you've removed the front ring it's a matter of removing a few screws to get to the optical group. But to get to the aperture blades you'll have to remove the lens elements. Can't be more specific without the lens in hand.