[toukan]

So I was out shooting recently, testing out a recent purchase (SMC 35mm 3.5) and being in a hurry, i placed my M42-K mount adapter on the lens backwards, and now i cant get it off. So now the front face of the adapter is facing the what would be the camera body. I have tried turning it, but it only goes as far as the spring, but no further. I am hesitant to really crank on it because i dont want to damage anything, and they are not only seemingly getting harder to find, but more expensive. Any help would be appreciated. Thanks.

[cyberjunkie]

It has to come off.
Try unscrewing the little screw, at least partially.
Even mounted properly, sometimes I had to use a cap opener to unscrew the adapter, if I used too much force fitting it.
Sometimes I do it on purpose, leaving the ring attached to the lens with no spring/screw.
Recently I'm using cheap chinese knock-off's with the spring removed for permanent or semi-permanent adaptations.

Cheers

Paolo

[stevebrot]

So now the front face of the adapter is facing the what would be the camera body. I have tried turning it, but it only goes as far as the spring, but no further.

Is the adapter stuck on the lens or is it engaged with the body? I fear you are describing the latter, but since the lens is SMC it is possible that it is hung up on the small interlock pin on the lens mount face. Look carefully at the edges of the mount tangs for this small pin. When you find it, press it down and slide the A/M switch to the A (Auto) position. That should retract the pin almost completely to allow the adapter to rotate off. If the retraction is not enough, press the pin fully down and carefully rotate the adapter counter-clockwise with the pin sliding underneath. The rotation should lift the adapter clear of the pin.

P.S. I did a dry run of this solution on my S-M-C 28/3.5 just before posting. Be very careful and FORCE NOTHING. You don't want to damage the interlock mechanism on the lens.


Steve

[Not a Number]

If it is one of the Takumars with the clutch pin for the A/M switch the adapter is probably catching on the pin. You need to work a thin piece of metal in there to keep the pin from catching. A feeler gauge should work or the metal shutter off an old floppy disk would do. You should be able to see the pin. You might be able to just push the pin down with a small screwdriver as it should be visible in the cutout on the adapter.

The pin can be seen on the left on the lens base.

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Last edited by Not a Number; 01-02-2018 at 01:47 AM.

[stevebrot]

The pin can be seen on the left on the lens base.

Thanks for providing the photo. I was too lazy


Steve

[toukan]

Thank you for that! I was finally able to go and work on it. It was indeed the clutch pin on the face of the lens mount. The adapter ring would slide all the way around until the cutout for the lock mechanism on the adapter was in front of the pin, and that's where it was hanging up. An exacto knife was slim enough to fit in, and then it slid off easily. Thank you again!