500mm f/4 issue.

[rosko]

I need some help about about the bayonet ring of my nikkor 500mm f/4 AI-P which has lost a pin contact from black plastic holder. The result is , of course, no more data on picture.
I am not sure I can change it as I cannot see any screw to hold it. It may be glued ?
I am wondering whether I could fill the hole with a tiny piece of copper like a spring to replace the pin ?
Can any one see a solution ?

Thanks,
Francis.

[Birna Rørslett]

This is not uncommon with the 500 AiP, unfortunately.

The pin is spring-loaded by its design on the inside. It can be replaced, but then the entire contact block needs to come off. The block itself lacks the metal backing of the new version which replaced it and opening the block and replacing the pin is tricky. The new model can easily be split thus pin replacement is simplicity itself.

I do have spare pins however not certain I have a free new replacement for your contact block. If you are interested I can have a look after these parts over the weekend. Now I'm off to a trip.

[rosko]

Thanks for your answer, Birna !

Yes I am interested, as I have to put a new pin (with loading spring). No easy to weld it in the bottom of the hole to insure the contact, though ! 

Let me know when you come back, and enjoy your trip !

Cheers, Francis.

[Erik Lund]

No soldering needed.The pin itself is the spring and contact point for the camera as well as contact to the CPU board see this thread for a sample.

You just need a new pin.

https://nikongear.net/revival/index.php?topic=32.0

[MEPER]

A disassembly is needed to insert the new "spring contact"?.....and also how to get a "spring contact"? :-)

I can see now why old lenses can develop bad contacts as there is a contact point between the "flex PCB" and the "spring contact" and form there again to the lens.

[Erik Lund]

You take off the rear light baffle, loosen the CPU contact, remove the F-mount and then contact block comes apart by sliding the two halves apart.
The pins are silver plated for perfect connection.

[rosko]

No soldering needed.The pin itself is the spring and contact point for the camera as well as contact to the CPU board see this thread for a sample.

You just need a new pin.

https://nikongear.net/revival/index.php?topic=32.0

Thanks, Erik, you reassure me !