Nikon FM rebuilding

[MFstooges]

I am rebuilding a broken Nikon FM and upon opening the top cover I found decaying foam material on both sides of viewfinder. I am planning to cut new material but there are two small lens on left and right side of VF and I'm concern if I will block them from light path. Anybody can describe or post picture how the original foam looks?

Here's the picture of the FM viewfinder area, you can see the decaying foam on left and right of VF just under the small lenses (they're almost disappear).

PS. Oh and I hope anyone interested or having info in rebuilding Nikon FM can post on this thread for future reference. I hope you don't mind.

 

[dehk]

Those 2 small lens you are talking about are light sensors for the meter. as long as you don't block the front (towards the prism) of it. Foam are probably blocking stray light from going to the sensors.

 

[MFstooges]

Those 2 small lens you are talking about are light sensors for the meter. as long as you don't block the front (towards the prism) of it. Foam are probably blocking stray light from going to the sensors.

Thanks. Do you think it's better to tape the backside of that lens than installing foam?

 

[John Koehrer]

The foam goes under the eyepiece and works as a light shield.

 

[wblynch]

Try felt or fabric as a replacement. New foam will only rot again.

 

[dehk]

I second what wblynch said.

 

[MFstooges]

I happen to have piece of foam so decided to use that. I know it will rot again but probably will outlast myself Not as nice as expected but OK I guess.