Removing Nikon RF helical for cleaning?

[SimonPJ]

I have an S2 with a binding helical, which I would like to clean with gasoline, as recommended in several threads that I found searching through the archives.

But I couldn't find details about how to remove the helical. It looks as if the front plate needs to come off first.

Can any body provide instructions for how to do this, or point to a source online? How easy a job is it? Does it involve dis-assembly and re-assembly of any complex mechanisms underneath the front plate? I'm pretty cautious when it comes to this kind of thing!

Thanks,

Simon.

[Brian Sweeney]

I have done this.

After removing the front bezel, three screws will be revealed that hold down the helical. The very small washer-like shims are also held in place by these screws, under the mount. Do not lose them, and they are usually "sticky" from dirt/oil.

Let the helical air out for 24hours after cleaning.

One "Quickie" that you could try is "flood cleaning" the helical with Ronsonol. I remove the lens and set the camera to "T" to open the shutter. Squirt ronsonol into the back of the helical, work the mechanism, swab it with lens cleaning paper on a q-tip. Should go from dirty black/grey to fairly clear.

[SimonPJ]

Thanks Brian. That's helps!

[Mike Kovacs]

Really Brian, only three screws holding the mount?

4 on the prewar Contax
5 on the postwar Contax

Most of us don't hang a 180 Olympia with a reflex housing off our cameras, but I wonder how strong the Nikon mount is?

[Brian Sweeney]

Four screws. This is why I take pictures.

[Mike Kovacs]

Ha ha - I may be curious but not curious enough to disassemble a E+ to mint -, perfectly working Nikon S :)

[Brian Sweeney]

The Nikon S has way more screws holding the Helical in. I have not had to remove one, but have Tomosey's reapair manual on it. They seem to have followed: if a little bit is good, a lot is better. The shims are not under the screws that hold the helical in place. They are at the film gate. That is the reason for the extra piece on the film back, and the reason why the camera and back require matching serial numbers.