Nikon F4 rewind knob disassembly

[hartacus]

Hi all,

I'm still trying to diagnose my Nikon F4's shutter issues, and in doing so I'm trying to take off the left top cover (to check rewind functions, make sure nothing's jammed that would cause a sequence error, etc., c.f. http://photographic.co.nz/cameraworks/cameras/nikon_f4_rewind/). But the screw in the centre of the rewind knob won't budge. I've put rewind switch R2 down as advised in the repair manual, and am applying torque to the film end of the rewind axle to prevent movement, but it will not move. Despite my best cares the screw head is starting to get stripped.

I've not found any online sources that give a detailed and/or videographic run-down of removing the rewind knob or the left top cover (or they seem to gloss over it, like the above site: "The plastic top-left body cover comes off easily"). So for the sake of my sanity could someone please confirm... that's not a reverse-threaded screw, is it?

 

[shutterfinger]

Two possibilities come to mind:
1. its a left hand thread, turn right (clockwise) to loosen; left (counterclockwise) to tighten.
2. thread locker was used on the threads to prevent it from coming loose. apply acetone to the screw head and allow it to penetrate the threads. this may take several applications and 30 minutes to an hour to dissolve the threadlocker.

 

[hartacus]

Two possibilities come to mind:
1. its a left hand thread, turn right (clockwise) to loosen; left (counterclockwise) to tighten.
2. thread locker was used on the threads to prevent it from coming loose. apply acetone to the screw head and allow it to penetrate the threads. this may take several applications and 30 minutes to an hour to dissolve the threadlocker.

Thanks for your reply. I've applied some acetone a couple of times and will try it again tonight.
I'm not sure if it's left hand thread - that would mean that rewinding film would apply torque to the screw in the direction of undoing it, right? But I'm hoping someone who's taken apart an F4 before could confirm.

 

[John Koehrer]

Ummm, set screw in the RW knob? If there is it would likely be in the recess that the lever folds into. If the acetone fails you can
also try heating the screw with a soldering iron.

 

[hartacus]

Got it! Acetone freed up what appears to be threadlocker (black stuff), and I used a Moody Screw Extractor to get purchase on the screw head. Thanks for your help all

EDIT: for future reference it is a normal threaded screw, undo it counterclockwise