Does Nikon FM not have a film advance lock???

<p>OK i have tried out two Nikon FM's the last week or two and have noticed something funny with both of them, It seems like after i advance the film I am able to advance the film again without ever releasing the shutter. After the initial advance if i try to advance it again it doesnt seem to take too much to do so, i mean it is not as easy as the initial but its not that hard either. I have olympus OM's and they seem to lock completely until the shutter is released. Is this a feature or something of the Nikon FM's? I had a Nikon FM2n in the past and it didnt seem to do it either.</p>

<p>Thanks</p>

<p>Both of them were defective and needed repair. The wind mechanism in the base plate (for all of the FM/FE series) has a "notched cam" (directly above the motordrive coupling) and a lever with a "hook" on the end. At the end of the first film advance, the hook on the lever engages the notch in the cam, and the film advance is locked until the shutter is released.</p>

<p>It is sometimes a simple repair, as the hooked lever can be bent just enough (if someone forced the advance) so that it doesn't quite lock into the cam notch. If that's the case, removing and straightening the hooked lever will make things right. When I have come across this in the past, I was able to feel the lever hook slip off of the cam as the second advance was made.</p>

<p>But if the cameras have seen heavy use, and the cam or lever is worn, then parts would likely need to be replaced.</p>

<p>The photo below shows the mechanism described above before film advance. As the film is advanced, the cam rotates clockwise to engage the hooked lever. From an FE2, but the FM should be very similar.</p>

<p>Thanks, for the quick reply and glad to know it is not normal</p>

<p>i dont see the image though</p>

<p>For some reason or another my other posts did not upload. I'll try again.</p>

<p>Before advance (film wind lever free to rotate):</p><div></div>

<p>... and after advance (film wind lever locked):</p><div></div>

<p>... and I should have really labeled the "A" lever as "double <strong>wind</strong> prevention", as a double wind results in a blank exposure, not a double exposure. But these are from about a year ago, and I'm too lazy to fix 'em. ;-)</p>

<p>The multiple exposure mechanism (shutter charges, but film does not wind) is another unrelated part.</p>

<p>it seems like when i advance it the hook on the end of a is not perhaps pressed against b enough to where a bit of strength will knock it loose allowing me to adance again so would that mean that A may need to be modified? Like if i press a against the cam just barely it seems to lock it.</p>

<blockquote>

<p><em>... "A" may need to be modified?</em></p>

</blockquote>

<p>The hook on the end of "A" should be a perfect 90 degree right angle. If it is bent even a little so that the hook is the least bit "open", then it will slip off of the charge lever notch.</p>

<p>I have access to a small fly-tying vise, so I was able to straighten the bent lever on the camera above in my tying vise. "A" is fairly easy to remove ... just take a pair of tweezers to slip the spring off the end, remove the single screw, lift the lever off of the post, straighten it, then replace in reverse.</p>