Performing Minor Surgery on a Nikkor 24-70mm f/2.8 Zoom Lens
Nikon D4 + Voigtländer 125mm f/2.5 — 1/320 sec, f/2.5, ISO 1800 — map & image data — nearby photos Minor Lens Surgery in ProgressNikkor 24-70mm f/2.8
レンズの手術、始まり点
I've had my Nikkor 24-70mm f/2.8 lens (seen here) for more than eight years. I don't use it all that much anymore because for the last few years I've tended to prefer faster prime lenses, but it's a great lens for many situations.
I'm pretty tough on my gear... I don't baby it, I use it, and this lens is no exception. In particular, after using it all day in heavy snow five years ago (“First Look at Snowy Shirakawago Village”), the zoom became a bit less smooth. It wasn't so bad that it was worth the bother of having it serviced, but it was a slight inconvenience I lived with for years.
Fast forward to a few months ago and it suddenly started getting stuck while zooming... I couldn't zoom out past a certain point. It was hitting a hard stop, as if a bolt had been placed to stop the zoom. The problem came and went... when it came, I found that I could usually unstick things by jiggling the lens, or turning it sideways, or something... I never knew what would get it to work, beyond “futzing with it until it zooms again”, sometimes for several minutes. It was a major inconvenience when I was shooting the big new-year's storm at 3am (“Kyoto At Night During a Heavy Snow”), so I knew I needed to finally get it fixed.
Thinking to bring the lens on my upcoming across-the-country RV trip, I checked Nikon's service website and found that the estimation to fix a troublesome zoom was US$800(!). This is probably for the worst-case scenario... having to replace the guts of the zoom... but mine probably needed only a little TLC. They didn't have a pricepoint listed for “a little TLC”, so I was reticent to send it in.
So, I decided to open it up and fix it myself.
Three resources really helped:
The comment by David Dietrich is painful to read because of his writing style (he comes across like a real jerk), but the information is accurate and invaluable.
In the end, what I did was quite simple...
After using an X-Acto knife to remove a thin glued-on ring that covered the edge around the end of the lens, I was left with the three exposed screws seen in the opening photo.
Removing the three screws (all while leaving the lens covered with a lens-cleaning cloth, as minor insurance) lets the filter-holder pop off, yielding six more screws:
In the shot above, notice that three of the screws are recessed, while the three that are not have some kind of smudge next to them. The smudge is likely Loctite, indicating that those screws should not be removed without a very explicit need. This is where the video made a mistake, which the comment corrected.
With that understanding, I removed the three recessed screws, and the whole front-element unit popped out, leaving the hollow center of the lens open to access:
I applied tiny dabs of silicone grease to the grooves.
結局、美味く修理を出来ました。怖かったけれども。
I would have liked to used lithium grease, but I couldn't find mine, so I went with what I had. I put the six screws and the little cover ring back, and it zoomed just fine. Not “good as new” fine — I have a feeling that lithium grease would have been better — but good enough.
