Fixing Floppy Zoom and Focus Ring : Nikkor 80-200 f4.5

[ic-racer]

I got a beautiful Nikkor 80-200 f4.5. I cleaned the inner elements (those that needed it) based on the detailed desctiption by Richard Haw here.

However, he did not go into how to fix the floppy focus/zoom ring.

I suspect many know the problem; the zoom ring bangs down when the lens is tipped down and slides the other way when the lens is tipped up.

This is how I fixed it.

 

[ic-racer]

Remove the little screw here and unscrew the focus ring. In the Richard Haw web page he didn't remember if it was reverse threaded. Indeed the focus ring is REVERSE THREAD. Twist the focus ring to the minimum focus point and then keep twisting. Mine was not tight at all, but Richard Has indicated his may have had some locking fluid on it (or maybe he turned it too much the wrong way ).

The aperture coupler (bunny ears) needs to be removed for the focus ring to slide off over the lens barrel.

 

[ic-racer]

With the focus ring free, the problem is evident. There has been deterioration of velvet or felt.

I was able to source some sticky-backed felt from McMaster Carr to use as a replacement.

 

[ic-racer]

I used 1/16" thick felt. It was probably a little thicker than the original but I'm very happy with the results. Maybe folks in other countries can source metric material just a tiny bit thinner.

The existing piece was measured and a new piece cut to fit and replaced in the groove (after a thorough cleaning of the groove).

 

[ic-racer]

On my lens, what was just as annoying as the loose zoom was a bad wobble of the focus/zoom ring. I believed some screws were loose, but that was not the case. The friction material inside (at the two yellow arrows) had deteriorated, causing it to wobble. That is how important the friction material is in the construcion and function of this lens. There were no loose screws.

To get to the inside, the helicoid has to be removed. Mark and take out the focus stop (not shown at the front of the lens) and the screw with the green circle. Again, check the Richard Haw pages for better instructions.

Remember to mark where the helicoid comes apart (white dotted line).

My lens had a lot of stray grease. I removed all of it because I did not want any grease on the new felt and did not want grease carried on to the colorful depth of field lines.

 

[ic-racer]

These focus-limit stops need to be removed. Then remove the screw at the green circle. Many screws on my lens were fixed with locking agent; they were very tight, so be careful and use good screwdrivers that fit the screws perfectly.

Even though I have a 'spare' parts 80-200 4.5, it is just slightly different and these screws were different, so I needed to be extra careful.

BTW: I did this disassembly/reassembly on the 'spare parts' lens first, before doing it on the good lens.

 

[ic-racer]

The inner focus/zoom ring is now free. The deteriorated material is evident.

At this point everything was cleaned very well, otherwise after re-assembly, the outside of the lens will be a greasy mess.

 

[ic-racer]

All clean, and now feeding the new felt in to the groove. This ring has two felt strips, one at each end.

 

[ic-racer]

Put it all back together. Don't forget these little screws.

 

[ic-racer]

Look! The zoom ring stays up and won't collapse!

I'm really happy with it. It holds one's zoom position as it is focused and all the wobble is gone from the focus/zoom ring.

 

[mshchem]

Beautiful work!!!
I bought a new Nikon F2S in 1973. I would dream about having this lens. These were fabulously expensive. Seems like as much as the camera. Thanks for sharing this

 

[gorbas]

Well done! Congratulation!

 

[ic-racer]

Not that the lens is fixed, a very important design consideration is evident.

As the focus ring turns, the lens DOES ZOOM. But it is a co-ordinated calculated zoom to keep the image size (angle of view) constant as one is focusing. This eliminates any 'breathing' of the image during focusing.

Without the correct friction, for example holding the focus ring so it won't zoom forward or back, as is the case when it is floppy, the field of view changes with focusing. This makes the lens very difficult to use effectively.

 

[forest bagger]

Look! The zoom ring stays up and won't collapse!

I'm really happy with it. It holds one's zoom position as it is focused and all the wobble is gone from the focus/zoom ring.

Great work!
How many hours did you spend on this?

 

[ic-racer]

Very quick. I already knew how to take it apart, no stuck screws, the felt had adhesive backing, and the helicoid start points are far apart (easy to get the correct one first time).
For the level of disassembly needed, other than the helicoid, there is only a single way to reassemble it.

 

[forest bagger]

Well, thank you for these details. But how many hours were "very quick"?

 

[ic-racer]

Well, thank you for these details. But how many hours were "very quick"?

EXIF data tells me the first image was taken at 10:27AM and the last image taken at 11:38AM. So, just about an hour.

 

[forest bagger]

Thank you, that is about what I assumed.
Again - great work!

 

[Robert Ley]

As I'm just starting to collect the necessary tools and materials for lens and camera repair I haven't come across this felt that you used to repair this lens. Is this a common material (the felt) that you use in your lens repairs?

 

[Alan9940]

As I'm just starting to collect the necessary tools and materials for lens and camera repair I haven't come across this felt that you used to repair this lens. Is this a common material (the felt) that you use in your lens repairs?

I don't want to speak for @ic-racer and I haven't actually worked on my lens, yet, but this is the material I found after a bit of searching:

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com