Loose tab, stuck focus on CV 50 2.5

[froyd]

My CV 50 2.5 has developed some wobble on the focusing tab. Additionally, the focus ring only turns for a small segment of its range. I expect the two issues are related and that a loose screw holding the tab is catching on the focus mechanism and limiting its movement.

I'm wondering if anyone has experienced the problem with this lens or another tabbed optic. How hard is it to correct? Should i leave it to the professionals?

If the repair is as simple as the one Perks performed in this repair thread, I'd be inclined to get myself a lens spanner and have a go at it. The repair in that thread did not involve the tab, and I'm wondering if tightening the tab screws requires more tools than the spanner and small screwdrivers.

Also, any tips on how to go about the operation? Never took a lens apart before. I'd plan to use gloves, a clean working mat, and take a video of the operation so I can reverse the disassembly steps when I need to put the lens back together.

 

[B-9]

Shoot Don at message at DAGCam,

You might be surprised how quickly (and affordable) Don can get you straightened out.

 

[froyd]

I've had both fast and slow turn around from Don, and this is my only 50 so I'd hate to part with it for more than a couple of weeks. I think any local camera repair shop (granted, I'm lucky to have one!) should be able to handle this if it turns out it's more than I dare tackle myself.

 

[Huss]

Where r u located? Walters Camera repair in LA fixed a Nikkor
GN 45 2.8 lens for me in a couple of days. A screw had come loose inside it and prevented it from focussing. $80.

 

[froyd]

Where r u located? Walters Camera repair in LA fixed a Nikkor
GN 45 2.8 lens for me in a couple of days. A screw had come loose inside it and prevented it from focussing. $80.

I'm in PA. There's a repair shop in town that has worked on my Contact before and I trust. They'll probably charge under $100 for the repair. They are an option but I was hoping somebody here would say "Get ye a spanner and have at it, lad. It'd be easy work even for for a monkey"

 

[Phil_F_NM]

Are you close to Philly? I repair lenses and cameras and Mercedes diesels for fun and the meditation of it.
Phil Forrest

 

[Ko.Fe.]

I did Color Skopar 35 2.5 M loose tab, video might helps, but so do the marks.
And threadlock. No idea why it is not applied at first time.
Here is multiple ways these lenses might be tried to be assessed, but only one of them brings lens to its function.

 

[froyd]

Are you close to Philly? I repair lenses and cameras and Mercedes diesels for fun and the meditation of it.
Phil Forrest

Hi Phil, thanks for the offer. I'm a little over an hour away in Lancaster, but my wife is in Philly once a week for work. I'm still tempted to have a crack at it myself unless I hear that it would be a doomed endeavor. Do you think accessing the tab screws is too hard for a noob? I'm relatively mechanically inclined, but lenses are new to me.

 

[froyd]

I did Color Skopar 35 2.5 M loose tab, video might helps, but so do the marks.
And threadlock. No idea why it is not applied at first time.
Here is multiple ways these lenses might be tried to be assessed, but only one of them brings lens to its function.

Noted on the threadlock!

 

[froyd]

Disaster!

Disaster!

Took the rear lens out but that did not do get me any close to the focus screws, so I put everything back together.

Then I took the mount off and revealed 4 black screws, one of which had been mangled by an previous tinkerer who striped the head. I never drilled a screw that small and I'm ready to admit defeat.

To make matter worse the one step I did not photograph was removing the mount from the lens and it seems like there are three possible mounting holes per cardinal direction, as well as 4 ways the mount could be oriented. Any ideas on how to orient things? The mount has a notch that currently I have assembled pointing to the 12 o'clock position, which is what I seem to remember from before taking the mount off. Anyway, tips would be appreciated.

 

[mcfingon]

Presumably only one position will put the lens in the right position when you mount it on the body. Lightly put screws in then mount on body, remove if wrong, moving one notch at a time until you get the original lens orientation to the body.
John Mc

 

[Erik van Straten]

If I remember well the tab is fixed by one or two screws. Just tighten firmly. The lens must be completely dismantled. I remember that the location of the screws is a puzzle.


Erik.

 

[froyd]

So, as mentioned above, I gave up when I saw the stripped screw. Sent to Don and was wowed by the blazing fast turn around.

I sent to Dag on Thursday 8/22. Lens got there by mid-day Saturday 8/24, and on Monday morning 8/26 I already had an email from DAG saying the tab was fixed and the lens cleaned/adjusted as needed. Boom!

 

[Huss]

So, as mentioned above, I gave up when I saw the stripped screw. Sent to Don and was wowed by the blazing fast turn around.

I sent to Dag on Thursday 8/22. Lens got there by mid-day Saturday 8/24, and on Monday morning 8/26 I already had an email from DAG saying the tab was fixed and the lens cleaned/adjusted as needed. Boom!

Excellent! He is my go-to.