Re: W-Nikkor 3.5cm F1.8

[nomadia]

Re: W-Nikkor 3.5cm F1.8

Hi all,

I got this lens recently and realized that the focus distance doesn't reach to 3 feet (see photo). Is this normal? I'm not getting any focusing problems on the roll that I ran through it. If defective, is this an easy fix or anyone can point me to a link that has similar problem to mine? Thanks.

 

[Peter Jennings]

It's not right. It should go just a hair past the 3 foot mark. Does the infinity marking line up properly? Does this also happen when not mounted on the body? Get back with answers to these questions and then maybe we can help with a diagnosis.

 

[nomadia]

It's not right. It should go just a hair past the 3 foot mark. Does the infinity marking line up properly? Does this also happen when not mounted on the body? Get back with answers to these questions and then maybe we can help with a diagnosis.

Hi Peter,

The infinity mark lines up and this doesnt happen when not mounted on the camera. I tried this also in another body and same thing happened, it doesnt reach the 3 ft mark.

 

[NIKON KIU]

So, it's fine when you do it without a body?
If that's the case, may be you are not installing it right?
Are you making sure both lens and camera are set at infinity when mounting?

Sometimes the lenses of this vintage gum-up after 50-60 years and they may not go all the way, this should not be any different when on or off the body. I had a 35mm that did this( bind when focusing) but after a few firm turns, it started working all the way.
If you lens turns all the way off the camera, then it sounds like you have a mounting problem.

I think CLA on a lens like this is about $100-$125

Kiu

 

[nomadia]

So, it's fine when you do it without a body?
If that's the case, may be you are not installing it right?
Are you making sure both lens and camera are set at infinity when mounting?

Sometimes the lenses of this vintage gum-up after 50-60 years and they may not go all the way, this should not be any different when on or off the body. I had a 35mm that did this( bind when focusing) but after a few firm turns, it started working all the way.
If you lens turns all the way off the camera, then it sounds like you have a mounting problem.

I think CLA on a lens like this is about $100-$125

Kiu

Thanks Kiu. Yes, I mounted at infinity. This happens only when coupled with the camera.

 

[Peter Jennings]

A well used lens like yours probably has been serviced in the past. My bet is that there was a mistake in the reassembly of the lens. As the helical of the camera extends when focussing at close distances, it could be contacting the inside of the lens mount. Look at the inside of the mount. Do you see any signs of rubbing or paint loss? Regardless, based on the issue you've described, I think the lens needs to be rebuilt.

 

[jonmanjiro]

The infinity mark lines up and this doesnt happen when not mounted on the camera.

My guess is that the spring loaded sleeve around the rear of the lens isn't seating properly in the focus helicoid on the camera. Check for burrs on the corners of that sleeve, particularly on the protrusion with 90 degree corners (not pictured below). Even a small amount will prevent the sleeve from seating properly.

 

[nomadia]

I checked and everything seems to be fine from my non-technical eye. What I noticed though when mounting the lens is it doesnt automatically turn at the first turning of focusing wheel (there's a bit of a lag before it snaps on to infinity). I'm guessing that's where the extra distance is lost.


Sent from my iPhone using Tapatalk

 

[richardHaw]

could it be that the focusing ring has gotten loose? 😱😱😱
they are only held by 3 small set screws 🙄
your lens needs an overhaul

 

[raid]

I would send the lens to a competent lens repair person.

 

[nomadia]

Thank you everyone. I might just as well do that.


Sent from my iPhone using Tapatalk

 

[richardHaw]

i am going to write a teardown one of these days for that lens on my blog 😱😱😱

 

[nomadia]

i am going to write a teardown one of these days for that lens on my blog 😱😱😱

Awesome! Thanks in advance!

 

[Highway 61]

What I noticed though when mounting the lens is it doesnt automatically turn at the first turning of focusing wheel (there's a bit of a lag before it snaps on to infinity). I'm guessing that's where the extra distance is lost.

Like Jon my thought is that the spring loaded sleeve around the rear group of the lens isn't getting seated properly in the focusing helicoid on the camera when you mount the lens with both the lens and the camera focusing helicoids set at infinity. Does the spring loaded sleeve respond snappy to your finger when you push it towards the front of the lens ? Does it show evidence of having got a bump at some point ? The sleeve must be perfectly round and it must not feel sticky around the lens rear group. Also, are the three sleeve tabs - which engage inside the three camera focusing helicoid sectors when you mount the lens - still in good shape with no metal missing ?

When you secure the lens on the camera the lens focusing ring and the camera focusing wheel must be sync'ed immediatly. I'd advise you to give the first amount of focusing motion with the lens focusing ring not the camera focusing wheel.

 

[jonmanjiro]

Like Jon my thought is that the spring loaded sleeve around the rear group of the lens isn't getting seated properly in the focusing helicoid on the camera

Yep, thinking about it a bit more the problem has to be related to this sleeve, especially since the lens focuses through the full range when not mounted on a camera, and there's a moment of hesitation in the focus action when first mounting the lens on a camera.

The sleeve has to sit snugly in the focus helicoid as shown below. If the sleeve is slightly out of round, has any burring, or if the spring isn't strong enough, the sleeve won't seat properly, causing the problem the OP is experiencing.

One option is to remove the sleeve from the lens and fit it in the focus helicoid on its own to see if it fits in smoothy. If the sleeve is the problem (or the spring - I have two spares of those too), you can have one of these spares taken from two reissue W-Nikkor 35/1.8s that were converted to M-mount by Miyazaki-san.

 

[richardHaw]

based on what i know about this lens it is not easy to dislodge the cam/sleeve or put it in the wrong configuration because of the rear elements assembly but it is also possible when the poor screw holding it is worn or damaged 😱😱😱 the spring underneath can be tricky to put back an if this was repaired before then the repairman might've put it back the wrong way.

can you please show us a picture of the rear end of the lens? another thing is the helicoid stop for that lens is delicate. it is just a small screw. 🙄 i doubt that is the cause but that is also one thing that can happen.

 

[jonmanjiro]

The sleeve can be easily damaged by trying to mount the lens on the camera when either the lens or camera (or both) is not set to infinity. Will post a photo of the rear of the lens later!

 

[nomadia]

The sleeve doesn't seem to have any problem. No bumps, it snaps back when pushed to the front of the cell.

 

[nomadia]

Is there a step by step lens disassembly/rebuild resource that I can refer to? Also, I sent my 5cm F1.4 for CLA to Youxin in the past. Will he be a good option for this type of repair?


Sent from my iPhone using Tapatalk

 

[richardHaw]

Is there a step by step lens disassembly/rebuild resource that I can refer to? Also, I sent my 5cm F1.4 for CLA to Youxin in the past. Will he be a good option for this type of repair?


Sent from my iPhone using Tapatalk

i am not sure. i have the notes here and I can write one for you around august if you can wait. 😱😱😱

this lens requires some special tools like a pipe key if you want to overhaul it.
if all you want to do is overhaul the focusing unit, then all you need to do is unscrew the rear elements assembly off but be careful because the optics may fall to the floor 🙄