| View previous topic :: View next topic |
| Author |
Message |
fermy
Joined: 17 Feb 2012
Posts: 2877
|
 Posted: Fri Sep 21, 2012 8:38 pm Post subject: Zebra Zeiss Jena Sonnar 3.5/135mm aperture repair |
 |
|
fermy wrote:
I've obtained a Sonnar with stuck aperture blades (enormous amount of gunk). Can anyone point me to a good guide for this lens. I can probably easily get the optical block out. However, I have two questions.
1. Does one unscrew the optical block from the front (like with Flektogon) or from the back? If from the front, then the front part of the focus ring (with zebra stripes) unscrews, right?
2. Once the optical block is out, what's the most efficient way to get to the blades?
_________________
Many lenses and some film bodies for sale here: http://forum.mflenses.com/canon-fd-minolta-md-c-mounts-m42-pentax-and-more-t50465.html
Flickr http://www.flickr.com/photos/96060788@N06/ |
|
| Back to top |
|
 |
fermy
Joined: 17 Feb 2012
Posts: 2877
|
| Posted: Sun Sep 23, 2012 1:31 am Post subject: |
|
|
fermy wrote:
Folks, please don't be shy. I am sure many around here tended to an ailing Zebra Sonnar at some point...
_________________
Many lenses and some film bodies for sale here: http://forum.mflenses.com/canon-fd-minolta-md-c-mounts-m42-pentax-and-more-t50465.html
Flickr http://www.flickr.com/photos/96060788@N06/ |
|
| Back to top |
|
|
Excalibur
Joined: 19 Jul 2009
Posts: 5017
Location: UK
Expire: 2014-04-21
|
| Posted: Sun Sep 23, 2012 8:17 am Post subject: |
|
|
Excalibur wrote:
| fermy wrote: |
| Folks, please don't be shy. I am sure many around here tended to an ailing Zebra Sonnar at some point... |
Might be of some help:-
I had stuck blades on CZJ 35mm flek and 135mm Sonnar (both non Zebra) and from the back just unscrew the larger screws of the M42 mount and take this off and you can add the lighter fuel in places while you can operate a small lever to open and close the blades...sooo easy to do as when the blades stuck on holiday I took the flek apart to get the blades working (as if stored wide open they stick)....but my problem is not gunk on the blades but because of not being used for many years (if at all).
_________________
Canon A1, AV1, T70 & T90, EOS 300 and EOS300v, Chinon CE and CP-7M. Contax 139, Fuji STX-2, Konica Autoreflex TC, FS-1, FT-1, Minolta X-700, X-300, XD-11, SRT101b, Nikon EM, FM, F4, F90X, Olympus OM2, Pentax S3, Spotmatic, Pentax ME super, Praktica TL 5B, & BC1, , Ricoh KR10super, Yashica T5D, Bronica Etrs, Mamiya RB67 pro AND drum roll:- a Sony Nex 3
.........past gear Tele Rolleiflex and Rollei SL66.
Many lenses from good to excellent. |
|
| Back to top |
|
|
fermy
Joined: 17 Feb 2012
Posts: 2877
|
| Posted: Sun Sep 23, 2012 1:07 pm Post subject: |
|
|
fermy wrote:
Yeah, I already did open the back part and found that there is a hearty layer of gunk on the blades. It looks as if someone spread the lubricant over the blades to make them operate smoother 
Without operating the lever with considerable force the blades wouldn't move at all. I don't think I can fix that by working the lighter fluid in.
_________________
Many lenses and some film bodies for sale here: http://forum.mflenses.com/canon-fd-minolta-md-c-mounts-m42-pentax-and-more-t50465.html
Flickr http://www.flickr.com/photos/96060788@N06/ |
|
| Back to top |
|
|
Excalibur
Joined: 19 Jul 2009
Posts: 5017
Location: UK
Expire: 2014-04-21
|
| Posted: Sun Sep 23, 2012 7:22 pm Post subject: |
|
|
Excalibur wrote:
I have seen (pictures) how to dismantle the blades somewhere of a similar model but can't find the link, but you could start here:-
http://www.kyphoto.com/classics/forum/messages/2/19687.html
"Thanks for the response. I did manage to find a service manual for CZJ lenses on Rick Oleson's site and it includes a great mechanical cross section of the model I have. You are right, the rear element just unscrews inside its tube once you get the rear internal lens hood off. With the rear element out I was able to use cotton buds to swab clean the aperture and it now seems to work fine. This was a very simple job to do with no real tricky disassembly or reassembly."
_________________
Canon A1, AV1, T70 & T90, EOS 300 and EOS300v, Chinon CE and CP-7M. Contax 139, Fuji STX-2, Konica Autoreflex TC, FS-1, FT-1, Minolta X-700, X-300, XD-11, SRT101b, Nikon EM, FM, F4, F90X, Olympus OM2, Pentax S3, Spotmatic, Pentax ME super, Praktica TL 5B, & BC1, , Ricoh KR10super, Yashica T5D, Bronica Etrs, Mamiya RB67 pro AND drum roll:- a Sony Nex 3
.........past gear Tele Rolleiflex and Rollei SL66.
Many lenses from good to excellent. |
|
| Back to top |
|
|
fermy
Joined: 17 Feb 2012
Posts: 2877
|
| Posted: Mon Sep 24, 2012 1:05 am Post subject: |
|
|
fermy wrote:
Thanks! I did have the hood off, but couldn't unscrew the rear element. But now that I reread this sentence, I've realized that I've been an idiot. I tried to twist the whole back of the optical block off, while the rear element is screwed into it. Bingo! Will try that tomorrow.
_________________
Many lenses and some film bodies for sale here: http://forum.mflenses.com/canon-fd-minolta-md-c-mounts-m42-pentax-and-more-t50465.html
Flickr http://www.flickr.com/photos/96060788@N06/ |
|
| Back to top |
|
|
fermy
Joined: 17 Feb 2012
Posts: 2877
|
| Posted: Tue Sep 25, 2012 12:02 am Post subject: |
|
|
fermy wrote:
Success!
My first instinct was right, apparently I just were too gentle. Opened from the rear, unscrewed the rear hood, then unscrewed the rear lens group that was covered by the hood. Couldn't take the aperture out for flood cleaning, but cleaning the backside with alcohol fuel unclogged the mechanism. There are still traces of gunk on the blades, but the aperture is very snappy, like a new one.
_________________
Many lenses and some film bodies for sale here: http://forum.mflenses.com/canon-fd-minolta-md-c-mounts-m42-pentax-and-more-t50465.html
Flickr http://www.flickr.com/photos/96060788@N06/ |
|
| Back to top |
|
|
pooschey
Joined: 03 Jun 2010
Posts: 21
|
| Posted: Tue Sep 25, 2012 2:23 am Post subject: |
|
|
pooschey wrote:
| fermy wrote: |
Success!
My first instinct was right, apparently I just were too gentle. Opened from the rear, unscrewed the rear hood, then unscrewed the rear lens group that was covered by the hood. Couldn't take the aperture out for flood cleaning, but cleaning the backside with alcohol fuel unclogged the mechanism. There are still traces of gunk on the blades, but the aperture is very snappy, like a new one. |
So you can access the blades without touching the infinity focus setting screw? I had been hesitant to follo the instructions in the link for a long time, as I'm not exactl keen on messing up infinity focus, even though my lens is affected by sticky aperture blades now and then, when I forget to reset it to minimum aperture after use.
I'll give this a shot following your approach. |
|
| Back to top |
|
|
fermy
Joined: 17 Feb 2012
Posts: 2877
|
| Posted: Tue Sep 25, 2012 12:09 pm Post subject: |
|
|
fermy wrote:
Yes. You can do so without touching anything of essence. I was taking off the stop down levers to get easier access to the rear element, but it turned out unnecessary.
_________________
Many lenses and some film bodies for sale here: http://forum.mflenses.com/canon-fd-minolta-md-c-mounts-m42-pentax-and-more-t50465.html
Flickr http://www.flickr.com/photos/96060788@N06/ |
|
| Back to top |
|
|
pooschey
Joined: 03 Jun 2010
Posts: 21
|
| Posted: Tue Sep 25, 2012 3:09 pm Post subject: |
|
|
pooschey wrote:
| fermy wrote: |
| Yes. You can do so without touching anything of essence. I was taking off the stop down levers to get easier access to the rear element, but it turned out unnecessary. |
OK, thanks. I'll give it a try then. |
|
| Back to top |
|
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
Search
Memberlist
Register
Profile
Log in to check your private messages
Log in
