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Jack Abbott
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, December 21, 2005 - 09:24 am: | 
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Hi
I would appreciate some pointers to help me separate the front and rear lens portions of my FL 35mm 2.5 lens as the diaphragm has all but seized-up. I removed the front lens asm and the breech locking ring and aperture lever asm from the rear. The front and rear lens asm's can now be wound out from the focussing ring but will not separate to give access to the diaphragm. Is there a hidden screw or catch that I am missing? Any help would be welcome. The camera is an old pellix that I would love to bring back to life. Thanks in advance.
Jack |
rick
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, December 21, 2005 - 10:49 pm: |
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i've never disassembled the FL 35/2.5.... i do have sketches and notes from the FL 50/1.2. i don't know if the construction is similar enough for them to help, but you're welcome to them.
in that lens, it seems a bit more complicated than some other lenses: first you remove the BL mount, then unscrew a retaining ring at the rear to pull the entire lens cell out of the focusing mount. then you remove the aperture ring from the lens, and unscrew the front ID ring and the front lens cell to get to the diaphragm. once you reach it, the entire diaphragm comes out in a neat subassembly, not a handful of loose blades like in other lenses......
 = |
Glenn Middleton
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, December 22, 2005 - 08:32 am: |
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From a late friend's repair records, it would appear that Rick is correct in his thoughts on the similarities between the FL series. However there are only details for the 50/1.2, on the 35/2.5 he just stated 'assembly screws out'.
Sorry that I cannot really give any more information, than Rick has already written. |
Jack Abbott
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, December 22, 2005 - 11:25 am: |
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Rick and Glenn,
Thankyou for your help. Rick's descriptions have given me a clue. There is indeed a retaining ring (about 1" diameter) around the rear lens group that seems to hold the lens to the brass focussing plate. I will make a tool to fit the notches and attempt to remove it but to hold such an assembly together it must be tight.
Rick. Can you remember if it is a right hand thread?
Regards, Jack |
Perter Wallage
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, December 22, 2005 - 12:30 pm: |
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Hi Jack,
I took a 50mm FL lens apart some time ago to clean the helicoid and the diaphragm but looking at my notes I didn't take the diaphragm assembly out. After I took out the front lens group I took off the breechlock etc and then took the helcoid apart to clean it (left hand thread) because it was stiff. The rear lens group unscrewed (right hand thread) but the slots for the spanner were very small and I had to make up tool to fit them. This gave me access to both sides of the diaphragm which I cleaned the by flood-washing with Ronsonol (naptha) and kept working the leaves till it was dry and clean. I didn't make any sketches, and my notes are rather brief. I can't now remember what holds the helicoid from unscrewing, but though it would be more awkward I seem to remember that it would be possible to unscrew the rear lens group without taking the helicoid apart.
Peter |
Jack Abbott
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, December 22, 2005 - 07:16 pm: |
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I am overwhelmed by the response to my problem. Thanks to you I now have the diaphragm in my sticky hands, all six pieces, and what a beautiful piece of engineering they are.
Peter. Your memory is excellent and the crude tool I made removed the locking ring around the rear lens asm and separated the diaphragm asm from the rest. It was then just a matter of removing locking screws, brass shim circlips (for want of a better word) and distance pieces. Restoration can now begin and I thank you all again for your help.
Jack |
Rock
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, January 01, 2006 - 07:20 pm: |
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Jack and all-
A little web-surfing has brought me to this page only a few days after your latest post. I would love to get hold of your notes. I have a case full of great old Canon FL lenses which have sticky diaphragms. I'm currently working on an 85/1.8 and next up is my 35/2.5 (same as yours, Jack). But I have to solve the 85 first.
I've been working off of Rick's notes for the 50/1.2 (Thank you, Rick). Rear dissasembly is similar to Rick's notes. The front is different however. Rank amateur that I am, forgive me in advance for dopey questions. I cannot see a way to remove the front lens elements. There's simply the filter threads, then a black ring with all the white engraved lettering and then the (beautiful) glass of the front of the lens. There are no slots or pin-holes in the black ring to put a spanner as I see on the 35mm lens.
Any clues as to my next move?
Thanks,
Rock |
Henry
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, January 02, 2006 - 09:37 am: |
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Friction...the nameplate ring "probably" unscrews, most do. Find a suitably sized rubber something...something like furniture leg pad, sink stopper, be creative. They are rarely tight. I have even swiped my wife's dishwashing gloves and unscrewed them with my thumbs. The trick is NOT to rub or turn against the front glass.
I have ran across a couple that were horribly over tightened (or threads were messed up) and drilled a couple spanner holes. WARNING...only do this as a last resort. And never drill as deep as you think you can!
Henry |
