Well, full reassembly is not really required. You have to start with
basically correct mechanical positions. When you screw the helicoid in
and almost all the way down (infinity) the 2 slots in that tube have to
line up with the 2 sets of screw holes which hold the keys in. One
thing that makes this all more difficult is if the focus ring had been
taken off, in which case you lose the original infinity setting. If you
screw the helicoid down, focus ring is at infinity, and the key slots
line up, then you put the keys in. Then you can fine tune infinity by
adjusting the position of the focus ring.
If the helicoid is not screwed down far enough before the keys go in,
and lens is set up that way, the first time you focus out for close
focus, helicoid will probably become disengaged again.
___________________________________
John Hermanson
Camtech Photo Services, Inc.
21 South Lane, Huntington NY 11743
631-424-2121 | Olympus OM Service since 1977
http://www.zuiko.com | omtech1 AT verizon.net
Johann Thorsson wrote:
> Thank you for the advice, I will keep trying. The annoying thing is that
> you have to put the whole lens together before you know if you succeded or
> not.
>
> J
>
> ----- Original Message -----
> From: "John Hermanson" <omtech1@xxxxxxxxxxx>
> To: <olympus@xxxxxxxxxx>
> Sent: Thursday, July 06, 2006 06:43
> Subject: [OM] Re: Fixing non-focusing lenses
>
>
>
>>Sounds like the focus helicoid was unscrewed. The thread has multiple
>>starting points, so if the correct one is not used, it will not focus
>>properly and diaphragm levers will be in the wrong place. If you have
>>another 1.4 to compare it to, remove the rear mount to see where the
>>inner barrel should be when focused to infinity. Remove the keys from
>>the defective lens (2 metal "fingers" that extend into the lens, held
>>into lens by 2 screws each), screw the front barrel out until the
>>threads disengage (you can mark the point of disengagement with a pencil
>>on the edge of the filter ring, lined up with where infinity mark on
>>focus ring is. Hopefully focus ring has not been taken off. I do not
>>know to what point this lens has been dis-assembled).
>>
>>Keep turning slightly until next set of threads click in place, screw
>>into lens most of the way and see if slots in tube line up with where
>>the keys go. Eventually, you'll try all the starting points, one of
>>which is correct.
>>
>>___________________________________
>>John Hermanson
>>Camtech Photo Services, Inc.
>>21 South Lane, Huntington NY 11743
>>631-424-2121 | Olympus OM Service since 1977
>>http://www.zuiko.com | omtech1 AT verizon.net
>>
>>
>>Johann Thorsson wrote:
>>
>>>Many years ago I was given a 50mm f/1.4 lens. The focusing barrell had
>>>somehow unscrewed and fallen out of, and the owner decided it wasn't
>>>worth
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