Focusing ring failure Hexanon 50mm 1.7 - Help & Advice please!

Discussion in 'Adapted Lenses' started by pdh, Sep 30, 2010.

  1. pdh

    pdh Mu-43 Top Veteran

    598
    May 6, 2010
    My lovely "new" Hexanon has completely failed tonight.
    The focusing ring is just spinning endstop-to-endstop without actuating the mechanism.

    Obviously I'm getting back to the eBayer that I bought it off, but it wasn't a huge amount of money and frankly it's likely to be more trouble than it's worth returning for a refund, assuming he'll do that.

    I'm guessing that under the rubber grip there'll be two or three grubscrews that are either loose or missing, so I'll have a look if I keep it, but my guess may be wrong.

    Any suggestions otherwise?

    thanks
     
  2. snkenai

    snkenai Mu-43 Top Veteran

    523
    Sep 5, 2010
    More likely the "tang" inside that holds alignment, has probably come loose. It is held in place by 2 tiny screws. It is easy to check. Remove the 4 screws that hold the base in place. CAREFULLY lift off while holding lens base up. The tang is brass colored. there are two brass colored pieces. The bigger and closser to the open end is NOT the one. It is the smaller one 180 degrees and deeper. If screws are missing, they will be loose in this space and may be hiding stuck in some greese.

    I have disassembled and cleaned mine. But at that level you have to take the helical apart, and it is very difficult getting it in the right thread when reassembling. I don't want to do it again. But for checking your problem, you only have to pull the base plate and look. Easy.

    If that is your problem you will have to realign the tang with a wide grove in the outer barrell.

    Hope this helps.
     
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  3. Ulfric M Douglas

    Ulfric M Douglas Mu-43 Hall of Famer

    Mar 6, 2010
    Northumberland
    Great lens and quite easy to disassemble but be careful and notice everything about the alignment of the plates as you take it apart... do it in a tray too.
     
  4. pdh

    pdh Mu-43 Top Veteran

    598
    May 6, 2010
    OK thanks.

    I've carefully removed the back plate but can't see anything obviously missing or loose, plus I also found this old thread elsewhere
    The Classic Camera Repair Forum: Konica 50mm 1.7
    Disassembled, my lens looks exactly like the pic by "Reborn7" there.

    I can see two brass pieces, as you describe snkenai but can't see how they relate to the focussing ring -- looks like one makes a cam/ratchet to lock the aperture ring to the "AE" setting.

    I've also slipped off the rubber grip and found three holes but no screws.

    I'm wondering if the engraved ring retaining the objective may have to come off.
     
  5. snkenai

    snkenai Mu-43 Top Veteran

    523
    Sep 5, 2010
    I have two of the 50mm 1.7 hexanon ar lenses. the one I'm looking at does not have screws or holes under the focusing ring rubber grip. Are there more than one version of these lenses? But if you have holes without screws it might be time to contact seller, OR use the lense for further education. I sometimes do that.
    I'm sorry not to be more help. But it sounds as though you are better equiped with instructions for maintaince, than I am.
     
  6. pdh

    pdh Mu-43 Top Veteran

    598
    May 6, 2010
    I appreciate your help anyway Steve ... yep there was more than one version of most the Hexanons -- or so I learn from www.buhla.de - Konica start page
    Oh well, I'm waiting for an answer from the seller, but as I say it was cheap so perhaps not worth the effort ... I'm sure he has sold it in good faith though, I think I've just been unlucky ... it is a real shame though, as the optics are absolutely perfect on this example and it's sharp as you like stopped down a bit ... how annoying!
     
  7. Vulcanrider

    Vulcanrider Mu-43 Rookie

    12
    Feb 19, 2010
    I have two Hexanon's for my GH1. I'm keeping this page and the link (from pdh) just in case.

    Good luck with your repair effort.

    Alan
     
  8. Ulfric M Douglas

    Ulfric M Douglas Mu-43 Hall of Famer

    Mar 6, 2010
    Northumberland
    Try screwing a tiny spare screw into one of those empty holes and see if the internals move when you turn it. Have a few goes : nothing will harm and it might solve your problem.
    Those grub screws are very very easy to lose : they look like bits of dirt when they fall on the floor.
     
  9. pdh

    pdh Mu-43 Top Veteran

    598
    May 6, 2010
    unfortunately they are just unthreaded holes, and looking carefully through them to the barrel beneath while turning the ring shows no matching holes either, nor any marks where a retaining screw might have operated.

    For a laugh I've asked a few repairs shops to quote ... one was "from £55 plus carriage plus VAT" (always annoying to be quoted ex-VAT but that's probably because they do lots of work for pros who are VAT registered).

    Think I better just haunt eBay some more and buy another ...
     
  10. Ulfric M Douglas

    Ulfric M Douglas Mu-43 Hall of Famer

    Mar 6, 2010
    Northumberland
    I took a photo when I was making a new part for my Hexanon.
    your slider for the focus thingy is here ;
    [​IMG]
    It holds everything in line while the helix moves the lens body in and out.
    The big silver back and little black back plates are off...

    ( On my lens someone had fudged up the aperture lever connections : I ripped them out and made my own. The debris from various meddlings is visible on the picture.)
     
  11. pdh

    pdh Mu-43 Top Veteran

    598
    May 6, 2010
    ok thank you UMD... I have whipped the back plate off to reveal the innards thereunder ... now, I think in order to get to the part you are referring to, something else has to come out, but I can't see what or indeed how ... I have removed two tiny brass grub screws (at approx 5 and 10 o'clock in my pic) to no avail ... there are hairsprings in both the brass assemblies in the edge recesses, which I am loth to touch, because I know from experience that without specialist skills I am unlikely to ever get them back in ...
     

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  12. Ulfric M Douglas

    Ulfric M Douglas Mu-43 Hall of Famer

    Mar 6, 2010
    Northumberland
    It looks to me that you do have the brass slidey thingy : just above centre on the right of your picture : about three growth-rings out from the glass. :)
    So your focus problem seems not to be a missing/loose brass slidey thingy.

    But your lens looks unlike my lens ... so showing bits of mine probably can't help you further.
    To help identify your lens please write the words on the front (or post another nice piccy). Some expert might see it and say "Ah yes, the second-half of 1971 lenses made in Yokohama Koki 13 have a bio-degradeable plug widget" or some such.

    Mine says "KONICA HEXANON AR 50mm F1.7 LENS MADE IN JAPAN 55@"
    (It's not an @ its a crossed zero ...)
     
  13. pdh

    pdh Mu-43 Top Veteran

    598
    May 6, 2010
    yeah mine says that too.
    the brass slidey thingy on the right on mine is a springcamratchet arrangement for locking and releasing the aperture ring in and from the "AE" position.
    I want give in, but I hate waste. And it takes lovely sharp photographs.

    I bet I end up paying twice what the lens is worth to get it fixed.
     
  14. Ulfric M Douglas

    Ulfric M Douglas Mu-43 Hall of Famer

    Mar 6, 2010
    Northumberland
    Never mind the ratchet.
    you see the little brass thing just higher than centre, 3 'rings' out from the lens.
    That is probably (more pics) the locator brass thingy that slides in and out keeping everything from rotating as the focus is turned...
    If that isn't fixed with two screws on its bast then that'd be the problem. Focus the front away from the back and have another look.
    Also, try screwing three tiny screws into the focus ring empty holes so they grip the interior : never mind lack of evidence therin. It might just work.

    Mine cost me £8.27 with Autoreflex body and a nice brochure. Result!