Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,967   Posts: 1,558,451   Online: 980
      
Page 1 of 3 123 LastLast
Results 1 to 10 of 27
  1. #1
    Sanjay Sen's Avatar
    Join Date
    Mar 2005
    Location
    New York, NY
    Shooter
    Multi Format
    Posts
    1,251
    Images
    4

    Jammed (process) lens - need your help

    Hi,

    This relates to a JML Optical 305 f:9 process lens (in barrel): I was trying to separate the front and rear elements/sections of this lens, and managed to get it jammed. It is now unscrewed half-way, and I cannot get it to unscrew completely, nor can I get it back where it was to begin with. What should I do to fix this? (I don't really need to take the sections apart.) Is there a gel, or something else, that I can use to loosen the jam?

    I was using my bare hands, and then gloves, but it's jammed too tightly for me to unjam.

    Also, I am guessing that the extra spacing that now exists between the front and rear elements/sections will be a problem, correct?

    Thanks for your help!


    Best wishes,
    Sanjay

  2. #2

    Join Date
    Jan 2005
    Location
    Live Free or Die
    Shooter
    Multi Format
    Posts
    4,468
    Images
    90
    You might try PM'ing Jim Galli. Worst case, he can apparently sell you a replacement.
    Is there a set screw in the barrel acting as a stop?

  3. #3

    Join Date
    Mar 2005
    Shooter
    Multi Format
    Posts
    3,462
    Sanjay, as is, it is useless. Jim Galli is selling one right now on the LF forum, he's asking $85. Balance that against the likely cost of having, e.g., SKGrimes fix yours and don't forget to include the cost of postage both ways.

  4. #4
    Sanjay Sen's Avatar
    Join Date
    Mar 2005
    Location
    New York, NY
    Shooter
    Multi Format
    Posts
    1,251
    Images
    4
    Quote Originally Posted by bdial View Post
    Is there a set screw in the barrel acting as a stop?
    I don't think so - I cannot even screw it back like it was.

    Quote Originally Posted by Dan Fromm View Post
    Sanjay, as is, it is useless. Jim Galli is selling one right now on the LF forum, he's asking $85. Balance that against the likely cost of having, e.g., SKGrimes fix yours and don't forget to include the cost of postage both ways.
    Oh, no! I wasn't planning on sending this to SKG. I was looking for a DIY solution, if there exists one.


    Thanks to both of you for replying.


    Best,
    Sanjay

  5. #5
    JBrunner's Avatar
    Join Date
    Dec 2005
    Shooter
    35mm
    Posts
    6,781
    Last resort- put it in the freezer- get it pretty cold - not freezing- dip one end into warm water- immediately try to separate.

  6. #6
    Sanjay Sen's Avatar
    Join Date
    Mar 2005
    Location
    New York, NY
    Shooter
    Multi Format
    Posts
    1,251
    Images
    4
    Quote Originally Posted by JBrunner View Post
    Last resort- put it in the freezer- get it pretty cold - not freezing- dip one end into warm water- immediately try to separate.
    If this works, wouldn't I be creating another problem with water getting in the lens?

  7. #7

    Join Date
    Feb 2004
    Location
    san jose, ca
    Shooter
    Multi Format
    Posts
    2,550
    Images
    77
    You don't want to do anything with warm water and this lens. I just looked at mine, you just want to put it in the freezer and see if that will allow you to have the play that lets it release. It's a simple thread, male on both outer sections, female in the middle section. Put a pair of gloves on pull it out when it's good and cold and twist.

    You have nothing to lose. You might need the threads chased when you get it apart.

    tim in san jose
    Where ever you are, there you be.

  8. #8
    JBrunner's Avatar
    Join Date
    Dec 2005
    Shooter
    35mm
    Posts
    6,781
    Quote Originally Posted by Sanjay Sen View Post
    If this works, wouldn't I be creating another problem with water getting in the lens?
    If water can get in, it can get out, and as I said, last resort, there being nothing to lose at this point. Tim's advice is more sound, and perhaps water is best avoided in the interest of the balsam, etc. Warming one end with your hand might be a much better procedure. Making one part contract, and one part expand by using temperature is the general idea. Failing any of this, you can borrow my lens hammer. It always works.
    Last edited by JBrunner; 12-09-2007 at 02:24 PM. Click to view previous post history.

  9. #9

    Join Date
    Feb 2004
    Location
    san jose, ca
    Shooter
    Multi Format
    Posts
    2,550
    Images
    77
    Quote Originally Posted by JBrunner View Post
    If water can get in, it can get out, and as I said, last resort, there being nothing to lose at this point. Tim's advice is more sound, and perhaps water is best avoided in the interest of the balsam, etc. Warming one end with your hand might be a much better procedure. Making one part contract, and one part expand by using temperature is the general idea. Failing any of this, you can borrow my lens hammer. It always works.
    J,

    No argument with your procedure, it's just that with a male/female thread in this configuration the heat should go to the center part. That not being possible, just getting it cold should provide enough separation to untwist this thing.

    If that doesn't work, Sanjay Sen I'll give you 10 bucks for the lens, I could use a spare front element. *L*

    tim in san jose
    Where ever you are, there you be.

  10. #10

    Join Date
    Oct 2006
    Location
    Van Buren, Arkansas
    Shooter
    Large Format
    Posts
    2,412
    Images
    101
    He's dealing with a barrel lens here, so a little moisture inside is not catastrophic, as long as it is dried promptly. The only thing inside the barrel is the iris.

Page 1 of 3 123 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin