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Thread: Iron ring on brass lens - possible to get off?

  1. #11

    Join Date
    Dec 2001
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    San Joaquin Valley, California
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    9,027

    Re: Iron ring on brass lens - possible to get off?

    If you're tempted to stick the lens in your freezer, here is something to read while you ponder:
    https://www.phrases.org.uk/meanings/...ss-monkey.html
    I steal time at 1/125th of a second, so I don't consider my photography to be Fine Art as much as it is petty larceny.
    I'm not OCD. I'm CDO which is alphabetically correct.

  2. #12

    Join Date
    May 2015
    Location
    SooooCal/LA USA
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    1,953

    Re: Iron ring on brass lens - possible to get off?

    And there's cleaning up the ring, then taking India ink or sharpie to it so it looks like it belongs on the lens... ;-)

    Steve K

  3. #13

    Re: Iron ring on brass lens - possible to get off?

    Put it in a metal working lathe, and turn off the metal you don't want.

  4. #14

    Join Date
    Nov 2017
    Posts
    322

    Re: Iron ring on brass lens - possible to get off?

    Quote Originally Posted by GoodOldNorm View Post
    Put it in a metal working lathe, and turn off the metal you don't want.
    Isn't that a bit dangerous? You have no idea of the form of the brass underneath the iron ring.
    Expert in non-working solutions.

  5. #15

    Re: Iron ring on brass lens - possible to get off?

    Quote Originally Posted by Havoc View Post
    Isn't that a bit dangerous? You have no idea of the form of the brass underneath the iron ring.
    Not really dangerous, a skilled turner can easily work to within 1/1000" . It would be possible to take very fine cuts until the iron and solder was cut away.

  6. #16

    Join Date
    Jul 2008
    Posts
    1,757

    Re: Iron ring on brass lens - possible to get off?

    Much has been focused on removing the iron ring off this lens.

    What are the possibilities the ring was installed for a good reasons. Could it be that the ring was installed to help stabilize the lens and camera during extended photographic film-plate exposure times. A previous owner had difficulty with lens-camera movement, came up with the idea of adding weight to the lens would help, it is quite possible the added weight would help to stabilize and reduce movement during exposure.. which would be helpful rather than destructive.



    Bernice

  7. #17

    Re: Iron ring on brass lens - possible to get off?

    Quote Originally Posted by Bernice Loui View Post
    Much has been focused on removing the iron ring off this lens.

    What are the possibilities the ring was installed for a good reasons. Could it be that the ring was installed to help stabilize the lens and camera during extended photographic film-plate exposure times. A previous owner had difficulty with lens-camera movement, came up with the idea of adding weight to the lens would help, it is quite possible the added weight would help to stabilize and reduce movement during exposure.. which would be helpful rather than destructive.



    Bernice
    Fair point, but if it was mine I would remove all the ferrous metal and replace it with a new brass sleave. I suspect the iron ring may be hiding a split or dent in the original casing. I would use the lens first and see if it was worth spending time and money on.

  8. #18

    Join Date
    Jul 2008
    Posts
    1,757

    Re: Iron ring on brass lens - possible to get off?

    Difficulty to cut this iron ring off in a lathe, are the parts involved round and how much run out does the ID of the ring have -vs- thickness of the solder layer (Verified this is solder?) -vs- run out of the lend barrel.

    Difficulty is not working to 0.001", difficulty is are the parts involved round to 0.001". As for lathe work to 0.0001", not as easy as one believes. Been there done that. It takes a GOOD lathe, highly skilled machinist, GOOD tooling, temperature controlled machine tool area and more to consistently hold 0.0001" on a lathe.

    IMO, if you're going to try for a iron ring removal which is risky on many levels. Remove all the glass elements involved, all heat sensitive parts involved that cannot tolerate extended exposure to 400+ degrees F. Once the lens glass elements and related heat sensitive parts are removed. Put the lens barrel with iron sleeve on a hot plate headed to 450 degrees F. Allow the entire assembly to heat up until the solder is softened, once the solder is softened, slide the iron sleeve away from the lens barrel. All parts involved will be HOT, use caution and tools as needed to accomplish this.

    There will be residual solder on the lens barrel and iron sleeve. Complete solder removal from the lens barrel is not possible without turn-cutting the residual solder off on a lathe.

    Very mess and involved process to remove that iron sleeve.


    Bernice




    Quote Originally Posted by GoodOldNorm View Post
    Not really dangerous, a skilled turner can easily work to within 1/1000" . It would be possible to take very fine cuts until the iron and solder was cut away.

  9. #19

    Re: Iron ring on brass lens - possible to get off?

    If, the lens was worth saving. The rust could be carefully cleaned off with a fine brass wire brush and wet and dry paper. The metal could then be treated with a product called Kurust, then painted or coloured black with Gun Blue paste.

  10. #20

    Join Date
    Jun 2015
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    Anglesey, North Wales, UK [53.3N 4.4W]
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    Re: Iron ring on brass lens - possible to get off?

    Following this thread, it seems that some things are over looked.
    1] Can you determine whether the white material is solder or something else?
    2] Have you tried 'picking' at the material to see if it flakes out or fractures easily.
    3] Can the lens be sufficiently identified, that Steven Tribe can tell what the iron ring covers?
    4] If the iron ring sits on a knurled ring then the white material might have wept into the grooves of the knurling - hence worsening the removal problem.
    5] The capability of the machinist/lathe to work to 1/1000th of an inch is not the issue. The issue is the ability of the machinist/lathe to finely adjust the incremental cutting/shaving depth.
    6] Can the lens be dismantled [from both ends] so that there is less to be [possibly] damaged if and when the iron ring is removed.
    7] Is there any indication that the bore of the iron ring is the same at both ends or is the thickness of the 'annulus' thinner where it is 'joined' to the lens.
    I do not envy you.
    Regards
    Tony

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