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    Re: RAF MK9 Bubble Sextant
    From: Hewitt Schlereth
    Date: 2011 Aug 10, 20:45 -0400
    Sydney -

    I have a Mk IX-A, serial (on back of averager) 14077/42.

    OK Things:
    -Silvering on mirrors is good.
    -Averager works. Runs for two minutes - timed by a stopwatch.
    Dials, knobs and levers feel normal.
    -Counters work normally.

    Things not OK:
    -The lights don't work (Not the bulbs. I checked).
    -5° increment mirror does not shift when lever is actuated
    -Index-mirror arm is so stiff that anti-backlash spring cannot hold its tail-piece against the worm screw for the minutes readout unit. As a result there is 1.5°-1.75° of slop. Makes accurate readings impossible.

    This last is a real bear, because to get at the index arm so you can remove it and clean and re-grease its axle, all the guts of the right-hand half of the sextant have to be taken out.

    I have another MK IX A (11643/42) whose mirrors are not so good and whose averager does not work, and which has the similar stiffness of the index arm. I found I was unable to free up the three screws on the outside of the case that hold the minutes readout unit. To get at the index arm the readout must be removed.  I've decided not to pursue this project further.

    Other than to apply WD-40 to what bearings the WD-40 extension tube could reach, I have not done anything with # 14077/42. (I figured I'd learn on 11643/42. What I learned was - Enough, already!).

    Anyway, if you have the skill and tools or know someone who does, and would like to have this one - 14077/42 - it's yours for what  I paid for it ($25) plus, of course, costs of packaging and shipping it from here in the US Virgin Islands.

    Hewitt Schlereth
    St. John, VI 00830

    On Wed, Aug 10, 2011 at 1:25 AM, Sydney Baderman <sydneybaderman@btinternet.com> wrote:

    I was a navigator during the was and would like to obtain a Mk9. Bubble Sextant. I would be most grateful if you could help. Also interested in aquiring an Astro Compass.

    Sydney Baderman
    Willow Brook
    Hendon Wood Lane
    London NW7 4HR
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