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    Re: A-8A Counter disc seized..
    From: Bill Morris
    Date: 2012 Jan 20, 21:00 -0800

    Hello, Eric

    When the averager works normally, you rotate the (outer) vernier disc clockwise until it reaches a stop and its zero should coincide with the zero of the central disc. Adjust the bright metal piece at the bottom right hand corner if necessary to get exact coincidence. This is the starting position.

    If you then set the main counter to, say, sixty degrees and operate the thumb lever back and forth, the zero of the vernier disc should be opposite the sixty of the central disc after eight operations.

    If you carry on operating the lever a few more times, the vernier disc will eventually go through one and a sixth turns and then stop. The thumb lever won't move it any further anti-clockwise, but you should be able to turn it clockwise until it reaches a stop at zero again, ready for the next series.

    If the vernier disc won't move in either direction, remove the two screws in the central disc and remove the disc and th cone spring underneath it. The vernier disc should then lift off the central shaft. If it won't, then give it some releasing oil, rest it overnight and try again. The central disc is a very close fit in the recess in the vernier disc and is best removed by whacking it against the palm of your hand until you can eventually grasp the edge between your finger nails.

    If the thumb lever won't operate, you may have inadvertently reassembled it with its little cone spring trapped between the pin nut and the shaft. It should lie beneath the pin nut and the back of the pentagonal plate.

    If this doesn't make sense to you, Let me know and I will send you some photos of the deconstructed averager off post.


    Bill Morris
    New Zealand
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