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    Re: A-8A Counter disc seized..
    From: Eric van der Veen
    Date: 2012 Jan 21, 11:46 +0100

    Hello Bill, nice to meet you now through this channel.
    
    This makes perfect sense. The outer disc indeed won't move. I had
    trouble removing the centre disc, and whacking it didn't come close to
    bringing it off. In the end I managed to get it out by making a small
    tool from iron wire to pull it out from the two screw holes. I removed
    the cone spring. So I'm ready for the releasing oil.....    now what
    exactly is releasing oil to you? Would penetrating oil like WD-40  be
    OK? And then is the outer disc freely attached to the central shaft or
    screwed or otherwise?
    
    The lever operates OK and I did not disassemble it. I only briefly
    disassembled the locking nut and cup spring on the underside of the
    averager.
    
    Eric
    
    
    
    Op 21-1-2012 6:00, Bill Morris schreef:
    >
    > 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.
    >
    > Kindregards
    >
    > Bill Morris
    > Pukenui
    > New Zealand
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