Hope this helps !

[digginstony]

I've been working on cheap Chinese movements lately and other movement's mainly studying different types and auto winds.

This rotor is secured by 2 little screws and the 1 by the balance is so easy to drop into the mechanism and ends up lodged in the escapement wheel. Twice this has happened to me, even holding it with tweezers whilst trying to screw down. Now I put a bit of tape over the area incase I slip. See photo.

 

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[canthus]

Re your interest in auto-winds, have you had a look at an AS1701(mid 1960's vintage).   This has a ratchet system on the bottom of the barrel arbor which connects to the auto-wind gear train via a wheel with a matching ratchet.  Just been working on one, and this ratchet wears if hand-winding is done frequently making the auto-wind non-fuctional as well as wearing the raised land on the main-plate ! New parts are no longer available and used are likely to be in similar condition and all are quite expensive relatively.  Still works as a manual wind though !!

3903_AS 1700, 1701_Smaller.pdf

[digginstony]

Re your interest in auto-winds, have you had a look at an AS1701(mid 1960's vintage).   This has a ratchet system on the bottom of the barrel arbor which connects to the auto-wind gear train via a wheel with a matching ratchet.  Just been working on one, and this ratchet wears if hand-winding is done frequently making the auto-wind non-fuctional as well as wearing the raised land on the main-plate ! New parts are no longer available and used are likely to be in similar condition and all are quite expensive relatively.  Still works as a manual wind though !!
3903_AS 1700, 1701_Smaller.pdf

Will take a look. Many thanks

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[vinn3]

are you sure that manual wind is distructive to the auto wind mechanism?  vin

[canthus]

It would appear so. The keen edges of the lower ratchet wheel and barrel arbor pawls have gone and this allows them to slip.  I tried shimming-up to get tighter mesh but it still slipped. New parts are not readily available or too expensive (and used parts or donor movement may have been in same condition) so I gave up as the cost would not be justified re rest of watch etc.  This wear could have been a result of wear on the main-plate (there was a raised ridge originally which the lower ratchet wheel ran) and then also on the barrel bridge causing the auto-wind to not work and then the owner continuously hand winding.  I did service it and it runs ok as long as it is manually wound daily.