WS 19: Servicing a SEIKO Chronograph 6138

The stem that was in the watch is in the background. Luckily Rob has quite a few spare parts for this movements ready. Thus finding a correct stem was not including a travel to the watch parts shop. To the watch graveyard actually, since spare parts for these movements are harder and harder to get. You can clearly see that the dimensions and the position of the collet are not to the same. But this movement - unlike many movements found in Bangkok - was in very good condition and was not puzzled together from countless other movements.
The square part of the new stem needed some fine strokes on the diamond dust board, but this turned out to be a tuning requirements much later to be detected when replacing of the hands. Rob also filed down the length of new stem from 3.45 mm (distance above case stem tube) to 3.15 mm. A couple of find strokes again on the diamond board and that 0.25 mm was removed.

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