Most stem-setting vintage American watches are “negative setting” meaning that the snap action of the crown is actually a function of the case. The neck of the case includes a sleeve spring and a stem. The crown threads onto the stem. pulling the crown out snaps over a shoulder in the stem over the fingers of the sleeve, and the watch pushes the stem out, going into setting mode.
For this to work, the inward position has to leave the stem far enough into the movement to engage winding, but not too far, while the outward position has to engage setting. The crown has to fit over the neck of the case and under to bow. And the threads on the stem have to match the crown, as the square end has to match the movement. The sleeve is threaded into the neck so its depth can be adjusted but that’s it. None of this is standardized. American watch companies in general did not made cases. People bought cases separately and retail watchmakers fit the movement in. It’s not unusual for stems to be hand made.
Finding these parts is getting really difficult.
This watch came to me without a crown, and the threads on the stem are stripped. I could not find a perfect match to replace the stem but I found one close. Using the lathe and other tools I modified the replacement to work. The part prior to modification is shown here.
Find out more about pocketwatch cases, and positive and negative setting systems here.
Of course I leave out all the gory details in these posts. This took quite awhile. I broke the first candidate stem while just finishing it up, and had to hunt for another close match. Very frustrating…
See the complete album for this project here.
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