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Posted

Where is a good source for 16S American pocket watxh crowns? And do I buy them by stem size, because the current stem I have is way bigger than a TAP 12, which is 1.2 mm. It's about a 1.8 mm stem.

 

 

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Posted
A quick google and these came up and don't forget ebay. Did you know many of the really old P/W stems only pushed onto want can only be described as a crude typed filed square.
 
http://www.esslinger.com/pocket-watch-crowns/
https://www.cousinsuk.com/category/pocket-watch-crowns
https://www.hswalsh.com/categories/pocket-watch-crowns

The TAP seems to be a bit small on the Walsh crowns. The crown I am replacing had a 1.8 mm diameter on the thread of the stem


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Posted

when un-screwing the crown from a pocket watch case,  heat the crown to prevent breaking the stem.  stems are sometimes hard to find.

Posted

i don't have a "machinst;s  hand book" or a tap chart in front of me ! BUT,  if you have a digital vernier caliper (with switching from metric or S. A. E. readings)  AND a machinist's  thread pitch gauge, you are half way there.    sorry,  often the  existing thread dimension - does not help.  vinn

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Posted
i don't have a "machinst;s  hand book" or a tap chart in front of me ! BUT,  if you have a digital vernier caliper (with switching from metric or S. A. E. readings)  AND a machinist's  thread pitch gauge, you are half way there.    sorry,  often the  existing thread dimension - does not help.  vinn

I do have a digital caliper with mm and in. However, if TAP 12 is 1.2 mm then is there as TAP 1.89?


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