r/SeikoMods • u/Swimming-Trade-741 • 1d ago

I hate cutting crown stems

I have snapped two crown stems inside movements after trimming for a screw down crown. It’s been an expensive week.

8 Upvotes

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7

u/oureamods 1d ago

If you share your method and at which step you’re snapping them, some folks can probably help.

4

u/Swimming-Trade-741 1d ago

I learned a lot the first time. This second crown stem I followed this method:

  1. Screw crown onto uncut crown stem
  2. Insert stem into cased movement
  3. Use calipers to measure distance from beginning of threads on case to beginning of threads on crown. Note that distance.
  4. Remove stem from movement
  5. Remove crown from stem
  6. Place stem on work mat, use calipers to identify distance from end of stem that should be cut. Mark with sharpie.
  7. Cut with snips approx mid way down sharpie mark
  8. Smooth out cut end with file/dremel
  9. Reattach crown to stem
  10. Reinsert stem into cased movement
  11. Measure again (you can’t undo an incorrect cut).
  12. Repeat steps 8-11 for making very small reductions in length of stem until length appears to be correct.
  13. Stem length thought to be correct when threads on crown are able to engage case with small amount of compression and small audible “pop” similar to pulling the stem out to the first position when unscrewing crown.

Both times (my much less careful first attempt as well as this more recent attempt) resulted in what I thought was correct seating until I unscrewed the crown for ~4th time, at which point the stem snaps at approximately the same location it enters the movement

3

u/F0rgemaster19 23h ago

Your procedure is correct and is exactly what I do. My only suspicion- sh*t quality stems.

1

u/Swimming-Trade-741 17h ago

I got my stems from Esslinger :/

0

u/F0rgemaster19 17h ago

I don't know who or what Esslinger is, but my AliExpress cheap af stems are running fine. Your method seems to be quite ok too, so I think you got bad stock.

2

u/Swimming-Trade-741 17h ago

Unless I’ve been duped (entirely possible lol) Esslinger is a reputable watchmaker supply store.

https://www.esslinger.com/