watch parts nomenclature

Basic Mechanical Watch Movement Parts Nomenclature.

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Illustrations by Denis Carignan 2001

1. Train bridge	23. Lower escape wheel pivot / cap jewel
2. Third wheel	24. Escapement inspection holes
3. Upper third wheel pivot / hole jewel	25. Lower pallet arbor pivot / hole jewel
4. Set lever screw (detent screw)	26. Lower balance pivot/ cap jewel
5. Transmission wheel (Crown wheel)	27. Click
6. Ratchet wheel (Winding wheel)	28. Click spring
7. Barrel bridge	29. Upper center wheel pivot / hole jewel
8. Clutch wheel	30. Center wheel
9. Winding pinion	31. Balance cock
10. Set lever	32. Regulator
11. Stem	33. Upper balance pivot / cap jewel
12. Crown	34. Escapement inspection notch
13. Yoke spring	35. Hairspring stud
14. Setting lever spring ( set bridge )	36. Balance wheel
15. Yoke	37. Pallet bridge
16. Upper forth wheel pivot / hole jewel	38. Hairspring
17. Set wheel	39. Upper pallet arbor pivot / hole jewel
18. Lower barrel arbor pivot / hole	40. Pallets
19. Minute wheel	41. Escape wheel
20. Mainspring barrel	42. Upper escape wheel pivot / cap jewel
21. Center shaft and cannon pinion	43. Forth wheel
22. Lower forth wheel pivot / hole jewel	44. Hour wheel