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Surprising Calibres of Naoya Hida
Naoya Hida & Co. is an independent watch atelier in Tokyo producing a small number of classically-inspired watches in annual batches. As discussed in my recent blog post, Naoya Hida has introduced three models since 2019. Each model uses a customized movement based on the ETA 7750 automatic chronograph ebauche, a surprising choice because Hida’s watches are neither automatic nor chronographs! This being Grail Watch, I spent a good amount of time digging into the Hida calibres and am documenting them here on Grail Watch Reference.
The NH Cal. 30 Family
All three Hida movements to date have a similar appearance, and all are based on the 7750 ebauche, wheel train, barrel, balance, and escapement. The small seconds and moon phase movements likely share the same balance bridge and plate, and both feature 18 jewels.
The central seconds hand on Cal. 3020CS is driven using a rear-mounted wheel, requiring a secondary plate at the center. It also features four extra jewels, for a total of 22.
Cal. 3021LU, used in the Type 3, uses the moon phase mechanism from ETA’s Cal. 7751 but omits a seconds display entirely. Like Cal. 7751, the moon phase indicator is adjusted with the crown in position 2.
https://reference.grail-watch.com/2022/ ... aoya-hida/
The NH Cal. 30 Family
All three Hida movements to date have a similar appearance, and all are based on the 7750 ebauche, wheel train, barrel, balance, and escapement. The small seconds and moon phase movements likely share the same balance bridge and plate, and both feature 18 jewels.
The central seconds hand on Cal. 3020CS is driven using a rear-mounted wheel, requiring a secondary plate at the center. It also features four extra jewels, for a total of 22.
Cal. 3021LU, used in the Type 3, uses the moon phase mechanism from ETA’s Cal. 7751 but omits a seconds display entirely. Like Cal. 7751, the moon phase indicator is adjusted with the crown in position 2.
https://reference.grail-watch.com/2022/ ... aoya-hida/

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