Orient Caliber F6F42

Brand	Orient (Seiko/Epson)
Caliber Number	F6F42
In-House?	Yes
Movement Type	Automatic, self-winding mechanical
Jewels	24
Beat Rate /Frequency	21,600 bph / 3 Hz
Lift Angle	Unconfirmed (Add to comments below…)
Power Reserve	~50 hours
Anti-Shock System	Seiko Diashock
Winding System	Magic Lever
Hand Windable?	Yes
Functions	Central hours; central minutes; small seconds at 6:00; power reserve indicator at 12:00; open balance wheel at 9:00
Hacking Seconds?	Yes
Country of Manufacture	Made in Japan
Known Models	Orient Star Mechanical Classic Watch (Ref: RE-AV0007S, RE-AV0001S, RE-AV0002S) (Please add your watch and more known models to the comments below…)

Orient caliber F6F42 is a self-winding automatic movement with a power reserve indicator at 12:00. Other notable features of this movement is the open balance wheel (aka “open heart” or skeletonized balance wheel) at 9:00 and small seconds indicator at 6:00.

As a member of the F6F4 family of Orient watch movements, the F6F42 does not have a calendar complication. Furthermore, it is a true no-date movement with only two crown positions: against the case (position 1) and pulled out one click to time-setting mode (position 2).

Orient makes their calibers in-house in Japan. The F6F42 is an evolution movement with up upgraded power reserve to 50 hours on a full wind. This calibre also includes popular functionality including the ability to manually wind the movement, as well as hacking seconds (Orient refers to this as a second hand halt mechanism).

Accuracy:

Orient claims that the accuracy of the caliber F6F42 averages between +25 / -15 seconds per day.

F6F42 VS F6R42:

There is a similar Orient caliber F6R42 with the main difference being that the “R” version has a central seconds hand, while the “F” has a small seconds subdial just above the 6:00 hour marker.

Examples of watches with this movement:

Additional Resources:

• Official instruction manual (pdf)
• How to locate Orient caliber numbers
• List of Orient calibers