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Learn all about Seiko service intervals here. How often does the 6R64 need serviced?Īccording to official Seiko documentation, watches with the caliber 6R64 should be overhauled every 2-3 years. In that case, the hand may advance anywhere between 9:00PM and 3:00AM, so do not be alarmed if you see this difference in date flipping. This span changes when you are advancing the date manually by turning the crown.
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According to Seiko documentation, the date hand should advance between 11:45PM and 12:30AM, while the watch is running normally. The 6R64 has a date hand at 6:00 rather than a traditional calendar window. To avoid damaging your watch movement, do not adjust the date when the hands are set between 9:00 PM and 3:00 AM. Seiko recommends going in the direction that is nearest to your desired date, presumably so that you put less wear and tear on the gears and setting mechanisms. It is ok to go clockwise or counterclockwise to set the calendar forwards or backwards. When the crown is pulled out one click (position 1), you can rotate the crown forwards or backwards to advance the hours, which will change the date when you pass midnight in either direction. The date on the 6R64 is set with the hour hand.
SEIKO SPB 221 MANUAL
0 (against the case): Clockwise = Manual Winding / Counterclockwise = Nothing.
SEIKO SPB 221 FULL
Wearing the 9R65 powered watch for 12 hours/day over the span of 3-5 days will get the movement to full power reserve. It is recommended that when winding the crown, the rotations are made slowly. Winding backwards or counterclockwise will do nothing. The crown winding direction is clockwise, or forwards. The caliber 6R64 holds a power reserve of at least 45 hours.Īccording to Seiko, it only takes five full rotations of the crown to power the watch to run for about 10 hours. “Due to the characteristics of mechanical watches, any actual daily rate may not fall within the range of time accuracy specified above dependent on the conditions of use, such as the length of time during which the watch is worn on the wrist, temperature, arm movement, and whether the mainspring is wound up fully or not, etc.” – source Power Reserve: Seiko officially claims this movement is capable of an average daily rate of +25 to -15 seconds per day in normal temperature conditions (between 5 – 35 degrees C). The Seiko caliber 6R64 is adjusted/regulated at the factory. As of this post, there is only a caliber 6R64A (which is the same as 6R64). The subsequent letter variations indicate evolution in the movements development. The general caliber number is 6R64, with 6R64 A being the first version. The date is shown on a sub-dial at the six o’clock position and there is a power reserve indicator at nine o’clock.” – source The dial rings are in two colors to separate the night and day hours at a glance. The GMT hand can also be used as a dual time indicator, with the hour hand being adjustable even as the minute and seconds hands continue to mark time. The GMT hand on each is in a different color to stand out clearly from each dial and, like the hands and indexes, has a generous layer of Lumibrite, to ensure legibility. All four watches are powered by the eight beat-per-second GMT Caliber 6R64.
SEIKO SPB 221 SERIES
This caliber is found in the Presage Sharp Edged Series GMT lineup that was announced on February 24, 2021. The Seiko caliber 6R64 is an automatic GMT movement with a date subdial and power reserve indicator. Seiko Presage Sharp Edged Series GMT: SPB217 (SPB217J1), SPB219 (SPB219J1), SPB221 (SPB221J1), SPB225 (SPB225J1) (Talk about your watch in the comments below…) Central hours, central minutes, central sweeping seconds hand, central GMT hand (second time zone), date subdial at 6:00, power reserve indicator at 9:00