Grand Seiko 6146-8000 Late Model, 10-Beat, Automatic, Overhauled, Manufactured in 1968 (Showa 43)

This is a 1968 "61 Grand Seiko (Ref. 6146-8000)."

The 61 Grand Seiko, introduced in 1967, was the first Japanese-made wristwatch with a 10-beat automatic movement.
It is equipped with a next-generation automatic winding mechanism that successfully adapted Seiko's proprietary "Magic Lever" ratcheting system to a high-frequency rate of 36,000 vibrations per hour.
This is a highly practical day-date model featuring a hack function (second-hand stop), a quick-set date, day-of-the-week adjustment via hand manipulation, and manual winding.
The rotor surface features a "rippled" finish, and other components are also meticulously polished, conveying the dignity characteristic of Grand Seiko timepieces from that era.

The ratcheting "Magic Lever" is a mechanism that winds the mainspring by converting the rotational movement of the rotor into the reciprocating motion of a lever (pawl).
Compared to systems that wind via gear trains, it is characterized by higher winding efficiency.
Because it has fewer parts, it is also highly durable, making it an excellent mechanism that many manufacturers have adopted in recent years.

This particular unit features "HI-BEAT 36000" engraved at the 6 o'clock position on the dial.
The engraving on the automatic rotor reads "SEIKO".
The gold medallion on the case back, featuring the "GS" and "Suwa" marks, remains in beautiful condition.

Condition

This watch has been overhauled and the exterior has been refinished.
Crown operation is smooth, and the automatic rotor functions correctly.
Please enjoy the unique manual winding feel and rotor sound of the 61GS, which offer a mechanical charm exclusive to the high-beat & Magic Lever combination.

The case retains the sharp edge lines unique to the 8000 series, maintaining wonderful condition without any thinning due to excessive polishing.
The crown is a valuable genuine part featuring the GS mark, with clear engravings.
The crystal is clear with no noticeable scratches, ensuring good visibility.
While light vintage-typical aging is visible around the calendar and the edges of the dial, it is not noticeable to the naked eye and does not detract from the overall beautiful atmosphere or the brilliance of the hands and indices.

The strap has been replaced with a brand-new genuine Seiko leather strap, ensuring comfortable wear.

As this is a vintage watch, it is not water-resistant. Usage in environments with moisture (such as on rainy days, while washing your face, or wearing it on hot, sweaty days) is strictly prohibited.
As this is a precision instrument, please be careful to avoid drops and strong impacts.
Also, please be careful not to bring it near items that emit strong magnetic fields, such as smartphones, PCs, or bag clasps.

Operation Instructions

Manual Winding: Rotate clockwise with the crown in the standard position

Pulling the Crown: Gently pull the crown out by inserting a fingernail between the case and the crown

If the crown is pulled with too much force, there is a risk of it coming out; please pull it out gently.
To prevent bending the crown, remove the watch from your wrist before operation.
Operating it gently reduces the strain on the crown.

Quick-Set Date: Rotate clockwise with the crown pulled out to the first click

The movement may be damaged if the quick-set operation is performed while the time is set between 9:00 PM and 3:00 AM.
We recommend setting the time to around 6 o'clock before performing the quick-set.

Time Setting: Rotate counter-clockwise with the crown pulled out to the second click

The second hand will stop when the crown is pulled to the second click (hack function).

Day Adjustment (via hand manipulation): Move the hands back and forth between "10:30 PM and 1:15 AM" with the crown in the second click position

1) Move the hands forward until midnight (12:00 AM).
If the day begins to change, it is midnight. If it does not, it is 12:00 PM.

2) Move the hands forward to 1:15 AM to advance the day. Then, move the hands back to 10:30 PM.
This prepares the calendar to show the next day. (When moving the hands backward, the display will show FRI→FRI, etc.)

3) Advance the hands to 1:15 AM.
Confirm that the day has advanced by one.

By repeating this process, you can advance the day one by one.
Please operate slowly to reduce the burden on the movement.