The Watch Site banner

1 - 4 of 4 Posts

·
Registered
Joined
·
82 Posts
Discussion Starter #1 (Edited)
GRANDFATHER TUNA

MODEL - YAQ028
CALIBER - REFERENCE - 6159‐7010

MARKET - JAPAN
PRODUCTION 1975-1978


MODEL - 60257
CALIBER - REFERENCE - 6159‐7019
MARKET - EXPORT
PRODUCTION - 1975-1978


SEIKO RETAIL - ¥89,000
MARKET VALUE - $1800 - $3000+
CALIBER - 6159B Automatic
JEWELS - 25
BPH - 36,000 (10 beats per sec.)
POWER RESERVE - 48 hours
DIAMETER - 50.5mm
LUG-TO-LUG - 52.2mm
THICKNESS - 15.9mm
WEIGHT - 93g
LUG WIDTH - 22mm
STRAP - XGL801 - GL801 / BUCKLE - Ti
WATER RESISTANCE - 600m / 1968ft.
CASE - Titanium
CASE TYPE - Monocoque
CRYSTAL - Flat Hardlex
CRYSTAL - Part # 335W08GA00
DATE WHEEL - Numeral
BEZEL - Titanium
BEZEL INSERT - Acrylic
SHROUD - Titanium
SHROUD COATING - Ceramic
SCREWS - Titanium
SCREW HEAD - Full Cross

- YAQ028 6159-7010 was the world’s first titanium diving watch and SEIKO’s first auto Tuna.
- YAQ028 6159-7010 took Ikuo Tokunaga and his team of SEIKO engineers seven years to develop and build.
- YAQ028 6159-7010 had 23 watch industry firsts, including the L-shaped crystal gasket, two-layer case and accordion urethane strap.
- YAQ028 6159-7010 exceeded strict ISO testing standards by being highly pressure and shock resistant (up to 10 Gs). It also prevented helium gas penetration and had the ability to withstand extreme temperatures and high degrees of magnetism (60 Gauss).
- YAQ028 6159-7010 dials from early 1975 show ‘PROFESSIONAL 600’ in white text, with the SEIKO Suwa logo below and dial code: 6159 -7010T.
- YAQ028 6159-7010 dials changed late in 1975, an ‘m’ was added to ‘PROFESSIONAL 600(m)’, with dial code: 6159 -7011T.
- 6159-7019 dials are identical to late 1975 6159-7010 dials, with same 7011T dial code. Early 6159-7019 non-m dials likely do not exist.
- 6159-7010/19 were re-issued and faithfully re-mastered as SBDX005 8L35-0030, part of the ‘Seiko Historical Collection The Year 2000’.
- The ‘Grandfather Tuna’ may also be known by the nickname ‘Hockey Puck’.
- SEIKO has preserved this basic design concept for all its monocoque cased professional 1000m Tunas that are still being produced to this day.
 

Attachments

·
Registered
Joined
·
82 Posts
Discussion Starter #4

Attachments

1 - 4 of 4 Posts
Top