The Grandfather Tuna as it was affectionately known was the first ISO rated professional dive watch by Seiko. Released in 1975, this timepiece was developed specifically for saturation diving. The model introduced a number of key developments to the market; including removing the requirement of a helium escape valve by using an L shaped gasket in the case design, and the expandable rubber dive strap that is still used today on the Prospex range of watches.
In 2000, Seiko released a limited run of 1,000 recreation models called the SBDX005, which reach around $10,000 NZD if they can be sourced. Original examples of the 6159 are around $7,000 NZD, and the range is still being developed today with the SRP Prospex Tuna lineup.
I have set to recreate this legendary Seiko timepiece using modern technology with the Time Design Grandfather Tuna.
The 6159 compared with the now 20 year old SBDX005 recreation
Photos from Worn & Wound
Parts: - 316L PVD black stainless steel recreation case including black steel shroud - Domed sapphire crystal - Vintage-esque aluminium chapter ring - 20mm recreation 'waffle' rubber dive strap - Seiko Tuna handset - 300m sunburst black dial - Seiko NH35 automatic movement - Coin edge bezel
The 6159 showing signs of age pictured by Fratello Watches
The SBBN011 "Darth Tuna" modern range of Seiko Prospex Tunas pictured from Worn & Wound