It’s easy to see why Seikos 6138-0040 is nicknamed the Bullhead. It’s one of Seikos more iconic vintage chronographs and a model I love working on. This particular example came in for a spruce up and service recently.
I’ve featured one of these Scubapro 450 branded 6306’s before but that won’t stop me featuring another! These are so scarce (if you discount the thousands of fake dialled 6309’s you see) that it’s always nice to have a look at the genuine article. This one came in for a movement service recently and as you can see it’s in cracking condition.
I thought I’d feature todays watch because you don’t see too many calibre 8306’s around, this one is in truly fantastic condition and it’s a front loader so I thought I’d explain the different methods available for crystal removal. This watch is branded ‘Business-A’ which was a Seiko JDM marketing campaign in the 60’s and early 70’s to try and make young Japanese businessmen think their life in the cut and thrust world of commerce would only be complete with one of these branded timepieces strapped to their wrist!
I had an unusual request recently, to paint the seconds hand of a watch from red to pink! I asked why the owner wanted this done and he explained the watch was his wifes and that she (and he) had just bought a pink highlighted NATO strap each that were being sold by a guy who’s raising money for breast cancer research. This particular chap and his wife had their world turned upside down 8 weeks after the birth of their first son when she was diagnosed with breast cancer. Out of a feeling of hopelessness that there was little he could do to help his wife he decided to get some NATO straps manufactured and see if he could raise some funds to battle the disease. The story is here along with details of how to order your own strap, and there’s a link to Mikes instagram account here.
Here’s how the watch started….
Seikos professional range of dive watches started in 1968 with the introduction of the 6159-7001, this was a traditional type of divers watch albeit with a monocoque case and was water resistant to 300m. Now the Japanese at this point were excellent at taking design cues from other manufacturers and incorporating them in their own watches, but in 1975 they released the 6159-7010 which was a truly unique and original design of their own. It included several industry firsts, the first titanium case, the L-shaped single crystal gasket and of course the ceramic-coated titanium shroud. With a 600m depth rating, the 6159 dispenses with a helium release valve in part due to very consistent and tight manufacturing tolerances, but also due to the one piece case and screw down crystal retaining system. This means that the crystal cant blow out as atmospheric pressure drops in a decompression chamber as it’s physically restrained by a locking ring. It’s not hard to see how this watch earned the nickname ‘Tuna can’! The watch featured came in for a movement service.
I thought I’d feature this 6138-7000 because it’s a variation of Seikos twin register chronograph that isn’t seen very often. It’s unusual in as much as it has a slide rule bezel and indicator much like the contemporary Breitling Navitimers, although quite how pilots were meant to operate it whilst flying a plane I’m not entirely sure! This example came in for a bit of a smarten up and a full movement service.
I’ve written about Seikos Bell-Matic alarm watches before but I thought I’d feature this one as it’s a complete tour-de-force of problems you can find with a watch! It came in for a service, a spruce up and a relume as the minute hand had lost a small section of lume and the owner wanted it to glow again. I was told it had been running, then it ran intermittently, then it wouldn’t run at all – dirt and debris in the movement or a loose screw rattling around inside perhaps? Time will tell! The watch is a 4006-6040 with a gold dial and contrasting black alarm indicator ring, and arrived on its original bracelet. The first thing I noticed when winding the alarm was that the spring was slipping so that would also need addressing as the alarm wouldn’t sound for as long as it should, needless to say it wasn’t a runner.
Seiko’s Marine Master 300m diver is the direct descendant of the 300m 6159-7001, Seiko’s first professional dive watch released in 1968. The design has changed little over the years, it still utilises a monocoque case and a screw down crystal with a crown at the 4 o’clock position. The original was powered by the high beat 36,000bph calibre 6159a movement whilst it’s grandson uses Seiko’s fantastic calibre 8L35B, which is a 28,800bph, 26 jewel, hacking, handwindable, automatic movement with a date display. This example suffered from a clout against a door frame and the timing went a bit haywire so it was decided whilst the movement was out of the case it may as well have a thorough service.
During the late 1960’s the race to develop the worlds first automatic chronograph had two main contenders, the Zenith-Movado group and a joint effort from Breitling, Hamilton/Bren, Heuer/Leonidas and Dubois-Dpraz. Meanwhile Seiko had quietly been developing the calibre 6138 automatic twin register chrono which was planned to be the first to market and pip the Swiss to the post. Seiko quickly realised the technical challenges of the 6138 wouldn’t be overcome in time to release it as soon as they’d like, so they also developed the 6139 single register automatic chronograph alongside it which neatly side stepped the challenge of getting the hour register chronograph layer sandwiched between the motion work and the calendar components. Because of this decision, in February 1969 the first 6139’s were released to market which pipped Breitling groups calibre 11 official launch on March 3rd. The 6138 challenges were overcome and it was released the following year in 1970. The example featured here is a 6138-0011 more commonly know as the ‘UFO’ although it was originally advertised by Seiko as the ‘Yachtman’. This came in for a movement service and to correct a number of faults amongst which were a chronograph that wouldn’t run for more than 30 seconds and a minute register that reset everywhere but zero! It also came with a number of parts and a replacement case and crystal.
This Seiko Sports 7546-6040 recently came in for some refurbishment, it belonged to the current owners father and hadn’t run for many years. The Sports range of Seikos look like dive watches but are only resistant to 100m and carry a different logo on the caseback, a more stylised wave than the tsunami of the divers watches. This example was in need of a bit of TLC, the crystal needed replacing as well as getting it going again and servicing the movement.