This Sinn 103 chronograph came in for a problem with the crown to be sorted, only a small job really but as you don’t see these very often and it’s such a gorgeous Bundeswher type chronograph it would be a sinn not to show it (geddit?)!
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.
Omegas Speedmaster watches have to be one of the most iconic chronographs that have ever been made. From it’s introduction in 1957 to the present day the design has changed very little, an original CK2913 speedy is still undoubtably related to every model that came later. The movement changed throughout the years starting with the column wheel calibre 321, in 1968 the cam lever calibre 861 was introduced and in 1977 some small modifications were made and it became the calibre 1861. In more modern times movements based on the F. Piguet 33xx and the Omega calibre 9300 have been utilised. Of course the Speedmaster shot to fame with NASA choosing it as their official watch certified for space flight in 1965, and it was taken to the moon on a number of occasions. This fact is celebrated on the back of Speedmasters produced since then with the legend ‘First Watch Worn on the Moon’ engraved on the back. This 1977 example came in for a movement service, it was also suffering from a fluttering seconds hand and chrono creep on the hour register.
Another JDM Sports Seiko for your delight today! This one is known as the ‘Basketball’ due to the fact it was designed to time basketball and football (soccer) matches with its graduated rotating inner bezel. I can only guess it was designed for college basketball games as they have two 20 minute halves and the inner ring on this is graduated in two yellow 20 minute sections with a ten minute break in between. The soccer section of the ring is marked in white blocks for 45 minutes, the time for each half of a game. It’s powered by the calibre 7017a movement which is an automatic, 21 jewel, 21,600bph, day/date movement with a flyback chronograph feature. The way to time something using this is to line up the inner ring with the minute hand then start the chronograph running, you can then read off the elapsed minutes against the basketball or soccer timer. Flyback means you can reset the seconds counter to zero without actually stopping the chronograph from running. This example arrived in a non running state, the date wouldn’t set and the chrono seconds hand wouldn’t move or reset.
I’ve featured Seikos 6139-600x series chronographs before but never a blue dialled one! I thought this may be of interest as it’s suffered from quite a common problem whereby the minute counter doesn’t count or reset properly. This example came in needing a service and the minute register problem sorting. The photographs I took at the start didn’t come out for some reason (I think I probably deleted them by pressing the wrong button!) so we’ll start with the caseback removed. The movement looks in reasonable shape but the trace on the timegrapher was appalling so it was definitely in need of a service
The Poljot Calibre 3133 is a 23 jewel, 21,600bph, cam controlled, manual wind chronograph with a coulisse lever system. It has running seconds at the 9 o’clock sub register, minutes elapsed at 3 o’clock and a central sweep seconds counter, it also has a date a 6 o’clock. In the 1970s, the Russian Poljot factory purchased the machinery to produce the 3133 from the Swiss firm Valjoux , at that time they were disposing of the machinery that once produced their chronograph caliber 7734. Poljot then used this to produce the 31mm calibre 3133. A good proportion of the parts of the Poljot 3133 are identical to the Valjoux 7734. The main differences between the two calibres are that the Poljot has all chronograph related gears running in jewels, and the glucydur balance swings in a Poljot developed shock protection system. The balance was modified to a smaller diameter which makes the 3133 run at 21,600bph compared to the 7734’s 18.000bph. This example has an inner 12 hour bezel that can be rotated by the crown on the left of the case and it came in for attention in a non running state.
A sticky pusher or two is not an uncommon occurrence on Omega Speedmasters. This can be caused by a build up of crud inside the pusher tube if the seal has failed but more usually the cause is a broken spring. I thought I’d show how I approach this repair.