Zodiac Astrographic SST (Zodiac Cal. 88D)…

I don’t mind the odd eBay gamble, but this Zodiac Astrographic SST was a real punt.

(Click pictures to enlarge)

The watch arrived complete but in decidedly average condition and showing no signs of life. It couldn’t be wound either via the crown or the automatic winding mechanism, and the crown and stem pulled straight out of the watch – not the best of starts.

Zodiac first introduced the Astrographic SST in 1969, and as this early advertisement shows they were initially available in two case styles, the square cased model in this post, and a round cased version – the smaller versions are of course ladies models.

Gold plated models were added a few years later, and so was the “Astrodigit”, a further development of the concept which displayed an additional ‘digital’ readout of the time in the centre of the dial.

As you may have noticed, the unique selling point of these watches is that the time is displayed as “floating” batons for the hours and minutes, and an orbiting red dot for the seconds… very 1970’s.

With the watch removed from the case you can see that the floating effect is created by using three transparent discs in place of regular hands, each one visible through the next. Inset you can see the individual discs and dial.

The movement inside is a Zodiac cal. 88D which was derived from the manually wound A. Schild cal. 1687/88 and was specially modified for the Astrographic watches as extra height was needed on the dial side to accommodate the discs. The cal. 88D is one of the high beat calibres found in all of Zodiac’s SST (Split Second Timing) models. It runs at 36,000 bph or 10 beats/second, which as well as other technical advantages, gives the red seconds dot a smooth sweeping action around the dial.

On disassembling the watch I found that two parts in the automatic winding mechanism were damaged, but I had a parts movement from a previous Zodiac SST project that provided all parts required, so the problems were quickly solved, and after a service the movement was up and running again.

Cosmetically the watch was in poor shape too. The case had seen its fair share of ‘action’, and as you can see in the picture below, the crystal was pretty badly scratched.

Replacing non-round crystals isn’t straight forward, but for this watch it is even more difficult as the minute track and Zodiac symbol are transfer printed onto the underside of the glass, meaning that a genuine Zodiac replacement crystal would be needed, but they are long discontinued.

I did eventually track down a genuine crystal in the US, but with shipping costs factored in, the overall price was more than I’d paid for the watch, so I thought I’d try to polish out the scratches instead – not a simple process for mineral glass.

Increasingly finer grades of emery/polishing paper are used to remove the scratches and the final finish is achieved with a damp felt mop charged with cerium oxide. That process generates a lot of heat, and I was afraid that the transfers would melt, so I completed the whole process by hand. Considering how much time the entire polishing process took, I wouldn’t recommend it unless you’ve got endless patience!

With the major marks removed from the case and after a re-brush, the watch was finally rebuilt. It still has its original Zodiac signed bracelet too which is a bonus.

Rich.