Wristwatch restoration, servicing and repair

Posts Tagged ‘Memosail’

Memosail Skipper (Valjoux Cal. 7757)…

It’s been quite a while since I’ve written about a sailing timer on the blog. This time it’s a Memosail Skipper.

(Click pictures to enlarge)

The Skipper model differs from the other Memosail timers I’ve written about in the past, as inside is a Valjoux cal. 7757; a sailing timer based on their ubiquitous cal. 7750 automatic chronograph.

There are various sources online claiming that the cal. 7757 was produced between 1985 and 1993, but ETA suggest that the calibre was discontinued in 1988, which probably explains the lack of production watches using this calibre. Apart from the Memosail Skipper, the only other watch I can find that uses the cal. 7757 is the Atlantic Skipper.

According to Juerg K. Bohne, managing director of Atlantic Watch AG, this watch was produced in conjunction with Memotime (the company who produce Memosail watches) and Dubois-Dépraz, the renowned chronograph specialists. He also suggested that in a short production run, just 300 of the Atlantic Skippers were made. I don’t know the number of Memosail Skippers that were produced, but given their rarity, I wouldn’t be surprised if it was a similarly low number.

Let’s have a closer look at the cal. 7757, starting with the components under the dial.

Removing the dial reveals the countdown disc, painted with the white, red, and blue sections that are visible through the holes in dial. The wheel takes 15 minutes to make one complete revolution, and like the cal. 7737 used in the other Memosail timers, it rotates continuously until the timer mechanism is disengaged (for a description of the cal. 7737, see here).

With the countdown disk and timer top plate removed, the heart of the mechanism is uncovered.

Here’s how it works. The driving wheel is mounted on the extended axle of the third wheel in the going train, and provides the power to the countdown disc via the two intermediate wheels. When the timer is started using the start/stop pusher, the detent rotates and simultaneously releases the brake from the gear mounted on the underside of the countdown disc, and using the actuating lever, engages the intermediate wheel with the same gear, and the countdown disc starts to rotate clockwise.

When the timer is stopped the reverse happens, the intermediate wheel is disengaged, and the brake applied to hold the countdown disc steady in it’s current position.

On the train side of the movement, just like a standard cal. 7750, the centre chronograph wheel is engaged when the timer is started, and the centre second hand sweeps around the dial.

There are subtle differences from the standard cal. 7750 though, namely that the minute recording wheel in the 7757 is used solely to perform the reset function, and so has no teeth (see inset). This timer in this calibre doesn’t ‘tick’ forward in 30 second intervals like the cal. 7737, as the timer is driven directly from the wheel train, it is in constant motion when engaged.

When the reset button is pressed, just like a regular 7750, the reset lever moves across to return the reset hammers back to their starting positions. On the dial side of the movement, as the reset wheel is mounted onto the axle of the minute recording wheel, it also returns the countdown disc back to it’s starting position – showing 5 white dots on the dial.

The watch in this post arrived in running condition, but would stop immediately as soon as the timer was engaged. Further investigation revealed that the oil on the timer mechanism had thickened over the years and the increased friction was enough to stop the movement altogether. A full service for the movement immediately put things right.

If anyone has any further information about the cal. 7757, or other examples of watches using the calibre, it would be great to hear from you.

Rich

** Many thanks to Stephen Giles for letting me feature his watch on the blog, and to Mark Reichardt for additional background information about the cal. 7757. **


V.I.P. Memosail (Valjoux Cal. 7737)…

Still in use by a regular sailor this Memosail had one taken one wave too many.

(Click pictures to enlarge)

The owner first noticed condensation appearing inside the watch in May and the watch found its way to me in October. Opening the caseback I was amazed how much rust had developed in such a short amount of time.

The movement inside this watch is a Valjoux cal. 7737 which is modified version of the Valjoux cal. 7733/34. I explained the modifications to the base calibre in a previous post, interested parties can read that post here.

Close inspection of the dial also revealed that the water had got under the edges of the dial paint too.

In some cases, like the Zenith Surf that I wrote about recently, you can get lucky and only the outer parts of the movement are affected, but when the dial is damaged that is a sign that water has made its way right through the watch, and sure enough, digging further into the movement wasn’t a pretty sight.

In cases like this it would be best to order a new part, but specific parts for the cal. 7737 aren’t so easy to find these days, so the only option was to clean up and polish the chronograph heart as much as possible, and repair the pivot using a Jacot tool.

A Jacot tool is used to repair and refinish pivots in clocks and watches. It would be much too long a post to include a detailed description of how it works, but here is a picture of it.

The wheel with the damaged pivot is mounted in the tool and the bow on the left is used to spin the wheel back and forth by hand while working on the pivot with a pivot file or burnisher.

With the rust removed and the rest of the movement serviced, it was back up and running again. The last thing to do was some repair work on the dial. Without a compete repaint it will never be perfect, but the repair isn’t noticeable in daily use.

Rich.

** Many thanks to Richard Littlewood for letting me feature his watch on the blog. **


V.I.P. Memosail (Valjoux Cal. 7737)…

Another sailing timer on the blog, this time from the company Memosail.

(Click pictures to enlarge)

Produced throughout the 1970’s, you can still find a good number of these Memosail timers for sale on the auction sites and forums, which is a testament to their durability and popularity. They were produced in a number of case shapes and styles over the years, a selection of which you can see below.

You may have noticed that some of the dials were marked “Memosail” while others were marked “V.I.P. Memosail”. The significance of the V.I.P. I couldn’t say (apart from the obvious) as mechanically all the watches are identical, and a search on the internet didn’t uncover anything specific.

The Memosail timers are slightly different in operation than the Aquastar sailing timers which I’ve written about in the past. In the Aquastar timers the countdown is signified by a number of coloured dots on the dial which change colour as the countdown progresses. In the Memosail timers a separate disc rotates underneath the dial, counting down from 10 minutes to the start of the race, and rather than being in constant motion like the Aquastars, the disc is only advanced every 30 seconds. The centre second hand rotates constantly around the dial on both watches during the countdown as you would expect.

The Aquastar timers have just one button on the side of the case which is used to start the timer whereas the Memosail is more like a traditional chronograph and has two buttons; the upper button starts and stops the timer, and the lower button performs the reset.

The movement inside the Memosail is a Valjoux Cal. 7737 which is a modified version of the Cal. 7733/4 cam lever chronograph used in many popular chronographs during the 1970’s. While the timer function does it’s job admirably, its design is somewhat simple compared to the mechanics of the Lemania cal. 1345 used in the Aquastar timers (see this post for more details).

With the dial removed you can see the timer ring, the numbers are printed onto the outer edge of a transparent plastic ring which is mounted on a gear that slips over the hour wheel.

Underneath the timer ring you can see the large gear attached to axle of the chronograph minute runner. In a regular 7733/4 movement this axle would extend out onto the dial and the minute sub-register hand would be mounted on it. In a regular 7733/4 a running second subdial is also provided, but as the disc for the sailing timer disc covers the majority of the dial side of the movement that isn’t possible on the cal. 7737.

On the going side of the calibre all the parts are exactly the same as the cal. 7733/4 with the exception of the centre chronograph wheel. Instead of having one chronograph finger to move the register forward every minute, in the 7737 the wheel has two fingers directly opposite each other to move the register forward every 30 seconds.

There was little wrong with the watch in this post except that the timer had been set up incorrectly and didn’t reset to the 10 minute mark. The dial had lost a little of it’s gold ‘sparkle’ too over the years but unfortunately I couldn’t do anything about that. I did however relume the hands while I had it apart which freshened up the cosmetics a little.

Memosail are still produced sailing timers, but just like Aquastar, the mechanical versions of the watches are no longer produced so you’ll have to ‘make do’ with a quartz timer.  If you would like to see their latest offerings you can do that here.

The owner of this watch, Mark Reichardt, has a keen interest in sailing timers. If you have any questions or information about them, especially the vintage mechanical models, I’m sure he’d be interested in hearing from you. You can contact him at the following email address; j.m.reichardt@planet.nl

Rich.

** Many thanks to Mark for letting me feature his watch on the blog. **