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Stories of reconstruction, revival and renewal


The story

In this case study we are looking at the split seconds mechanism and how it works.

A chronograph, once operated, tracks the elapsed time – and, between 58 seconds and +1 seconds, will engage the minute register and continuously move it until it flicks over to indicate one minute duration. These counters can be 30 or 45 minutes.

A split seconds allows you to have a second Chrono runner which can be stopped independently – and, once depressed, instantly catches up with the Chrono runner. It could have been invented, for example, when a runner finishes a race. You can stop the split and find out how many seconds behind you were. This is useful information if you need to work on how many seconds you need to improve on. In this example of a pocket watch made around 1880, the split mechanism sits under the watch dial.

Here is a heart-shaped cam – and in this image, you can also see the split pillar wheel and mechanism. The pillar, once depressed, allows the arms to be opened and closed. You will notice a tiny heart-shaped cam in the middle of the movement and  this is fitted by friction to the Chrono runner. This can be positioned in any place on the wheel arbor.

This wheel sits on top of the heart-shaped cam; the spring pushes the lever with the tiny semi-circle jewel and rests against the flat of heart-shaped cam when running together. When the pillar wheel is depressed, the arms close – and, this time, the split wheel will ride around the shape of the heart-shaped cam.

The split is stopped and started by these arms. Both levers and split wheel have fine but unusable meshing teeth that, when stopped, give enough friction to stop the split wheel instantly and prevent any creeping of the split wheel (thus giving a false reading).

In this image, the arms are open and the semi-circle jewel will follow the heart-shaped cam flat and follow the runner.

This image shows hands in place. As the arms are open, the split hands sit underneath the Chrono runner and, in sequence, record the same time together.

This time, the chronograph has run and the split has stopped. The Chrono runner has continued and there is separation. The split hand will not move until depressed, to join the Chrono runner regardless of how many minutes or seconds have passed.

Restoration case studies





What our customers had to say

"My great grand-father's Breguet was given to me by my father for my 21st birthday. 30 years later, post restoration by SHWR, it is in far better shape than I have ever seen it. SHWR's craftsmanship is immaculate. The firm is polite, professional and honest. Outstanding - I cannot recall another occasion when I have been so favourably impressed."


What our customers had to say

"I have just had my 1934 Rolex Oyster repaired. From start to finish I had full confidence in every one I had contact with at Steven Hale. They have been very efficient in identifying the problems at the initial examination and dealing with them as promised. There were no nasty surprises and unexpected complications along the way. Because of the age of my watch, spares are not available, and new parts have had to be made - all very expertly done. They even polished the gold case and my 86yr old watch now looks as good as new. You can certainly trust these people with your precious timepieces."


What our customers had to say

"Fantastic job repairing a family heirloom pocket watch which will now return home to Namibia.
The service was superb with detailed repair and service quote. Communication throughout was equally great leaving you with the confidence that you watch is in the best possible hands."


What our customers had to say

"I had bought a 1970s Pepsi GMT at auction and it needed some work. The lume on the hands was breaking up. Rolex UK wanted some hilarious price and threatened to replace the hands with new ones if their work failed - all at my expense of course. Steven Hale and co managed to repair the hands and maintain the original patina of the 40 plus year old watch which was of course crucial! Highly recommended."


What our customers had to say

"These are watch lovers and it shows. Their meticulous craftsmanship and expertise make them unique in London and I suspect that only in Switzerland may their equivalents be found. The experience of Steven Hale Watch Restoration begins with the talented and charming individuals who are client facing in South Molton Street and who instil a confidence that is consequently fully fulfilled. This firm represents unequalled talent in its field as well as exceptional client service. I have seldom recommended anyone with greater conviction."