RECENT RESTORATIONS

Stories of reconstruction, revival and renewal

SPLIT SECONDS MECHANISM

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

ALL WATCHES REQUIRE A BALANCE STAFF

HIGH QUALITY PERPETUAL CALENDAR MECHANISM

REPAIRING A CLOCK WATCH MOVEMENT

SPLIT SECONDS MECHANISM

What our customers had to say

"Dear Jubal, Yes, Brian texted me yesterday with photos of the clock which he is hugely delighted with – much improved from the original present I gave him! Just like new he said! Thank you for all your courtesy and wonderful work. It has been a pleasure to have such service. I sing your praises everywhere."

Birte

What our customers had to say

"Apologies for the slight delay, but I wanted to thank you for forwarding the Invoice.  I also wanted to tell you that I’m pleased with the watch.  I love the sympathetic polish, which was enough to rejuvenate it, but it still looks appropriate for a vintage watch.  I didn’t notice the metallic blue sweep hand previously, but I like that too..!  Thank you to all who had a part in the transformation Jubal".

Marion

What our customers had to say

"Super to see you and thank you for handing over my father’s Rolex. A great deal of wonderful work has gone into it. It looks utterly super and authentic. I am delighted and I know he will be thrilled when he gets it back on Christmas morning. Thank you for all your efforts and please pass on my appreciation to the workshop who have done a tip top job."

Jeremy

What our customers had to say

"I am so pleased with my watch. I have spoken to many people about the first-rate work of SHWR and will continue to promote you to my friends."

Jane Martin

What our customers had to say

"All in all, the refurbishment has been beyond my own expectations, and allows long term continued use of this almost fifty year old watch gifted by my mother and father.May I personally thank you for your work to refurbish this watch which is very much appreciated."

S L