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Stories of reconstruction, revival and renewal


The story

In this case study, we are examining a high-quality perpetual calendar mechanism. This is a unique mechanism - because once it is set, you don’t have to alter the date for 100 years! The mechanism we’re looking at here was in a watch that needed a good cleaning and overhauling to ensure that it ran properly once more – so this presented an excellent opportunity to share with you what goes on inside a watch with this kind of complex and sophisticated mechanism.

This is the date wheel with 31 teeth - and with a steel cam screwed to the wheel. The cam allows the operating lever to drop early and advance the wheel 1,2,3 or 4 teeth, depending on whether it is a shorter month than 31 days , i.e. 30, 29 or 28 days.

This wheel has seven teeth and represents day of the week.

This intermediate wheel also has 31 teeth and connects the date wheel and perpetual wheel. One tooth that is longer than the rest and only comes into contact on the 31st day of the month. This will advance the perpetual wheel one month.

The moon phase has 59 teeth and will revolve once every two months (this is why there are two moons). The dial this is made of gold and is enamelled. The cycle of the moon is 29 and a half days – though it is not possible to make half a tooth. After three months the phase would be out by one-and a-half teeth and would need to be continuously adjusted.

This is an operating lever, and has four functions.

The top claw shape changes the day wheel, whilst the middle claw drops into the perpetual wheel, which rotates close to this claw. The bottom two claws advance the month, whilst the longer of the levers will sit on the month wheel cam and drop early – and if the month is short, this will advance the wheel. The bottom claw will advance the month wheel on the 31st day only.

This is the perpetual wheel with 48 teeth and 48 divisions screwed on top. This rotates once every four years – and  the area circled is for the month of February. There are also three other cut outs at the same depth; the division at the 1 o’clock position is slightly shorter, since it is the 29 days and leap year indicator. Usually, on the dial, there is a  leap year indication - otherwise the calendar would need to be set to every February until the leap year is found. Then, to set the calendar correctly, it would be set from the previous leap year.

Restoration case studies





What our customers had to say

I cannot rate Steven Hale highly enough. From my initial emails, right through to collecting my watch, they were extremely helpful and answered all of my many questions."

"I had my watch serviced and a significant part replaced. I had previously been told by others that the replacement part was no longer available which for a vintage and very sentimental watch was more than a little disappointing. Steven Hale very quickly informed me that this was not correct and they located the part. My watch looks absolutely incredible. It has been serviced before but never come back looking and feeling as good as it does this time. I will always use them from now on and have referred others to them as well."

Rolex datejust - katie r

What our customers had to say

"What a simple, satisfying and reassuring experience!"
A clear outline of the process to begin with, helpful communication along the way and an excellent outcome.The professional approach by the business was enhanced by the individual arrangements made for the transfer of my watch.In all, a really professional experience."

Rolex Oysterdate - Howard W

What our customers had to say

"Incredible restoration of my vintage watch - highly recommend!"
I picked up my 64 year old watch today from Steven Hale after Rolex themselves referred me. I've waited 6 months to be reunited with it (due to it being a vintage), and I am beyond chuffed! I have previously taken the watch to a specialist but was turned away due to its age. But for the first time in years, the experts at Steven Hale have made it work like new. I applaud the excellent team of knowledgeable staff both in the workshop, but also in the showroom, who explained all my options in meticulous detail. This watch has been passed down three generations and I'm so pleased to have it back in full working order. I couldn't recommend Steven Hale enough for anyone with a special vintage watch, unsure of the best place to get it restored."

Vintage Rolex - Oscar S

What our customers had to say

"For years I had been told by a succession of watch repairers that my watch was obsolete, irreparable or both. Finally I was recommended to Steven Hale. Five months later my watch is back on my wrist, as good as it ever was. I can't recommend Steven Hale highly enough."

Vintage Rolex Oyster - Nigel F

What our customers had to say

"Very happy with the communication and service received. Would recommend this company with confidence."

Dr Bakaya

What our customers had to say

"Just to confirm my Rolex has been delivered & looks absolutely spot on. I’d like to express my thanks to yourself & to all at SHWR for the excellent all round professional service - it’s been much appreciated. With your workload backlog I doubt that your Company needs any further recommendations or endorsements, but should you ever want one please don’t hesitate to contact me. With my thanks once again & my best regards."


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

"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."