Carriage Clock Repair and Service Process
I was recently brought an old family heirloom which had sat unused in a cupboard for many years. I had restored a longcase clock for the client which made them of this clock they had inherited some time ago. It belonged to their grandparents and brought back memories of their childhood.
Here are some before images, as you can see it was looking a bit tired. Repeated polishing with brasso had taken away the original guilt surface, and revealed the brass underneath which has tarnished. Additionally, the dried polishing compound eventually breaks up into a powder which has clearly got into the movement.
The Movement Service
First and foremost to any work I do is the service/overhaul to the movement. Addressing wear and tear as well as a thorough clean is imperative for a clock to run well. Occasionally this means fixing poor quality repairs that have been done before, too. Here you can see three pivot holes which are too loose and require bushing. On one, you will notice a dent which is a quick (and unsatisfactory) method to temporarily try and tighten the hole which was done by a previous repairer with a punch. It’s a very poor repair which is sadly a common sight.
Clock Plate Bushing
The proper way to fix this wear is to fit a bush, a donut of new brass which returns the hole to the size it should be. This takes care and skill to do properly, ensuring the bush is properly centred and the correct size, while keeping the bush as small as possible to try and keep it invisible. The better the quality of repair, the less you will know that any work has been done. Personally, I fit a bush that is over length with an under sized hole, which allows me to make adjustments to ensure everything is perfect once the work is complete. Below is an in progress image, then two completed bushes with the wheels installed - a perfect fit and almost completely invisible.
Bushing ensures that the pivots have as little friction as possible, and the meshing of wheels and pinions are at the correct depth meaning power transfer is efficient - it’s very likely an unbushed (or badly bushed) clock won’t run and this is one of the most common reasons a clock will stop.
Mainspring Repair
This particular clock has only one mainspring as it is time only. Every spring needs to be removed from its barrel to thoroughly clean it but also to carefully check for any wear or damage. This spring has developed a very small crack at the outer hooking. If left unchecked, this crack can grow and lead to a broken mainspring which can severely damage the clock or worse: the owner. The usual repair for this involved cutting off the damaged hooking and making a new one, this reduces the length of the mainspring fractionally but not enough to change the running of the time any noticeable amount. The hardened spring steel is softened with a flame, then a new hole is cut centrally and hand filed to a suitable shape.
When repairing clocks and watches details matter and show how much care the horologist has given. And easy way to judge standards is to look at the taper pins holding the clock together. Are the bent? Have they been left at their orignal length or cut down to fit? If they’ve been cut down can you see the cutter marks?
Wherever possible I cut all taper pins to a neat length, and finish the ends to make them look tidy. None of this makes any difference to how the clock runs, but why let your standards slip at any point in the process?
Case Refurbishment
The Client requested that the case be brightened somewhat, but really didn’t want it polished or gold plated; it was important that the clock still showed its age after the work was complete. to achieve this the case was carefully cleaned a bit at a time to slowly remove the oxidisation to a level which I thought was a good balance between presentable and aged. then a clear laquer was carefully applied to protect the metal and prevent further tarnishing. It’s amazing the difference a good clean can make - not everything has to be polished to within an inch of its life!