Antique and Vintage Mechanical Clocks

This unnamed fusee clock was acquired from a friend this past summer and after a few months, I am finally able to hang it on the wall. Unfortunately, after having been involved in the extensive cleanup following the devastating hurricane Fiona here in Nova Scotia, there was little time for clock repair. But, now that the dust has settled it’s time to get back to clock collecting and repair.

It is the first fusee clock in my collection. I have waited a while but this is an excellent acquisition.

This time-only gallery-style clock with a fusee movement is non-descript and quite ordinary and there is nothing special or distinctive about it. It has a 12″ dial and is 15 1/2″ across with a spade hour hand and spear minute hand with a heavy brass dial bezel.

A 12-inch dial is considered the standard size for a gallery clock and a 12-inch dial would have been the maximum size for a domestic environment. Larger 14″ and 16″-inch” gallery clocks would have been found in public areas, factories, and post offices.

I am not an expert when it comes to identifying wood types but I would say a solid mahogany bezel surround with veneers on the rear access box.

Although fairly heavy it is designed to be quickly removed from the wall by pulling out 4 wooden pegs (two on each side of the back box), very handy for periodic inspection/maintenance. The pendulum leader literally hangs on a notch on top of the escapement bridge so, disconnecting by means of opening up a side door on the right and reaching in is pretty simple.

It has a conventional anchor escapement, a robust bridge, and a sturdy crutch. The plates are held together with screws but pinned to the back of the dial.

There is a trademark on the movement which I cannot identify. Perhaps a reader might identify this English company. I can make out T, an S, an O, and something else. Atson, AT & Son or something with a “z”?

I posted the question on a popular antique clock forum site and expected a response but got nothing.

Is it an antique (over 100 years old)? Perhaps, but it could be as late as the 1920s. The plates are thick, the gears are machine cut, cut pinions throughout, a hefty pendulum bob, thick but plain movement pillars, and a generally robust feel all around. It was certainly designed for longevity and reliability. The screwed pillars are a good sign that it was made after 1900.

This fusee has a cable drive. It is unknown whether it originally had a chain as most did many years ago or if it was converted to cable as many were when taken in for servicing. Chains are difficult to source and wire/cable is much more cost-effective.

An advantage of a brass cable is that if it should snap there would be less collateral damage than a chain flailing all over the place. When a chain releases very suddenly the potential for taking out gear teeth and other parts is much higher.

Fusee advantages

Constant torque and in theory, more accurate timekeeping are its chief advantages. It works like this. As the spring begins to uncoil the cable is on the smallest diameter of the fusee. The pull on the spring drum becomes less as the diameter of the fusee increases. The diameter of the fusee becomes larger giving greater leverage.

The larger radius at the fusee compensates for the weaker force of the spring, keeping the drive torque constant which is why fusee clocks are better timekeepers than conventional spring clocks.

Accuracy cannot be compared to a quartz clock today but keeping time within a minute or two a week in an industrial/office/domestic setting was perfectly acceptable in an age when the exact time was unimportant.

The plan

I am not going to tackle this project just yet but fortunately, it has seen servicing. I can identify at least three newer bushings. There does not appear to be significant play in the movement which is always a good sign so, there should not be a problem if the servicing is delayed for a while.

The movement is not particularly dirty so, I oiled the movement, mounted it on the wall, attached the pendulum, and put it in beat.

Taking the movement apart and addressing any wear issues does not concern me but I must learn more about how to set the preload on the mainspring, which has its own winding arbour (not accessible through the dial) before I dive deeper into servicing this movement.

The clock came without a key and I had to order one, a very large #11 key.

In the meantime, the clock is happily ticking away on my office wall.