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Duration of Grandfather Clocks

Antique grandfather clocks tend to be weight driven and go for a specific amount of time on a wind. I will cover the standard examples in this blog. For examples of different types of grandfather clocks please visit our grandfather clock stock page by clicking this link:  Antique Clocks For Sale.

1 Day to 1 Year Duration

The most basic of antique grandfather clocks is the simple 30 hour duration antique grandfather clock. These were made generally for simple cottages in the country. They have simple mechanisms with one weight that drives both the striking mechanism and the going side mechanism of the clock. Since the weight drives both sides of the clock is has more work to do and thus it winds out far quicker. The weight is normally about 8lbs in weight driving this clock.

Lovely 30 hour grandfather clock in oak case
30 Hour Grandfather Clock – Bowfield

Bowfield of Melton Antique Grandfather Clock.

Most common is the 8 day clock

The most standard of all antique grandfather clocks is the ‘8-day’ grandfather clock. These clocks have a movement split into two separate sides. One weight driving each side. There is a striking side weight and a going side weight. Each weight has its own separate job to do. The movements tend to be 4 wheel train and the weight of the weight is usually around 13lb each. Sometimes higher quality movements run on a slightly smaller weight, as there is less friction involved. An example of a standard ‘8-day’ grandfather clock is found below.

Lovely London mahogany '8-day' grandfather clock
Henry Jenkins Grandfather Clock C1770

Henry Jenkins Grandfather Clock C1770

Long duration clocks

We are now moving into the realms of the rarer clocks. Every so often you come across a month duration or maybe a 3 or 6 month duration grandfather clock. Months duration grandfather clocks have like the ‘8-day’ grandfather clocks two trains for the mechanism. Usually one weight for the striking side and one for the going side. The movements tend to be 5 wheel trains and tend to wind anti-clockwise. The driving force tends to increase dramatically as well. The weights tend to be around 30lbs in weight each one. That is over the double the weight of an ‘8-day’ example. A lovely month clock can be found below.

Cabinet gets thicker construction on long duration clocks

One important point to note is as the duration of the clock increases the structure of the case gets more robust. This is required to cope with this extra weight. The sides of the case get thicker and construction gets all round slightly better to cope. A month case should be heavier than the equivalent ‘8-day’ example.

Long duration marquetry clock C1690
Lovely Month Duration Marquetry Grandfather Clock

Year Duration Clocks

Finally on very rare occasions you will find year duration antique grandfather clocks. We have only ever owned a handful of these very rare clocks. Some examples use the power from two weights to drive the clock. Alot of power is required to keep the clock running. You can also find some examples that will strike. These are generally on the earlier examples. The later Georgian examples tend to more about timekeeping and precision movements. Weights are very heavy in these clocks. Generally they need steel cable to support the weights. Each weight can be over 60lb. A minimum of 6 wheel train and high pinion counts are found of these types of grandfather clock. Clearly only the top makers produced such clocks.

Daniel Clements

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