How to get the right mechanical clock key

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Mechanical clock keys

Mechanical clock keys is the clock part that is most frequently lost. Once the clock key is no longer with the clock it always seems to end up missing. With the below information you can order a new key utilizing the clock key size chart.

Getting the right one

We have mechanical clock keys in all the sizes available. Between the key chart or by movement type information below, the chances are good of getting the perfect key. The movement type includes if the clock is made in Germany or USA and when it was made.

This is the fastest and most easiest way to get the clock key. The further back in time we go with clocks the more the key chart would need to be used instead. There will be a stamp with the country of origin on the back plate of the movement and this can help us get the key.

Keys for German units post WW2

German made post WW2 movements that are square or rectangle will take a number 8 keys or crank.

If the clock movement is round and made in Germany the key size is number 4. Some round ones will take a number 3 but if getting a 4 it will still fit and wind the clock either way.

Keys for USA units 1900 - 1950

American clocks made from around 1875 until after the second war almost always take the size 7 clock key. The number 7 keys fits the 8 day time / strike units pretty much every time and this is what USA made the most of. This rule may not apply to Westminster (3 places to wind) or time only (one place to wind) clock movements.

Keys for Korean and Chinese clocks

Size 7 for these units usually. All the 31 day clocks with Asian movements and also US replicas made in India, all take size 7.

The over wound myth

Of course any clock that is not working will be wound all the way up from trying to make it run. Everyone winds it up and the clock does not work so the non working clock is always wound up.

The only way a clock can be over wound is if its been wound up for so long that the mainspring stuck.

When the mainspring is stuck together to itself with rust and goo for so long it may stick that way. This is rarely the situation and usually the clock would have rust on it if the mainspring is so wound up it will not wind down.

The content of this website is copyright by Clockworks and written by James Stoudenmire in year 2022

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