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Hermle Clock Pendulum Measuring
If a Hermle clock doesn’t keep proper time, the pendulum may be incorrect. To determine if this is the problem, measure all of the components of the pendulum.
Hermle clock pendulum measuring is extremely important. Often enough the CM length stamped on the movement is not the actual pendulum length. Certainly, the CM stamp provides valuable information, however it does not state what the Hermle clock pendulum needs to be from tip to tip. This section describes what the CM stamp represents, as well as how it needs to be measured.
What the CM Represents
To measure a Hermle clock pendulum, start at the very top of the movement. Continue all the way down to the bottom of the rating nut on the pendulum. The CM number will only be accurate to the pendulum length if the bob diameter is small.
In other words, the larger, or the heavier, the bob is, the longer the pendulum needs to be despite the stamped length on the movement. If confused, please email Clockworks in order to determine the best pendulum length. Please provide the Hermle clock pendulum CM length stamped on the back plate of the movement.
Also, include the width of the pendulum bob. The bob is the round disk at the bottom of the pendulum.
Hermle Clock Pendulum Measuring – Parts That are Measured
The Hermle clock pendulum length (**cm) is the distance from the suspension post all the way down. Meaning to the bottom of the pendulum nut threads. This measurement includes the pendulum from tip to tip, the leader it hangs on, and the suspension spring.
This pendulum length will not always be the same as what is marked on the movement. Subsequently there are also other factors that play into this measurement. For instance, the pendulum bob diameter. The larger the pendulum bob diameter, the longer the pendulum length needs to be despite the CM length.
Conclusion
In conclusion, if the Hermle clock pendulum CM length on the old unit matches the CM length on the new unit it will keep proper time with the same pendulum. There are times when the old leader needs to be used on the new movement, but this is not common.
Hi James,
Thanks for your reply. So in short I should order a pendulum using the 33.5CM as the guide. This would get me the 8 inch pendulum??
Yes is true
James Stoudenmire
40yr Clockmaker
Author of Clockworks.com
The movement was bought new in February of 2022 through Clockworks. It has run fast from the start. The CM number is 33.5. The pendulum length is 6 and 5/8th inches or 16.8275 cm.
Pendulum should be 8 inches long for that one.
James Stoudenmire
40yr Clockmaker
Author of Clockworks.com
Hello, I have a 341-021 movement and it runs too fast. I have adjusted the pendulum bob as low as it will go and no change to how fast it runs. Are there any other adjustments?
Is this a new movement? Did it ever keep time with that pendulum if so? What is the CM number on the movement, what is the length of the pendulum from tip to tip when off the clock
James Stoudenmire
40yr Clockmaker
Author of Clockworks.com
Good day, I have a Hermle 341-021 movement that I am looking to replace but have questions on the correct size movement. The movement that is in the clock has had the length marked over so I’m not exactly sure what it’s supposed to be. This is a wall clock with a 3 inch diameter Bob. The length from the top of the movement to the very bottom of the pendulum is 13.25 inches. I have read that you should measure to the middle of the Bob and also read to measure to the bottom of the pendulum. What is the correct way to measure please?
Best to get the in stock 45cm from this link
https://www.clockworks.com/product/new-341-021-clock-movement-by-hermle
And time it, if too slow take an inch off the pendulum length
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I’m sorry but now I’m really confused. If measuring from the top of the movement to the bottom of the pendulum is 13.25 inches, wouldn’t you want a 33.5cm movement? Please help me understand where 45cm comes from.
Oh I see, yes I misread and thought you said the pendulum itself was 13.5 inch. Yes you need the 33.5cm
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I have a Hermle 1051-030 43CM, what is the actual length of the pendulum and diameter of Bob? I don’t see it listed. Thank you.
Pendulum will end up being about 10 1/2 inches tip to tip when off the clock. Bob diameter is whatever you chose that will not wack the sides of the case.
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I’m looking to purchase an old clock that has a A206-012 movement which I intend to replace with a new 131-030 movement. The problem I have is that the clock is missing the pendulum, can you advise me if a replacement is available ? Thanks, Bill
Please order a pendulum for a Hermle 21cm movement in brass rod style
https://www.clockworks.com/product/hermle-brass-rod-clock-pendulum
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Hi. I have a Howard Miller model 610-326 that needs a pendulum. The stamping on the back of the movement says 114 cm, but I’m not sure what size bob it needs. How would I find this information?
Please order either a wood stick pendulum, or a metal lyre pendulum from the below links. The bob diameter is to be 4inches less than the interior width of the clock case, or less. This way it has some room to swing.
Please order a pendulum for a Hermle 114cm movement by clicking one of the below links
For a wood stick style pendulum, here is the link
https://www.clockworks.com/product/wood-stick-pendulum-for-hermle-clocks
Lyre pendulums are at this link
https://www.clockworks.com/product/hermle-lyre-pendulum
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
i have a 1051-0202 11cm / 200-78 movement the clock is wound up tight but the clock forum tells me you can’t wind them so tight as to keep them from running. i put the pendulum on it and give it a push and it will let the escapement move maybe 3 or so teeth and then the escapement stops and the pendulum just runs out of gas. it doe this with the pendulum on or off i can send video of it running it looks clean
Please see this article on how to put a clock in beat
https://www.clockworks.com/posts/mechanical-clock-movement-beat-setting
This may solve it
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Hello, I am want to fit a new Hermle 141.041 into a old mantel clock, unfortunately they have stopped producing 11/12/15 cm pendulum models, the shortest they do is a 21cm however this will not fit in the case, am I able fit a movement 21cm version with a different pendulum? another note the manual silence lever can they be removed or replaced with a shorter one ? thanks
Yes to the silence lever removable or swappable.
We can regear a unit to whatever you like, however there is a $100 added fee for this.
What CM number do you need?
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
If the measurement is taken from the top of the pendulum the L9603 is 105mm to hook, including this I believe the 12cm would be the one, does the 12cm pendulum calculated to include the 105mm leader?
Not understanding, please clarify
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I am trying to find a correct pendulum for a clock that I bought. It didn’t have one. Every one that I’ve tried the clocks runs too fast. Please help
I’m replacing a Hermle 241-080 94cm. The old pendulum leader is 1″ longer than the replacement movement’s. The old leader is not configured so as to fit over the L-shaped movement arm. The new leader is not flat, its oddly shaped and much be fed through a narrow slot and then hung from upper post. Will shorter pendulum cause new movement to run too fast? If so, what can be done.
Hope this reaches someone. Thanks.
Hi
They did change the leader style at one point yes. The leader lengths may not match but the clock will still keep time like it ever did. This is because along with changing the length of the leader there is a gear inside of the movement that was changed also.