Please view these information tabs to help with determining the proper Mechanical Clock Pendulums for your clock.
Sequential steps to obtain a pendulum
- 1. First, know who really made the movement. If the clock was made in Germany post WW2, it will be one of four makers. Hermle, Jauch, Kieninger, or Urgos.
If none of these names are on the movement it is still, most likely made by one of these factories. They made movements for other clock makers who had their own name on the movement because they were buying so many.
Best to use the identification page to narrow down exactly who made the clock movement. Then return to this page to continue the process of pendulum measuring on German Clocks.
- 2. Get the CM numbers, or PL numbers from the back plate of the movement itself. Match these numbers with what we are offering.
- 3. Determine the bob diameter. Measure how wide the inside of the case is and then subtract 4 inches. This will be the maximum pendulum bob diameter that the clock case can handle.
- 4. Decide between Lyre, Wood stick, or a brass rod pendulum if the options are there. They all come with a brass round bob for the end, but leading down to the bob can be any of these three styles.
- 5. Order it
- 6. Once received, the pendulum install it on the clock, then Put The Clock In Beat.
Pendulum Measuring on German Clocks
Measure the pendulum on a German Clock from the very top of the movement down to the very bottom of the pendulum rating nut threads.
Naturally, if the clock says something like 94cm, choose 94cm from the list, making sure it also lists the correct bob diameter. Clockworks will calculate the length, making sure it is correct, before shipping it.
A customer may receive the pendulum and think that it is not the correct length. Most likely, this is not the situation. Ordering a pendulum for a Hermle 94cm movement, does not mean a 94cm long pendulum will arrive. The pendulum may be shorter, although it will be correct.
Determine Bob Diameter after Pendulum Measuring on German Clocks
Of course, bob diameters vary so that they will not hit the sides of the case. bob width is determined by the inside of the case width.
Measure how wide the inside of the clock case is and then subtract 4 inches from that measurement. That measurement is the largest diameter Bob that can be used in the clock case. Likewise, a smaller diameter bob can be used, but not a larger one.
Pendulum clocks need to be put "In Beat"
Finally, after installing the new clock pendulum the clock will need an adjustment for it to run correctly. This is very easy to do and only takes a few minutes. Moreover, no mechanical pendulum clock will run right without "Putting The Clock In Beat" first.
Types of Clock Pendulums
There are three basic categories for types of clock pendulums. These are lyres, wood sticks and brass rods. Mantle clocks have very short pendulums which use a mantle bob. This section will not discuss these types of pendulums. Instead, search the keywords mantle bob if working with a mantle clock.
This will bring up the correct product for mantle clocks. What is in this section is the types of clock pendulums available for shelf, wall and floor clocks. Each of them have their own pros and cons. We can make recommendations on what was typical for a particular clock. Ultimately, it comes down to personal preference.
- Brass rod style pendulum for small shelf or wall clocks.
- Metal Lyre style pendulums for floor clocks.
- Wood stick pendulums are for almost everything.
A Metal Lyre pendulum is a type of clock pendulum that is most decorative of pendulums. A floor clock can mean a grandfather, grandmother, or granddaughter clock. Basically, any clock that sits on the floor versus a wall or mantle. These types of clock pendulums are for post WW2 German movements.
This would be Urgos, Kieninger, Jauch and Hermle units.
These are the only post WW2 German units made. Generally speaking, the stamp may have another name on the backplate of the movement. This is due to companies paying a premium to have their name put on the movement. However, this does not change who the actual manufacturer is. In short, the ones who made the movement are one of the German companies already on the above list.
The wood stick type of clock pendulum is sent with no stain on it. This is so the stick can have the same stain to match the clock case. Likewise, a black stick looks nice with the gold bob as well. Certainly, by leaving it plain the customer can customize the stick to whatever color they deem fit.
A wood stick type of clock pendulum consists of the stick, the top hook, the rating assembly and the round bob. They are capable of accepting any size bob and can easily be cut if too long. Because of these qualities, they are the most versatile pendulums out of the three.
Shelf clocks or wall clocks mainly use brass rod types of clock pendulums. It is not common for them to be on granddaughter or grandmother clocks. It is possible but not likely. These pendulums tend to cost more for a couple of reasons.
First, they are made of brass. Of course this is a much more expensive medium than the wood. Second, they are custom cut to size by us here at Clockworks. We will cut it to the exact length needed for the specific clock movement upon ordering. Getting the correct CM length is very important to ensure the brass rod is the right length.
Types of Clock Pendulums In Summary
As shown above, the three styles of pendulums have their own good points and drawbacks. For the most part, wood stick types of clock pendulums tend to be the most versatile. They can have stain, or paint, in any color. Moreover, modifications are fairly easy.
After that, the brass rod would be the next flexible type. They are custom cut to the correct length prior to being sent. Lastly, the lyre pendulum is the most decorative out of the three styles. Modifications to these pendulums are minimal.
Please feel free to contact us if there are any questions on any of these types of clock pendulums. As always, we are here to help. When contacting us, make sure to have the movement number that is on the backplate of the movement itself. This is the only way to know who made the movement. Without this information it is not possible to direct you to which pendulums would be correct. As always, pictures of the movement are always helpful.
Grandfather Clock Pendulum Information
Grandfather clock pendulum information begins with the obvious discussion of length. The length of the pendulum on German units comes in a few CM options.
German units measure the pendulum from the top of the movement to the bottom of the nut threads.
The pendulum itself, the leader it hangs on, and the suspension spring that the leader hangs on.
All three components in centimeters make up that CM length in the drop down menu.
Pendulum length information
To know how long the actual pendulum is, subtract 15CM from the options with the pendulum length.
This will exclude the leader and suspension spring, and be the actual pendulum length from tip to tip off of the clock.
This length can vary as if a larger pendulum bob is selected, the actual length of the pendulum gets longer.
Why the CM length matters at all is because if the pendulum length is not near the CM length of the movement, the clock will not keep time.
So the gearing in the movement and the pendulum length works together to keep time around the specified CM length.
The bob width Options
A Lyre grandfather clock pendulum comes with either a 6 1/2, 8 1/2, or 10 1/2 inch bob diameters. The 'Bob' is the round disk at the bottom of the pendulum.
Moreover, the CM length on the movement will indicate the length of the pendulum from the TOP of the movement all the way down to the bottom of the pendulum nut threads.
This is an approximate length that depends on other factors such as bob diameter and weight of the pendulum.
Basically if the CM is 94CM the pendulum itself will be about 35 inches tip to tip off of the clock, and the 114CM option would put this same measurement at approximately 44 inches.
The Mechanical Clock Pendulum Assembly
The mechanical clock pendulum assembly does not mean just the pendulum alone.
The use of the word assembly means the pendulum consists of three components and not just the pendulum. A pendulum assembly consists of the suspension spring at the top, the leader that hangs on it, and then the pendulum.
Usually mechanical clock pendulum makers are not movement makers and the two are married together by a person or place. A place such as Clockworks or Howard Miller instead of the movement manufacturer. This is interesting because it explains why there can be so many variations in pendulums for one movement.
The pendulum could be a brass rod, wood stick, or metal lyre style.
Pendulum bob diameter size
To determine the bob diameter for a mechanical clock pendulum, need to consider what looks good as well as which one won't whack the sides of the case. A good rule for the bob diameter is it needs two inches on each side to swing.
So if the clock case is 12 inches wide the bob cannot be more than 10 inches. In this example we would need a 10 inch bob but these are not made.
So the choice is clear that for a 12 inch wide clock case the maximum bob size to get is 8 1/2 inches wide. If this rule did not exist and the 10 inch wide bob is run the clock may go tick, knock, tock, knock, as it hits the sides eve