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# What is a Clock Pendulum Suspension Spring?

*   [Knowledge Base](https://www.clockworks.com)
*   Clock Pendulum Suspension Spring Information

### Article sections

### Clock Pendulum Suspension Spring

Naturally, [suspension springs](https://www.clockworks.com/product/clock-pendulum-suspension-spring-hanger) do not have to be exact in length. If the clock runs slow, simply raise the [pendulum bob](https://www.clockworks.com/product/mechanical-clock-pendulum-bob) with the [rating nut](https://www.clockworks.com/product/clock-pendulum-rating-assembly) at the bottom. Likewise, if the clock is running fast then turn the [rating nut](https://www.clockworks.com/product/clock-pendulum-rating-assembly) to lower the [pendulum bob](https://www.clockworks.com/product/mechanical-clock-pendulum-bob).

### Most common springs

By and large, [suspension spring A](https://www.clockworks.com/product/mechanical-clock-suspension-spring) is the most common style [suspension spring](https://www.clockworks.com/product/clock-pendulum-suspension-spring-hanger). Of course, it is most likely the one by default. If the old [suspension spring](https://www.clockworks.com/product/clock-pendulum-suspension-spring-hanger) looks similar to this one then it is right. As a general rule of thumb, small mantle clocks take [suspension A1](https://www.clockworks.com/product/mechanical-clock-suspension-spring), wall clocks and small grandmother units will take [suspension A2](https://www.clockworks.com/product/mechanical-clock-suspension-spring). The [A3](https://www.clockworks.com/product/mechanical-clock-suspension-spring) size is for grandfather clock units with a larger [pendulum bob](https://www.clockworks.com/product/mechanical-clock-pendulum-bob) diameter. This size can also be seen on Grandmother clocks with larger bob diameters. The larger [A3](https://www.clockworks.com/product/mechanical-clock-suspension-spring) is used with large bob diameters so the bob will not wobble front to back. If using a pendulum with a [bob](https://www.clockworks.com/product/mechanical-clock-pendulum-bob) of 8 1/2 inch diameter or larger please order [Suspension A3](https://www.clockworks.com/product/mechanical-clock-suspension-spring) for this reason.

### Not as common

[Urgos](https://www.clockworks.com/clock-movement/urgos-clock-movement.html) uses the single hook style as seen in picture [suspension B](https://www.clockworks.com/product/urgos-clock-pendulum-suspension). However [suspension A](https://www.clockworks.com/product/mechanical-clock-suspension-spring) was the very most common to use. Very old antique round movements mainly use [Suspension C](https://www.clockworks.com/product/antique-clock-suspension-spring) and [Suspension D](https://www.clockworks.com/product/antique-pendulum-suspension-spring). These are mainly [French](https://en.wikipedia.org/wiki/French) clocks and US made units made prior to 1945.

_The content of this website is copyright by [Clockworks](https://www.facebook.com/ClockworksUSA) and written by [James Stoudenmire](https://www.facebook.com/james.stoudenmire) in year 2020_

Last Updated: 2 months ago in

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