Expert: Martin Meyer - 5/13/2008

Question
QUESTION: A suspenion spring came lose when I had to move clock and I can not located it. How can I get a replacement spring. It has emperor movement with a # 451-050H number on it

ANSWER: Hi Bob,

Suspension springs are available from clock materials houses like Timesavers and Merritts Antiques. It is important to get the correct size. Their printed catalogs show the springs in actual sizes; you can place the broken spring on the page over the pictures and see which size is correct. Unfortunately, on their websites the springs do not always show in actual size due to the differences in monitor display sizes, so you should probably get a printed catalog before ordering.


---------- FOLLOW-UP ----------

QUESTION: I do not have the old spring at all, any suggestion on getting the right one?

Answer
Hi again Bob,

There are three general dimensions to be considered in selecting a suspension spring: 1) the strength (thickness) of the spring, 2) the width of the spring, and 3) the length of the spring. The most critical of these is the length. If the spring is too strong, the clock will run slightly faster, and vice versa. If the spring is too wide, it may not fit in the mounting post on the movement. If the spring is too long or too short, the crutch post will not fit centrally in the pendulum leader hole, and will bind against the top or bottom of the hole. (See attached photo).

You have a couple options for selecting the correct spring. First, www.Timesavers.com has four suspension springs for Hermle movements. These are fairly inexpensive, and you could buy all four and see which one fits best. Two of these are larger, two are smaller. Hermle used to use smaller springs, then switched to the larger size on their more recent movements.

Secondly, Black forest imports lists Hermle springs by pendulum length, bridge height and pendulum type (wood stick or Lyre/metal). Your pendulum length is stamped on the back movement plate (85cm, 94cm or 114cm). Your movement is a high bridge (the "H" on the movement number). Their illustration appears to show the smaller size spring, but they don't specify if they have both large and smaller sizes. You can reach the correct page of their catalog at http://www.blackforestimports.com/ItemDetail.asp?varImageName=36&cat=Suspension%