Anniversary or 400 Day Clocks WS-502

Anniversary or 400 Day Clocks WS-502
Anniversary, or 400 day clocks, are frequently encountered in the repair shop and are often poorly understood by the repair person. We will study these clocks with emphasis on the problems unique to them. Often the fault is as simple as a broken or bent suspension spring. We will learn to replace this spring using the Horolovar 400 Day Clock Repair Guide as a reference. Another major fault is a poorly adjusted escapement; we will learn to diagnose and to properly adjust it to restore the clock to running condition. The safe handling of the mainspring is important and we will demonstrate and use the mainspring winder to remove and replace it. Setting the beat is also of critical importance and often misunderstood; we will learn what constitutes “in beat” and how to accomplish this vital step.

You will need to bring a 400 day clock and a suitable replacement suspension spring with you to class. A Kundo or Schatz standard size model is, by far, the best choice. We have copies of the “Horolovar 400 Day Repair Guide” you may use but you will want your own copy if you are planning on repairing these clocks. A word of caution however; the Tenth Edition is far superior to earlier editions and the only one I would consider buying. Please contact the instructor if you have any questions. There are no tools required other than suitable magnifier such as a 2 to 4 power loupe for observing the escapement.

Upon completing the course the student should be able to:

  • Disassemble and reassemble the 400 day movement
  • Remove and replace the mainspring
  • Adjust the escapement of 400 day clocks
  • Select and install the correct suspension spring
  • Safely remove and replace the mainspring
  • Set the beat
  • Regulate the timekeeping of the 400 day clock

Instructor: Al Dodson

Please contact Education at or (717) 684-8261 ext. 237 with any questions
Workshop Fee:
NAWCC Member

$380 Early Bird (before 02/21/2018)
$440 Regular

Non Member

$420 Early Bird (before 02/21/2018)
$480 Regular

Lab Fee: $20.00 (is included in the price of the workshop).

3/21/2018 - 3/22/2018
NAWCC School of Horology 514 Poplar Street Columbia, PA 17512 UNITED STATES
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