Back to Mike's Clock Clinic's Main Web Page

Sorry, no longer teaching and I have no alternatives.

I still repair/overhaul the 400-day Anniversary clock


Outline of the 400-day Overhaul Course


Copyright © 1999-2017 Michael P. Murray & Mike's Clock Clinic
Mike's Clock Clinic 1600 Maryland Avenue Myrtle Point, OR 97458-1508 In continuous horological service since 04/01/82 Phone: 310-225-5645, or 877-286-6762 (Toll Free) E-mail address: MCC's Web site is located at
400-Day Clock Repair Bench Course SERVICING AND REPAIR OF 400-DAY CLOCKS A TWO-DAY COURSE COURSE OUTLINE AND STUDENT REQUIREMENTS This two day course is designed for the clock repair person or hobbyist who is already proficient with basic clock service and repair techniques, such as: disassembly and cleaning, mainspring removal and replacement from a spring barrel, pivot straightening and repivoting, barrel and wheel tooth repair and/or replacement, rebushing, reassembly and regulation. The course is specific to 400-Day type torsion pendulum clocks, however the principles herein apply as well to 8-Day, 30-Day, 100-Day, and 1000-Day mechanical torsion pendulum clocks made in the period from the 1870's through the 1980's. Extensive reference will be made to the Horolovar 400-Day Clock Repair Guide, 10th Edition. The following specific topics are covered, with the student performing each task on their own clock: FIRST DAY: Basic disassembly, inspection, cleaning, repair, assembly and regulation Disassembly Mainspring removal and inspection Inspection and cleaning all other parts, repairs as needed (We will NOT cover repivoting, teeth replacement, or wheel and pinion machining) Plate polishing Initial movement assembly and test of train operation through escape wheel Final movement assembly and test of pallet arbor lock and drop Clock assembly including suspension unit and suspension fork adjustment Winding and setting the beat Final assembly and regulation SECOND DAY: Review of First Day, typical problem diagnosis and advanced adjustments Review with questions and answers from First Day Class Clock runs too fast or too slow Clock runs for a period of time and stops Pendulum wobbles and clock running seems weak Pendulum over swing too small, clock stops Escapement "flutters" regardless of suspension fork position Special considerations for the Kaiser Universe Occasional second wheel slippage Missing anchor counter-weights Elgin by S. Haller, Plate # 1522B, the "unrepairable one" Schatz "49" models with 3rd wheel barrels MATERIALS AND TOOLS REQUIRED, TO BE BROUGHT TO CLASS BY STUDENT MATERIALS: 1. At least one 400-Day clock. This clock does not have to be working, but must be complete with all parts including the suspension spring assembly. Any make or model will do, try to be sure all the pivot are not broken or severely bent as repivoting will not be covered. Also, please check that all wheels are whole because teeth replacement and wheel and pinion machining will not be covered. I have a full compliment of suspension springs and a limited supply of top blocks, bottom blocks, and forks parts. I'll also, carry all possible mainsprings. All parts used in class will be sold at cost plus 10% and I'll only sell parts for the particular clock you bring into class. 2. Horolovar 400-Day Clock Repair Guide, 10th Edition 3. Any paste brass polish, such as Dursol, Simichrome or Peck 4. Cleaning and polishing rags (terry cloth, old T-shirts, well used 3M scrubbee pads) 5. Rodico TOOLS: 1. Basic clock service and repair tools: Miniature pliers (gripping type, flat jaw, needle nose, sidecutter); Screwdriver assortment, blade width 1 mm to 6 mm; Large screwdriver or angle screwdriver with 8 mm wide blade; Miniature file set, fine cut; Small brass head hammer Clamps (small C-clamps or parallel clamps) 2. 2 tweezers (any combination of # 3, # 5, # AA, or # MM) 3. 5 sided cutting broach and smooth broaches 4. 6' extension cord and one electric strip with at least a 4 plugs & a bench lamp 5. 4/0000 or 6/0000 emery paper & 4/0000 or 6/0000 steel wool 6. Avery labels or any like product 7. Assembly Clamps (3 or more) 8 Crow's foot 9. High heat source such as a butane or propane torch 10. Pegwood (Hard round toothpicks) & Pithwood 11. Portable bench riser of at least 8" x 12" x 6" high 12. Portable bench vise 13. Small pair of scissors 14. Surgeon-type or cloth gloves 15. Any of your own bench hand tools 16. Any Anniversary specific parts that you may have accumulated 17. Any Anniversary specific tools that you may have accumulated 18. Set of let down keys or a slotted let down handle 19. Mainspring winder (optional but recommended if you have one) 20. Magnifying headset or loupe 21. Precision Micrometer (must read or interpolate to 4 decimal places, either in inches or millimeters) 22. Dial Caliper (should read to 3 significant figures) 23. Pickup Amplifier (a timer such as Timetrax or Microset is optional but desirable if you have one) II Rev. 2 8/99 PAGE 1 through 3 by John Hubby, 077889 Copyright 1999-2013 by John Hubby and Michael P. Murray & Mike's Clock Clinic

Note: Thanks to Fred Armbrust, John Connolly, John Losch, Les McAlister, Mike Murray, and Joe Rabushka who reviewed and contributed to the material in this course.
END of outline						


Michael P. Murray
Memberships Include:

National Association of Watch & Clock Collectors
An Internet private E-mailing list called Clocksmiths
N.A.W.C.C. International 400-day Clock Chapter # 168
Published in Chapter 168's Torsion Times
Formally AWCI's 400-day (Anniversary) clock Bench Course Instructor

            A service from,   E-mail address
            Mike Murray         Founder of Clocksmiths

A specialist in Atmos and 400-day clock repair.
Also, I overhaul most plug in electric clocks.
In continuous service since 04/01/1982.

Mike's Clock Clinic  Memberships: Clocksmiths & NAWCC
My Web site is located at
Main FTP site is located at

This Web page has been accessed


Back to Mike's Clock Clinic's Main Web Page

Copyright © 1999-2017 Michael P. Murray & Mike's Clock Clinic

Back to the top of this page

Created in December of 1999 and last updated January 07, 2017.