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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:  541-559-1090

E-mail address:
MCC's Web site is located at

400-Day Clock Repair Bench Course


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

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
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



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


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

Note: Thanks to Fred Armbrust, John Connolly, John Hubby, 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
Formally Published in Chapter 168's Torsion Times
Formally AWCI's 400-day (Anniversary) clock Bench Course Instructor

The FTP sites can be accessed from Mike's Clock Clinic's Web site.
This site contains all of the FTP (file transfer protocol) sites

mentioned below plus much, much  more.

The FTP sites are as follows:

Atmos Clock FTP site.
Repair Web FTP site.
Main Earthlink FTP site (contains all of the above).

            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


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

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