TIMEX Model 85 Electric Calendar Watch

Movement Description

The Timex M-85 (Caliber 880/881) is a 13-1/2 ligne electric calendar watch movement. It shares the basic movement with the M-84 but features a sophisticated calendar mechanism on the dial side.

The calendar mechanism is instantaneous, switching the date in seconds. It includes a dot indicator alongside the date numeral to signify A.M./P.M.

A.M./P.M. Indicator: When the date numeral is viewed through the dial window, a dot is displayed either above or below the numeral. A dot below indicates A.M.; a dot above indicates P.M.

Date Setting: The date can be set manually by rotating the hands. For quick date setting, move the hands counterclockwise to approximately 9:00 o'clock and then clockwise to just past 12:00 o'clock.

Warning: Since the watch contains permanent magnets, do not attempt to demagnetize it.

Exploded View and Parts List

The following diagram illustrates the components of the TIMEX Model 85 Movement. A table lists each part with its corresponding number.

An exploded view diagram displays the components of the TIMEX Model 85 movement. Parts are shown separated with dashed lines indicating their assembly points. Key components include the main plate assembly, hour wheel, date cam, date ring, and various levers, springs, and screws.

Disassembly and Mechanism Explanation

Date Ring Mechanism Operation

The date ring's operation is driven by the hour wheel. At 12:00, a lobe on the date cam allows the date indexing lever to engage and advance the date ring. This action is instantaneous due to spring tension.

The click (Part No. 2576) secures the date ring in position, also under spring tension.

Unlike many watches, the Timex Electric's date cam is driven directly by the hour wheel. This results in date advancement occurring at both 12 midnight and 12 noon.

The shape of the teeth on the index lever and date ring means each indexing action advances the ring by only 3/4 of a full space at midnight and 1/4 of a full space at noon. This partial advancement enables the A.M./P.M. indicator function.

A.M./P.M. Indicator Details

12:00 Midnight to 12:00 Noon: The date is displayed with a small dot below the numeral.

12:00 Noon to 12:00 Midnight: At 12 noon, the date ring indexes 1/4 space. The numeral moves to the lower part of the window, and a new dot appears above the numeral, indicating P.M.

Two diagrams illustrate the date window's appearance at different times. The first diagram, labeled '12 MIDNIGHT TO 12 NOON', shows a date numeral (e.g., '8') with a small dot positioned below it. The second diagram, labeled '12 NOON TO 12 MIDNIGHT', shows the same date numeral with a small dot positioned above it.

Disassembly, Cleaning, and Lubrication

Disassembly of Calendar Device

To disassemble the calendar device, remove parts in the following order:

1. Date cam 2552/1
2. Second date holder 2553/2 with screw 52535/2
3. Date click 2576
4. Date indexing spring 2575
5. First date holder 2535/1 with screw 52535/1
6. Date indexing lever 2539/1
7. Date ring 2557/1

Note on Hour Hand: When removing the hour hand, ensure it is placed in precise angular position with the slot in the hour wheel so that date switching occurs at 12 o'clock. If removed, replace it in the same position.

Cleaning and Lubricating

Follow all cleaning and lubricating points indicated for the M-84 model for the M-85 as well.

Additional Lubrication Points for M-85:

• Lubricate the bearing of the date cam 2552/1.
• Lubricate the outer edge of the date cam that bears against the date indexing lever.
• Lubricate the guide pins of the date indexing lever 2539/1.
• Lubricate the bearing and working surfaces of the date click.
• Lubricate the working surface of the date indexing spring No. 2575.