A WORKING MODEL · A PRACTICAL FIELD GUIDE
Get to know
the heartbeat.
Follow the energy. Listen to the beat.
Understand the clock before reaching for a tool.
The center time train is simulated. Outer strike/chime weights are illustrative; their mechanisms are independent and not simulated.
Idealized anchor escapement · drawing is schematic, not a tooth-contact simulation. A 30-tooth wheel advances half a tooth per beat.
Listen for equal spaces.
Measuring…Rate is a pendulum-period estimate, not a promise of measured accuracy. Beat intervals are measured from this running simulation. Simulated time pauses when this tab is hidden.
THE PHYSICS, WITHOUT THE MYSTERY
A weight powers it.
A pendulum times it.
Gravity pulls the driving weight down. Gears transmit its torque to the escape wheel. The anchor alternately locks and releases that wheel, while small impulses replace energy lost by the pendulum. The train counts those releases and moves the hands.
The pendulum mostly sets the rate; the weight mostly keeps it moving. More power is not the right cure for a slow clock. Excess drive can change amplitude, loading, and escapement error.
Small-angle period: T ≈ 2π√(L / g)
Physical pendulum: Leffective = I / (m d)
A seconds pendulum has a full period near 2 s and one beat near 1 s. Its ideal effective length is about 0.994 m at standard gravity. Longer periods make this model lose time.
WHAT THE MODEL DOES & DOESN’T DO
Useful physics.
Honest boundaries.
- Integrates the nonlinear pendulum equation at 240 steps per simulated second, with damping and alternating release events.
- Adds a small energy impulse on each powered release. The time weight falls by a fixed amount per release; the illustrative gearing gives about eight days from a full wind at one beat per second.
- Uses a 1 kg equivalent pendulum, a 4 kg time weight, standard gravity, and an illustrative 20% transfer efficiency. These are not specifications for your clock.
- Models beat offset as a shifted release angle. It does not solve pallet shape, recoil, lock/drop, backlash, worn pivots, suspension elasticity, or gear-tooth contact. Damping is viscous only: at zero beat offset the ideal model can keep a tiny swing that would not unlock a real escapement.
- The rate estimate includes the leading amplitude corrections. Actual clocks also have escapement, temperature, suspension, and other errors.
- Case proportions, tooth shapes, and the visible gear train are explanatory. Some clocks use recoil anchors, others deadbeat escapements or different mechanisms.
AT YOUR ACTUAL WORKBENCH
Start with the symptom.
Identify the maker and movement markings first. Case branding alone may not identify the movement. Photograph the weight labels, suspension, crutch, and movement before changing anything.
It swings for a while, then stops
Listen for evenly spaced tick–tock intervals. Check that the case is stable, the pendulum is hanging correctly, and nothing is rubbing the bob, rod, weights, or case. Confirm the correct weights are fitted in their labeled positions and that the time weight has travel left.
Uneven beat, insufficient delivered power, and friction can look similar. Observe first; this model cannot diagnose worn bushings or incorrect pallet lock.
It runs, but gains or loses time
Record the error over a full day against a reliable reference. On a conventional adjustable pendulum, raising the bob generally speeds the clock; lowering it slows the clock. Make small changes per the maker’s instructions and allow another measurement interval.
The slider demonstrates the direction of change. Do not use its millimeters as an exact nut adjustment: real pendulum geometry and adjustment threads differ.
The tick and tock are uneven
Check the clock’s stable setup and the maker’s beat-setting procedure. Equal beat is about the escapement’s relationship to the resting pendulum, not simply the case looking vertical. Some movements self-adjust; others need a specific crutch adjustment.
Do not bend the crutch, pallets, or suspension spring based on this animation. Identify the mechanism before attempting adjustment.
It keeps time but won’t chime or strike
Many three-weight clocks have separate time, quarter-chime, and hour-strike trains. A working time train does not prove that the other two are powered or correctly set. Check labeled weight placement, silent/night settings, and the maker’s instructions.
Chime sequencing, rack-and-snail striking, and hammer setup are outside this simulator.