“My 2824 reads 220° of amplitude — is that bad?” It is probably the most frequently asked question on watch forums, and the one that attracts the most contradictory answers. Before concluding that a service is due, eliminate three causes of false low amplitude in order, and only then look at the real mechanical causes.
Step 1 — Check the lift angle you entered
A timegrapher does not measure amplitude: it derives it from the lift angle you typed into the machine. A 3° error shifts the reading by roughly ten degrees. An NH35 (53°) measured with a default setting of 52° or 50° will display several tens of degrees less than reality — and many forum “faults” end right there. Our lift-angle table gives the manufacturer's value and the expected normal amplitude for common calibres: 50° and 270–310° for an ETA 2824-2, 53° and 230–280° for a Seiko NH35, 51° and 230–290° for a Miyota 9015.
Step 2 — Control the measuring conditions
Amplitude is only meaningful on a fully wound movement, settled for at least 15 to 30 minutes, dial up, with no rotor draining energy during the reading. On an automatic worn since morning, a midday reading means nothing. Also measure 24 hours after full wind: the amplitude drop between 0 h and 24 h says far more about mainspring health than the raw fully-wound figure.
Step 3 — Read the trace, not just the number
The timegrapher trace tells the story the number hides. Two clean parallel lines but low: insufficient energy (mainspring, congealed oil, dirty train). Thick fuzzy lines: dirt or a damaged pivot. Saw-tooth trace: a wheel out of round or a bent tooth. Irregular beat: an escapement or roller problem. A positional delta above 40–50° between flat and vertical points to balance pivots or an end-shake out of tolerance.
Step 4 — The real mechanical causes
Once false positives are eliminated, the statistical order is simple: aged or missing lubricant (by far the first cause, especially on the pallet stones), dirt in the train and jewels, a tired mainspring that slips too early, magnetism (typical symptoms: sudden gain, amplitude collapsing), and finally axial play out of tolerance. Our lubrication-points table states which oil family goes where, and the end-shake table gives the acceptable orders of magnitude per wheel.
When should you worry?
A well-serviced modern watch holds 270–310° dial up depending on the calibre. Below 250° with a correct lift angle, the rate becomes sensitive to position and shocks. Below 220° the escapement risks knocking and galloping: the watch needs a service, not a regulator tweak. Beware, though, of long-reserve calibres (Powermatic 80: 230–270° is normal) too often judged by 2824 standards.
Frequently asked questions
220° on an NH35 — service needed?
Not necessarily: the NH35 normally runs between 230 and 280°, and its lift angle is 53°. First check that the machine is set to 53° and that the watch is fully wound.
Can amplitude be raised by moving the regulator?
No. The regulator affects rate (gain/loss), never amplitude, which depends on available energy and friction.
How much positional amplitude drop is acceptable?
In practice, 40 to 50° maximum between the best flat position and the worst vertical position on a healthy modern wristwatch calibre.
Want to read a trace like a watchmaker? The Décalibre curriculum breaks timegrapher diagnosis down trace by trace in its laboratory unit.