Automatic Watch Running Fast? 6 Causes and How to Fix Each One
Your automatic watch is gaining time, maybe a few seconds a day or several minutes. Before you send it for service, it helps to know what is normal and what is not. In most cases the cause is simple, and in one very common case you can fix it yourself in seconds. An automatic watch's rate depends on its balance wheel and hairspring, the parts most affected by magnetism and shock. Photo: Francis Flinch , CC0, via Wikimedia Commons. In this guide How accurate should it be? How to measure the error Cause 1: Magnetization Cause 2: Resting position Cause 3: Power reserve Causes 4–6: Shock, temperature, service Quick troubleshooting table FAQ First: how accurate should your watch be? Mechanical watches are never as accurate as quartz. Each manufacturer publishes an accuracy tolerance per day: Movement Official tolerance (per day) Seiko NH35 / NH36, 4R35 / 4R36 -20 to +40 seconds Seiko 7S26 -20 to +40 seconds Seiko 6R35 (Prospex, Presage) -15 to +25 seconds Miyota 82...