Why do mechanical watches have deviations?

　　Generally speaking,Mechanical watchwhy timekeeping is not as accurate as quartz watches.

　　When many consumers purchase products, they usually have this question. Below, we combineQuartz watchesand mechanical watch-related technical characteristics to analyse and interpret.

　　Technical characteristics lead to differences

　　According to the corresponding technical requirements for analogue quartz watches, the instantaneous daily rate for premium products ranges from -0.5 seconds/day to 0.5 seconds/day, whereas mechanical watches are specified as -20 seconds/day to 40 seconds/day (including a total of 4 testing positions: dial-up, 3-hour-up, 6-hour-up, and 9-hour-up). From the perspective of technical requirements, products of the same grade have significant differences in timekeeping requirements. This is mainly because the principles of quartz watches and mechanical watches differ, and the time bases affecting the accuracy of the products are distinct. The time signal module of a quartz watch is composed of electronic components, with the time base being a "quartz crystal oscillator" (or "crystal" for short), which can provide a very accurate time frequency signal to ensure the precision of the watch's timing function. Under normal circumstances, a premium quartz watch can basically achieve zero deviation, and even when calculated based on the maximum value of 0.5 seconds/day, the monthly deviation can still be controlled within 15 seconds. In contrast, mechanical watches are entirely composed of mechanical components, and their time base is the "balance wheel-spring assembly", with the timekeeping error generated being the vibration period error of its balance wheel and hairspring system. Therefore, ensuring the accuracy of the entire system involves a series of issues in the production of mechanical watches, ranging from product design, component processing, component materials, and product assembly, to even the length of the hairspring, all of which affect the timekeeping of mechanical watches in various aspects. Consequently, differences in technical characteristics lead to certain discrepancies in timekeeping performance.

　　Accuracy is relative

　　Meanwhile, many manufacturing enterprises, taking into account the special nature of mechanical watches when products leave the factory, usually adjust mechanical watches to run slightly fast on the premise of meeting internal indicators. The benefit of doing this is that during daily wear, consumers will offset some of the situations where timekeeping runs slightly slow due to various reasons such as insufficient mainspring power, wear of mechanical watch parts, or sludge generated by lubricating oil mixed with impurities. Therefore, when your mechanical watch runs slightly fast, as long as it is within a certain margin of error, it is completely normal. This is a conceptual misconception during the consumption process, because well-known foreign brand mechanical watches currently priced at tens of thousands of pounds or more have test metrics tested through one of the world's strictest tests—"COSC Swiss Chronometer Certification"—ranging from -6 seconds/day to 4 seconds/day. Compared against this index requirement, it is actually inferior to the "pass" grade requirement in the quartz watch standards (GB/T6044-2005 In the "Analogue Quartz Watches" standard, the pass grade index is -1.5 seconds/day to 1.5 seconds/day). Therefore, the accuracy of mechanical watches is relative; if one demands absolute accuracy in a watch, a quartz watch or atomic clock is far superior to a mechanical watch, but doing so would simultaneously strip away the immense charm of mechanical watches.

　　As the old saying goes: error is the soul of a mechanical watch; too small lacks character, too large lacks standard.

　　Finally, mechanical watches value stability rather than simple error, because adjusting error is very straightforward. However, if a mechanical watch has poor stability, there is not much that can be done. Stability refers to the consistency of a mechanical watch's performance, which is the magnitude of the difference in error ranges under various environments.   Stability is influenced by the craftsmanship and materials of the mechanical watch. Therefore, stability is the key factor.

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