1. All-steel Watches and Semi-steel Watches
Mechanical watches can be divided into all-steel ones and semi-steel ones. What are all-steel and semi-steel? They both refer to the materials of a watch’s outer casing. All-steel watches are those whose outer casings and covers are made of non-rust steel while semi-steel watches are those whose outer casings are copper materials plated with chromium and whose rear covers are non-rust steel. Neither all-steel watches nor semi-steel watches are relevant to the quality of their decks.
2. Drills of a Watch
Most dials are carved with drills (eg. 212ZUAZ) and frequencies (eg. 216 00). The number of a watch’s drills is an important mark of its machinery. In line with its functions, a general mechanical watch demands for 17 to 19 drills while an automatic watch demands for 25 to 30. Actually, too many drills have few functions. They just decorate the watch. However, the higher the frequency, the better the watch. The frequency refers to the times the pendulum sways per hour. A watch with less than 18000 frequencies is called a low frequency one or a slow-sway one while a watch with more than 21600 frequencies is called a high frequency one or a high-sway one. The higher the frequency, the more accurate the time.
3. Varieties of Mechanical Watches
Mechanical watches can be divided into general ones, calendar ones, automatic ones and mechanical-and-automatic calendar ones. They are all added to a suit of calendar casio databank watches for sale or an automatic installation. Some have single calendar forms which only show dates while some other have double calendar forms or complete calendar forms which show weekly calendar or even monthly calendar.
An automatic watch is that whose automatic hammer moves as the arm does, making the automatic installation rolls the spring tight so that time moves. Automatic watches can also be divided into full-automatic ones and semi-automatic ones. The former can be wound no matter what direction it moves in while the latter can be wound only when it moves in one direction. Since the latter have been eliminated and are no longer produced, all new automatic watches are full-automatic ones.
4. According to the structures and functions, mechanical watches can be divided into advanced ones, intermediate ones and elementary ones.
Advanced watches adopt double metal open balance wheels or balance wheels made of alloying materials. There are no less than 16 screws on the balance wheel and more than 17 diamond elements as well as double hairspring whose temperature coefficient is extraordinary low. An advanced watch has the function of “Three Precautions” –Water proof, Shock proof and Magnetization proof. The time error it moves in one night is between positive & negative 30 and 5LS. Normally, this kind of watch has a life span of more than 30 years.
Intermediate watches adopt alloying balance wheels. There are more than 10 screws on the balance wheel and more than 15 diamond elements as well as flat hairspring, with the installations of shock proof and magnetization proof. The time error it moves in one night is between positive &negative 45 and 60 seconds. Normally, this kind of watch has a life span of more than 15 years.
Elementary watches adopt copper alloying balance wheels. There are no screws on the balance wheel but less than 7 diamond elements(some have no diamond). It doesn’t have the function of “Three Precautions”. The time error it moves in one night is positive & negative 80 seconds or so. Normally, this kind of watch has a life span of more than 2 years.