Watch Components Research Articles

Criticality in Bulk Metallic Glass Constituent Elements

Bulk metallic glasses (BMGs), which readily form amorphous phases during solidification, are increasingly being used in first applications of watch components, electronic casings, and sporting goods. The compositions of BMGs typically include four to six elements. Various political and geological factors have recently led to supply disruptions for several metals, including some present in BMG compositions. In this work, we assess the “criticality” of 22 technologically interesting BMG compositions, compare the results with those for three common engineering alloy groups, and derive recommendations for BMG composition choices from a criticality perspective. The criticality of BMGs is found to be generally much higher compared with those for the established engineering alloys. Therefore, criticality concerns should also be considered in the choice between existing and developing novel BMGs.

Roughness checks on watch components

Roughness checking for wristwatch components has some special features. The surfaces are small and complicated in shape, and the roughness is usually monitored with optical instruments capable of making measurements on small areas. It is suggested that the checks are made as follows. At the plant, the checks are made with hand lenses and microscopes by comparing the test surface with that of a standard certified component. In plant laboratories (at checking stations), the roughness should be checked by comparing the profile with that of a standard on a special microscope, which images the profile or the interference fringes~

Contemporary Methods of Watch Production

There is at present no written matter in the English language on watch production, the industry having died out in Britain some thirty years ago. The aim of this paper is to provide the engineer who is not a specialist in the subject with a background knowledge of the methods used in the production of watch components and the special difficulties encountered in watch manufacture. In the first part of the paper the historical development of the watch and the general principles of design are briefly reviewed. A fifteen-jewelled man's wrist-watch with lever escapement is taken as a typical example, in which the features commonly encountered are examined in more detail and the small size of the pinions and pivots is emphasized. The latter part of the paper is devoted to the techniques used in the production of the components (the plates and bridges, turned parts, wheels and pinions, escapement, and balance); their final assembly; and the oiling, springing, and timing, of the finished watch. A general note on the three main categories of watches is amplified by figures illustrating the performance actually attained by a wrist-watch of the highest grade.