Size (clock)
A size is a measure of length used in America and England , which was common in watch technology for the caliber (movement diameter). One size corresponds to 0.8466 mm. The "American movement size" and the English "Lancashire gauge size" are dimensionally identical.
definition
The length measure "Size" is derived directly from the " English inch ".
- 1 engl. Inch = 25.40 mm
- 1 size = 1/30 engl. Inch = 0.8466 mm
The beginning of the scale (shown in red in the table) was arbitrarily set by the American watchmaker Aaron Lufkin Dennison . He took a caliber of 1 + 5/30 engl. Inches, which is 29.63 mm. He defined this size as "0 size". He designated the sizes above "0 Size" as 1, 2, 3, ..., those below "0 Size" as 2/0, 3/0, 4/0 etc. The first smaller gradation was not "1/0 Size" , but called "2/0 Size" (shown in yellow in the table). All gradations were staggered with a distance of 1 size (1/30 inch).
Table for works ≥ "0 Size"
| Size | 0 | 1 | 2 | 3 | 4th | 5 | 6th | 7th | 8th | 9 | 10 | 11 | 12 | 13 | 14th | 15th | 16 |
| mm | 29.63 | 30.48 | 31.33 | 32.17 | 33.02 | 33.87 | 34.71 | 35.56 | 36.41 | 37.25 | 38.10 | 38.95 | 39.79 | 40.64 | 41.49 | 42.33 | 43.18 |
| Size | 17th | 18th | 19th | 20th | 21st | 22nd | 23 | 24 | 25th | 26th | 27 | 28 | 29 | 30th | 31 | 32 | 33 |
| mm | 44.03 | 44.87 | 45.72 | 46.57 | 47.41 | 48.26 | 49.11 | 49.95 | 50.80 | 51.65 | 52.49 | 53.34 | 54.19 | 55.03 | 55.88 | 56.73 | 57.57 |
Table for works ≤ "0 Size"
| Size | 15/0 | 14/0 | 13/0 | 12/0 | 11/0 | 10/0 | 9/0 | 8/0 | 7/0 | 6/0 | 5/0 | 4/0 | 3/0 | 2/0 | 0 |
| mm | 17.78 | 18.63 | 19.47 | 20.32 | 21.17 | 22.01 | 22.86 | 23.71 | 24.55 | 25.40 | 26.25 | 27.09 | 27.94 | 28.79 | 29.63 |
| Size | 30/0 | 29/0 | 28/0 | 27/0 | 26/0 | 25/0 | 24/0 | 23/0 | 22/0 | 21/0 | 20/0 | 19/0 | 18/0 | 17/0 | 16/0 |
| mm | 5.08 | 5.93 | 6.77 | 7.62 | 8.47 | 9.31 | 10.16 | 11.01 | 11.85 | 12.70 | 13.55 | 14.39 | 15.24 | 16.09 | 16.93 |
application
In the 19th and 20th centuries, American watch manufacturers traditionally did not deliver complete watches to the trade, only the movements. This enabled the dealer to put together a watch with a movement and case for the customer as required. For this reason, American type specifications always contain the size (caliber) expressed in "size".
See also
literature
- Steffen Röhner: military pocket watches; (Non-metric dimensions in watchmaking) ; Callwey Munich 1992; ISBN 3-7667-1048-6
Web links
- Volker Vyskocil: Watch technology size
- Carignan Watch Company: Watch movement sizes (English)
- TimeZone: Watch Movement Measuring Systems (English)
- Elgin: Watch Sizes ( Memento from November 29, 2010 in the Internet Archive )
Individual evidence
- ↑ Fritz von Osterhausen: Callweys lexicon ; Munich 1999; ISBN 3-7667-1353-1 ; P. 307.
- ^ German watchmaker's calendar 1926, page 133