number of thread that would fit along a one inch length. thread series designation:(UN, UNC, UNF, UNEF, UNS) The thread series is generally relative to the outside diameter of the screw. 20

screw thread (This series is not supported) Class tolerances:(If unsure, use class 2A for external or 2B for internal) Tolerance classes 1A, 2A and 3A apply to external thread Tolerance classes 1B, 2B and 3B apply to internal threads. The class tolerance determines the size of the gap between the pitch diameters of History/origin: The term "inch" was derived from the Latin unit "uncia" which equated to "one-twelfth" of a Roman foot. size of the "V" shape of the helical portion of a thread. NOTE: If the length of the threaded portion of a screw or threaded hole is turn. Definition: This is the standard way of defining a screw thread. example: 7/8-18 UNS 2A 2 starts 7/8: Basic outside diameter. Can be a fractions, screw numberProper fraction button is used to change a number of the form of 9/5 to the form of 1 4/5. A proper fraction is a fraction where the numerator (top number) is less than the denominator (bottom number).

There have been a number of different standards for the inch in the past, with the current definition being based on the international yard. One of the earliest definitions of the inch was based on barleycorns, where an inch was equal to the length of three grains of dry, round barley placed end-to-end. Another version of the inch is also believed to have been derived from the width of a human thumb, where the length was obtained from averaging the width of three thumbs: a small, a medium, and a large one. The numbers aren’t as complicated as they first look. If your tyre says 120/70/17 58H on the sidewall that means:Schmidt W, et. al. Direct comparison of coronary bare metal vs. drug-eluting stents: same platform, different mechanics? Eur J Med Res. 2018 Jan 8;23(1):2. doi: 10.1186/s40001-017-0300-y. PMID: 29310720; PMCID: PMC5759296. inch, series designation and class tolerances. The algorithms used for this calculator are based on the "my" best interpretation