TABLE SHOWING THE PLACE OF THE CENTRES UPON THE SCALE.
+--------------------------------------------------------------+ | CENTRES FOR THE FLANKS OF THE TEETH. | +--------------------------------------------------------------+ | PITCH IN INCHES AND PARTS. | +------+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ |Number| | | | | | | | | | | | | | | | of | | | | | | 1 | 1-| 1-| 1-| 2 | 2-| 2-| 3 | 3-| |teeth.|1/4|3/8|1/2|5/8|3/4| |1/4|1/2|3/4| |1/4|1/2| |1/2| +------+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ | 13| 32| 48| 64| 80| 96|129|160|193|225|257|289|321|386|450| | 14| 17| 26| 35| 43| 52| 69| 87|104|121|139|156|173|208|242| | 15| 12| 18| 25| 31| 37| 49| 62| 74| 86| 99|111|123|148|173| | 16| 10| 15| 20| 25| 30| 40| 50| 59| 69| 79| 89| 99|119|138| | 17| 8| 13| 17| 21| 25| 34| 43| 50| 59| 67| 75| 84|101|117| | 18| 7| 11| 15| 19| 22| 30| 37| 45| 52| 59| 67| 74| 89|104| | 19|...| 10| 13| 17| 20| 27| 35| 40| 47| 54| 60| 67| 80| 94| | 20| 6| 9| 12| 16| 19| 25| 31| 37| 43| 49| 56| 62| 74| 86| | 22| 5| 8| 11| 14| 16| 22| 27| 33| 39| 43| 49| 54| 65| 76| | 24|...| 7| 10| 12| 15| 20| 25| 30| 35| 40| 45| 49| 59| 69| | 26|...|...| 9| 11| 14| 18| 23| 27| 32| 37| 41| 46| 55| 64| | 28| 4| 6|...|...| 13|...| 22| 26| 30| 35| 40| 43| 52| 60| | 30|...|...| 8| 10| 12| 17| 21| 25| 29| 33| 37| 41| 49| 58| | 35|...|...|...| 9| 11| 16| 19| 23| 26| 30| 34| 38| 45| 53| | 40|...| 5| 7|...|...| 15| 18| 21| 25| 28| 32| 35| 42| 49| | 60| 3|...| 6| 8| 9| 13| 15| 19| 22| 25| 28| 31| 37| 43| | 80|...| 4|...| 7|...| 12|...| 17| 20| 23| 26| 29| 35| 41| | 100|...|...|...|...| 8| 11| 14|...|...| 22| 25| 28| 34| 39| | 150|...|...| 5|...|...|...| 13| 16| 19| 21| 24| 27| 32| 38| | Rack.| 2|...|...| 6| 7| 10| 12| 15| 17| 20| 22| 25| 30| 34| +------+---+---+---+---+---+---+---+---+---+---+---+---+---+---+]
The requisite number on the graduated edge for pitches beyond 3-1/2 (the greatest given in the tables), may be obtained by direct proportion from those given in the tables. Thus for 4 inch pitch, by doubling the numbers given for a 2 inch pitch, containing the same number of teeth, for 4-1/2 inch pitch by doubling the numbers given for a 2-1/4 inch pitch. If the pitch be a fraction that cannot be so obtained, no serious error will be induced if the nearest number marked be taken.
