mined without the necessity even of referring to the table. That is, the number of the taper is the number of tenths of an inch in diameter at the small end, the number of eighths of an inch at the large end, and the number of halves of an inch in length or depth. For example: the No. 6 taper is six eighths () inch diameter at large end, six tenths (1) diameter at the small end and six halves (3 inches) in length. Similarly, the No. 16 taper is 16, or 2 inches diameter at the large end; 18 or 1.6 inches at the small end; 16 or 8 inches in length. THE SELLERS' TAPER THE system of tapers used by William Sellers & Company, Inc., of Philadelphia, Pa., in lathes, drilling and boring machines, is given in the preceding table. The taper is inch per foot and each size of taper is splined as shown for a key the dimensions of which are included in the table. The pitch of the spiral for the drills used by the company is also included. These reamer sizes are so proportioned that each overlaps the size smaller about inch मल 1/ .156" .172" 32 .193" 11/ 64 3 n 16 711 37 .250" 1" .289" 197 64 11/ •341" 32 •409" 32 •492" •591" 74 .706" .857" 83" 1.013" I 234567890 10 II 13 14 15 16 17 18 .0026 .0033 32.0002.0002.0003.0007.0010 .0013 .0016 .0020 1.0003.0005.0007.0013 .0020 .0026 .0033 .0039 .0052 .0065 .0007.0010.0013 .0026 .0039 .0052 .0065 0078 .0104 .0130 1.0010.0015 .0020.0039.0059 .0078 .0098 .0117 .0156 0195 .0013.0020.0026.0052.0078 .0104 0130 .0156 0208 .0260 5.0016.0024.0033.0065.0098 .0130 .0163 .0195 .0260 0326 6 .0020.0029 .0039.0078.0117 .0156 .0195 0234 0312 .0391 .0023.0034.0046.0091.0137 0182 .0228 .0273 0365 0456 .0026.0039.0052.0104.0156 0208 .0260 0312 0.417 0521 6.0029 .0044.0059 .0117.0176 0234 .0293 0352 0469 .0586 .0033.0049.0065.01 30.0195 .0260 .0326 .0391 0521.0651 11.0036.0054.0072.0143.0215 .0286 .0358 .0430 0573 .0716 .0039.0059.0078.0156 .0234 0312 .0391 .0469 .0625 .0781 .0042.0063.0085.0169 .0254 0339 0423 .0508 .0677 .0846 .0046.0068.0091.0182 .0273 0365 .0456 0547 .0729 .0911 1.0049.0073.0098.0195.0293 0391 .0488 .0586 .0781 .0977 .0052.0078.0104.0208.0312 0417 0521 .0625 .0833 .1042 0104.0156.0208.0417.0625 .0833 .1042 .125 .0156.0234.0312.0625.0937 .1250 .1562 .1875 .0208.0312.0417.0833.125 .1667 .2083 .250 .0260.0391.0521.1042.1562 .2083 .2604 .3125 .0312.0469.0625.125.1875 .250 .3125 .375 0365.0547.0729.1458 .2187 .2917 .3646 .0417.0625.0833.1667.250 3333 4167 .500 .0469.0703.0937.1875.2812 .375 4687 5625 .0521.0781.1042.2083.3125 4167 .5208 .625 0573.0859.1146.2292.3437 4583 5729 .6875 .1667 .2083 .250 .3125 3333 4167 4167 .5208 .500 .625 4375 .5833 7292 .6667 .8333 750 .9375 8333 1.0417 9167 1.1458 12 .0625.0937.125 .250 .375 .500 .625 750 1.000 1.250 .0677.1016.1354.2708.4062 5417 .6771 .8125 1.0833 1.3542 .0729.1094.1458 .2917.4375 .5833 7292 .875 1.1667 1.4583 .0781.1172.1562 .3125 .4687 .625 .7812 .9375 1.250 1.5625 .0833.125.1667.3333.500 .6667 8333 1.000 1.3333 1.6667 .0885.1328.1771.3542.5312 .7083 8854 1.0625 1.4167 1.7708 0937.1406.1875 .3750.5625 .750 9375 1.125 1.500 1.875 .0990.1484.1979.3958.5937 .7917 .98961.1875 1.5833 1.9792 .1042.1562.2083.4167.625 .8333 1.0417 1.250 1.6667 2.0833 .1094.1641.2187.4375 .6562 .875 1.0937 1.3125 1.750 2.1875 .1146.1719.2292.4583.6875 .9167 1.1458 1.375 1.8333 2.2917 .1198.1797.2396.4792.7187 9583 1.1970 1.4375 1.9167 2.3958 .125.1875 .250 .500 .750 1.000 1.250 1.500 2.000 2.500 19 20 21 22 23 24 |