
FRACTIONAL 3 Flute Countersink Series DC • in 603 Vc Fractional Hardness (sfm) 1/8 3/16 1/4 3/8 1/2 3/4 1 125 RPM 3820 2547 1910 1273 955 637 478 ≤ 175 Bhn or Fr 0.0008 0.0012 0.0016 0.0024 0.0031 0.0047 0.0063 ≤ 7 HRc (100-150) Feed (ipm) 3.0 3.0 3.0 3.0 3.0 3.0 3.0 CARBON STEELS1018, 1040, 1080, 1090,10L50, 1140, 1212,12L15, 1525, 1536≤ 300 Bhnor≤ 32 HRc60(48-72)RPMFrFeed (ipm)18340.00071.312220.00111.39170.00141.36110.00211.34580.00281.33060.00431.32290.00571.3 ≤ 425 Bhn 45 RPM 1375 917 688 458 344 229 172 or Fr 0.0004 0.0007 0.0009 0.0013 0.0017 0.0026 0.0035 ≤ 45 HRc (36-54) Feed (ipm) 0.6 0.6 0.6 0.6 0.6 0.6 0.6 P 95 RPM 2903 1935 1452 968 726 484 363 ≤ 275 Bhn or Fr 0.0007 0.0010 0.0014 0.0021 0.0028 0.0041 0.0055 ≤ 28 HRc (76-114) Feed (ipm) 2.0 2.0 2.0 2.0 2.0 2.0 2.0 ALLOY STEELS ≤ 375 Bhn 60 RPM 1834 1222 917 611 458 306 229 4140, 4150, 4320, 5120, or Fr 0.0007 0.0010 0.0013 0.0020 0.0026 0.0039 0.0052 5150, 8630, 86L20, 50100 ≤ 40 HRc (48-72) Feed (ipm) 1.2 1.2 1.2 1.2 1.2 1.2 1.2 35 RPM 1070 713 535 357 267 178 134 ≤ 450 Bhn or Fr 0.0004 0.0006 0.0007 0.0011 0.0015 0.0022 0.0030 ≤ 48 HRc (28-42) Feed (ipm) 0.4 0.4 0.4 0.4 0.4 0.4 0.4 ≤ 250 Bhn 53 RPM 1620 1080 810 540 405 270 202 or Fr 0.0004 0.0006 0.0009 0.0013 0.0017 0.0026 0.0035 STAINLESS STEELS ≤ 24 HRc (42-64) Feed (ipm) 0.7 0.7 0.7 0.7 0.7 0.7 0.7 (FREE MACHINING) 303, 416, 420F, 430F 440F ≤ 330 Bhn 46 RPM 1406 937 703 469 351 234 176 or Fr 0.0004 0.0005 0.0007 0.0011 0.0014 0.0021 0.0028 ≤ 36 HRc (37-55) Feed (ipm) 0.5 0.5 0.5 0.5 0.5 0.5 0.5 M 28 RPM 856 570 428 285 214 143 107 ≤ 275 Bhn STAINLESS STEELS(DIFFICULT) or Fr 0.0005≤ 28 HRc(22-34)Feed (ipm)0.40.00070.40.00090.40.00140.40.00190.40.00280.40.00370.4 304, 316, 321, 13-8 PH, 15-5PH, 17-4 PH, ≤ 375 Bhn 21 RPM 642 428 321 214 160 107 80 Custom 450 or Fr 0.0002 0.0002 0.0003 0.0005 0.0006 0.0009 0.0012 ≤ 40 HRc (17-25) Feed (ipm) 0.1 0.1 0.1 0.1 0.1 0.1 0.1 105 RPM 3209 2139 1604 1070 802 535 401 ≤ 220 Bhn or Fr 0.0009 0.0014 0.0018 0.0027 0.0036 0.0054 0.0072 CAST IRONS ≤ 19 HRc (84-126) Feed (ipm) 2.9 2.9 2.9 2.9 2.9 2.9 2.9 K Gray, Malleable, Ductile 75 RPM 2292 1528 1146 764 573 382 287≤ 330 Bhn or Fr 0.0009 0.0014 0.0018 0.0027 0.0037 0.0055 0.0073 ≤ 36 HRc (60-90) Feed (ipm) 2.1 2.1 2.1 2.1 2.1 2.1 2.1 continued on next page 320 DRILLS www.kDyRoIcLeLrSa-sgstool.com