Tapping Speed Guide

MATERIALS SPEED FEET PER MINUTE
Aluminum Alloys 90-100
Brass 60-100
Bronze 40-60
Copper 40-60
High Temperature Alloys Cobalt Base 5-10
Iron Base 10-15
Nickel Base 5-10
Iron Ductile Annealed 60
As Cast 30
Tempered 15-20
Gray Annealed 80
As Cast 35-60
Malleable 60
Heat Treated 25-50
Magnesium Alloys Annealed 175
Manganese 20
Molybdenum Alloys Stress Relieved 50
Monel Annealed 20
Nickel Alloys Annealed 25
Plastics Reinforced 25
Thermoplastics 50
Thermosetting Plastics 50
Steels Alloys, Annealed or Cold Drawn 40-60
Quenched & Tempered 15-35
Armor Plate 10
Carbon Steel, Plain Annealed 40-80
Tempered 15-40
Cast, Carbon Annealed 40-50
Tempered 30
Cast, Corrosion Resistant Annealed 20-30
Heat Resistant, as Cast 20-25
Low Alloy Annealed 30-45
Tempered 15-25
Precipitation Hardening, Treated 10-15
Stainless Annealed 15-45
Tempered 15-25
Free Machining, Annealed 45-75
Tool Steels High Speed Annealed 15-25
Water Hardening Annealed 50
Ultra High Strength Steels Annealed 35
Normalized 20
Tempered 3-7
Maraging Steels Annealed 20-15
Maraged 5-10
Tantalum Alloys Stress Relieved 3
Titanium Alloys, Commercial Pure, Annealed 40-60
Alpha & Alpha Beta Alloys Annealed 10-25
Tungsten Alloys Pressed & Sintered 50
Zinc Alloys Die Cast 150

Surface Feet Per Minute to Revolutions Per Minute Conversions

SPEED FEET PER MINUTE 20 25 30 40 50 60 70 80 90 100 110 120 130 140 150
TAP SIZE REVOLUTIONS PER MINUTE
0 1273 1592 1910 2546 3183 3820 4456 5093 5730 6366 7003 7639 8276 8913 9549
1 1047 1308 1570 2093 2617 3140 3663 4186 4710 5233 5756 6279 6808 7326 7849
2 888 1110 1333 1777 2221 2665 3109 3554 3999 4442 4886 5330 5774 6218 6662
3 772 964 1157 1543 1929 2315 2701 3086 3472 3858 4244 4629 5015 5401 5787
4 682 853 1023 1364 1705 2046 2387 2728 3069 3411 3751 4092 4434 4775 5116
5 611 764 917 1222 1528 1833 2139 2445 2750 3056 3361 3667 3973 4278 4584
6 553 691 829 1106 1382 1658 1934 2211 2487 2764 3040 3316 3592 3869 4145
8 466 583 699 932 1165 1398 1631 1864 2097 2330 2563 2796 3029 3262 3495
10 401 502 603 804 1005 1205 1406 1607 1808 2009 2210 2411 2612 2813 3014
12 354 442 531 707 884 1061 1238 1415 1592 1769 1945 2122 2300 2476 2653
1/4 306 382 458 611 764 917 1070 1222 1375 1528 1681 1833 1986 2139 2292
5/16 245 306 367 489 611 733 856 978 1100 1222 1345 1467 1589 1711 1833
3/8 204 255 306 407 509 611 713 815 917 1019 1120 1222 1324 1426 1528
7/16 175 219 262 349 437 524 611 698 786 873 960 1048 1135 1222 1310
1/2 153 191 229 306 382 458 535 611 688 764 840 917 993 1070 1146
9/16 137 172 206 275 344 412 481 550 619 687 756 825 893 963 1031
5/8 122 153 183 244 306 367 428 489 550 611 672 733 794 856 917
3/4 102 128 153 203 255 306 357 407 458 509 560 611 662 713 764
7/8 87 109 131 175 218 262 306 350 392 437 480 524 568 611 655
1 76 96 115 153 191 230 268 306 344 382 420 458 497 535 573