Cutting speeds

Suggested cutting speeds (SFM) for drills and taps with high-speed steel (HSS) tools, by material and Brinell hardness.

Cutting speeds
Material Brinell (BHN) Drills S.F.M. Taps—S.F.M. by threads per inch
3-7 1/2 8-15 16-24 25 up
Aluminum 99-101 200-250 50 100 150 200
Aluminum Bronze 170-187 60 12 25 45 60
Bakelite – 80 50 100 150 200
Brass 192-202 200-250 50 100 150 200
Bronze, Common 166-183 200-250 40 80 100 150
Bronze, Phos.; 1/2 Hard 187-202 175-180 25 40 50 80
Bronze, Phos.; Soft 149-163 200-250 40 80 100 150
Celluloid – 100 50 100 150 200
Copper 80-85 70 40 80 100 150
Copper, Mang.; 30% Min. 134 15 – – – –
Duralumin 90-104 200 50 100 150 200
Everdur 179-207 60 20 30 40 50
Iron, Cast; Soft 126 140-150 30 60 90 140
Iron, Cast; Med. Soft 196 80-110 25 40 50 80
Iron, Cast; Hard 293-302 45-50 10 20 30 40
Iron, Cast; Chilled 402 15 5 5 10 10
Iron Malleable 112-126 85-90 20 30 40 50
Monel 149-170 50 8 10 15 20
Nickel, Pure 187-202 75 25 40 50 80
Nickel Steel; 3 1/2% 196-241 60 8 10 15 20
Rubber, Hard – 100 50 100 150 200
Screw Stock; C.R. 170-196 110 20 30 40 50
Steel, Carbon 175-225 70 30 40 50 50
Steel, Drop Forged 170-196 60 12 25 45 60
Steel, Machinery 170-196 110 35 50 60 85
Steel, Magnet; Soft 241-302 35-40 20 40 50 75
Steel, Magnet; Hard 321-512 15 5 10 15 25
Steel, Mang.; 7-13% 187-217 15 15 20 25 30
Steel, Mild; .20-.30C 170-202 110-120 40 55 70 90
Steel, Molybdenum 196-235 55 20 30 35 45
Steel, Spring 402 20 10 10 15 15
Steel, Stainless 150-225 50 8 10 15 20
Steel, Stainless 460-520 20 8 10 15 20
Steel, .40-.50C 170-196 80 20 30 40 50
Steel, Structural; A-36 160 110 40 55 70 90
Steel, Tool; S.A.E. and Forging 149 75 25 35 45 55
Steel, Tool; S.A.E. and Forging 241 50 15 15 25 25
Steel, Tool; S.A.E. and Forging 402 15 8 10 15 20
Zinc, Alloy 112-126 200-250 50 100 150 200