Bi-metal hole saws are ideal for cutting perfectly round holes in metals, plastics and wood. A correct drilling speed is important for a good result and a longer lifespan of the holesaw. On this page you´ll find (in two tabels) the correct drilling speeds in revolutions per minute (rpm) for using Bi-Metal HSS holesaws in various materials.
Whenever possible, use cutting oil to lubricate the hole saw when drilling metal. There´s one exception: Cast iron is always drilled dry, so don´t use any sort of lubrication when drilling in this metal.
diam. | RPM | |||
(mm) | plastic | steel | cast iron | inox |
14 | 580 | 580 | 400 | 300 |
16 | 550 | 550 | 365 | 275 |
17 | 500 | 500 | 330 | 250 |
19 | 460 | 460 | 300 | 230 |
20 | 440 | 440 | 290 | 220 |
22 | 390 | 390 | 260 | 195 |
25 | 350 | 350 | 235 | 175 |
27 | 325 | 325 | 215 | 160 |
28 | 315 | 315 | 210 | 155 |
29 | 300 | 300 | 200 | 150 |
30 | 285 | 285 | 190 | 145 |
32 | 275 | 275 | 180 | 140 |
33 | 260 | 260 | 175 | 135 |
35 | 250 | 250 | 165 | 125 |
38 | 230 | 230 | 150 | 115 |
40 | 220 | 220 | 145 | 110 |
43 | 205 | 205 | 135 | 100 |
44 | 1952 | 195 | 130 | 95 |
48 | 180 | 180 | 120 | 90 |
50 | 175 | 175 | 115 | 85 |
54 | 160 | 160 | 105 | 80 |
57 | 150 | 150 | 100 | 75 |
59 | 145 | 145 | 100 | 75 |
60 | 140 | 140 | 98 | 70 |
64 | 135 | 135 | 90 | 65 |
67 | 130 | 130 | 85 | 60 |
68 | 125 | 125 | 80 | 60 |
74 | 120 | 120 | 80 | 60 |
75 | 115 | 115 | 75 | 55 |
79 | 110 | 110 | 70 | 55 |
83 | 105 | 105 | 70 | 50 |
86 | 100 | 100 | 65 | 50 |
89 | 95 | 95 | 65 | 45 |
95 | 90 | 90 | 60 | 45 |
100 | 85 | 85 | 55 | 40 |
114 | 75 | 75 | 50 | 35 |
121 | 75 | 75 | 50 | 35 |
125 | 65 | 65 | 45 | 30 |
133 | 60 | 60 | 40 | 25 |
150 | 55 | 55 | 35 | 25 |
165 | 55 | 55 | 35 | 25 |
178 | 55 | 55 | 35 | 25 |
diam. | RPM | |||
(mm) | copper | aluminium | wood | |
14 | 790 | 900 | 3000 | |
16 | 730 | 825 | 3000 | |
17 | 665 | 750 | 3000 | |
19 | 600 | 690 | 3000 | |
20 | 580 | 660 | 3000 | |
22 | 520 | 585 | 3000 | |
25 | 470 | 525 | 2700 | |
27 | 435 | 480 | 2700 | |
28 | 440 | 470 | 2700 | |
29 | 400 | 450 | 2700 | |
30 | 380 | 425 | 2400 | |
32 | 380 | 425 | 2400 | |
33 | 345 | 390 | 2400 | |
35 | 330 | 375 | 2400 | |
38 | 300 | 345 | 2400 | |
40 | 290 | 330 | 2100 | |
43 | 270 | 305 | 2100 | |
44 | 260 | 295 | 2100 | |
48 | 240 | 270 | 2100 | |
50 | 235 | 260 | 2000 | |
54 | 210 | 240 | 2000 | |
57 | 200 | 225 | 2000 | |
59 | 195 | 225 | 2000 | |
60 | 190 | 220 | 2000 | |
64 | 180 | 205 | 1800 | |
67 | 170 | 195 | 1800 | |
68 | 160 | 185 | 1800 | |
74 | 155 | 175 | 1700 | |
75 | 150 | 170 | 1500 | |
79 | 140 | 165 | 1500 | |
83 | 140 | 155 | 1500 | |
86 | 130 | 150 | 1200 | |
89 | 130 | 145 | 1200 | |
95 | 120 | 135 | 1200 | |
100 | 110 | 130 | 1000 | |
114 | 100 | 105 | 900 | |
121 | 95 | 95 | 900 | |
125 | 90 | 90 | 800 | |
133 | 85 | 85 | 800 | |
150 | 75 | 75 | 800 | |
165 | 75 | 75 | 800 | |
178 | 75 | 75 | 800 |
Some metalworkers insert a sponge soaked in cutting oil into the hole saw. This gives them a self-lubricating hole saw, wich works perfectly.
Remember!
Cast iron is always drilled dry.