Table 14. Cutting Speeds and Feeds for Milling Ferrous Cast Metals Table 14. (Continued) Cutting Speeds and Feeds for Milling Ferrous Cast Metals
End Milling
Face Milling
Slit Milling
Uncoated Carbide
Coated Carbide
Uncoated Carbide
Coated Carbide
Uncoated Carbide
Coated Carbide
HSS
HSS
Ceramic
CBN
Brinell Hardness Number
f = feed (0.001 in/tooth), s = speed (ft/min) Metric Units: f 3 25.4 = mm/rev, s 3 0.3048 = m/min Opt. Avg. Opt. Avg. Opt. Avg. Opt. Avg. Opt. Avg. Opt. Avg. Opt. Avg. Opt. Avg. Opt. Avg. Cast Steels
Speed (fpm)
Material
(Low carbon): 1010, 1020
100-150 100 f s 125-175 95 175-225 80
7 25
4 70
7 245 †
4 410
7 420
4 650
39 265‡
20 430
39 135 †
20 260
39 245
20 450
(Medium carbon): 1030, 1040 1050 {
225-300 60 150-200 85 200-250 75 250-300 50
f s
4 400
7 345
4 560
39 205‡
20 340
39 65 †
20 180
39 180
20 370
7 20
4 55
7 160 †
(Low-carbon alloy): 1320, 2315, 2320, 4110, 4120, 4320, 8020, 8620
{
175-225 70 f s 225-250 65 250-300 50 f s
4 310
39 45 †
20 135
7 15
4 45
7 120 †
(Medium-carbon alloy): 1330, 1340, 2325, 2330, 4125, 4130, 4140, 4330, 4340, 8030, 80B30, 8040, 8430, 8440, 8630, 8640, 9525, 9530, 9535 {
39 25
20 40
300-350 30 For HSS (high-speed steel) tools in the first speed column only, use Table 15a for recommended feed in inches per tooth and depth of cut. End Milling: Table data for end milling are based on a 3-tooth, 20-degree helix angle tool with a diameter of 1.0 inch, an axial depth of cut of 0.2 inch, and a radial depth of cut of 1 inch (full slot). Use Table 15b to adjust speeds for other feeds and axial depths of cut, and Table 15c to adjust speeds if the radial depth of cut is less than the tool diameter. Speeds are valid for all tool diameters. Face Milling: Table data for face milling are based on a 10-tooth, 8-inch diameter face mill, operating with a 15-degree lead angle, 3 ∕ 64 -inch nose radius, axial depth of cut = 0.1 inch, and radial depth (width) of cut = 6 inches (i.e., width of cut to cutter diameter ratio = 3 ∕ 4 ). These speeds are valid if the cutter axis is above or close to the center line of the workpiece (eccentricity is small). Under these conditions, use Table 15d to adjust speeds for other feeds and axial and radial depths of cut. For larger eccentricity (i.e., when the cutter axis to workpiece center line offset is one half the cutter diameter or more), use the end and side milling adjustment factors (Table 15b and Table 15c) instead of the face milling factors. Slit and Slot Milling: Table data for slit milling are based on an 8-tooth, 10-degree helix angle tool with a cutter width of 0.4 inch, diameter D of 4.0 inches, and a depth of cut of 0.6 inch. Speeds are valid for all tool diameters and widths. See the examples in the text for adjustments to the given speeds for other feeds and depths of cut. Tool life for all tabulated values is approximately 45 minutes; use Table 15e to adjust tool life from 15 to 180 minutes. The combined feed/speed data in this table are based on tool grades (identified in Table 16) as follows: uncoated carbide = 15 except † = 20; end and slit milling coated carbide = 10; face milling coated carbide = 11 except ‡ = 10. ceramic = 6; CBN = 1.
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