These are starting points, not a fixed standard — they vary by tool maker, geometry, coating, flute count and rigidity. Too low a chip load makes the edge rub instead of cut, building heat and dulling the tool; too high overloads the flute and risks breakage. At light radial engagement (small stepover) multiply the listed value by the chip-thinning factor so the actual chip thickness still lands in the cutting range, then dial in by chip colour, sound, finish and tool life. Values are in millimetres per tooth; 1 mm ≈ 0.0394 in (≈39 thou), so 0.050 mm/tooth ≈ 0.002 in.
| Cutter Ø (mm) | Aluminium (mm/tooth) | Steel (mm/tooth) | Stainless (mm/tooth) |
|---|---|---|---|
| 1.5 | 0.010 | 0.005 | 0.004 |
| 3 | 0.025 | 0.013 | 0.010 |
| 6 | 0.050 | 0.025 | 0.020 |
| 8 | 0.064 | 0.038 | 0.030 |
| 10 | 0.075 | 0.050 | 0.040 |
| 12 | 0.090 | 0.064 | 0.050 |
| 16 | 0.110 | 0.080 | 0.064 |
| 20 | 0.130 | 0.100 | 0.080 |
| 25 | 0.150 | 0.115 | 0.090 |
Source: Typical carbide-end-mill starting values — manufacturer data varies; tune by chip colour, sound, finish and tool life. Apply radial chip thinning at light radial engagement.