Chip load is the thickness each flute removes per revolution. Rearrange the feed rate formula to check whether your program is cutting a real chip or just rubbing.
Chip load = Feed (IPM) / (RPM × flutes)
What the variables mean
| Symbol | Meaning |
|---|---|
| Chip load | Feed per tooth (inches) |
| IPM | Feed rate (inches per minute) |
| RPM | Spindle speed |
| Flutes | Number of cutting edges |
Worked example
30 IPM at 2,292 RPM with 4 flutes: chip load = 30 / (2292 × 4) = 0.0033 in per tooth.
FAQ
Is chip load the same as feed rate? No. Chip load is feed per individual tooth per revolution, while feed rate is the overall table speed in distance per minute, which is derived from chip load, RPM, and flute count combined.
What happens if chip load is too low? Too low a chip load causes the tool to rub rather than cut cleanly, generating excess heat and accelerating wear, similar in effect to running dull tooling, since chip load has both a practical minimum and maximum for a given tool.
Skip the arithmetic with the Chip Load Calculator in Feeds & Speeds.