CNC Machining worked example

Chip Load with feed rate of 48 in / min: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop feed rate to 48 in / min, then walk the calculation through step by step. Estimate chip load per tooth from programmed feed rate, spindle speed, and the flute divisor used for the effective tooth count.

The inputs for this scenario

  • Feed rate: 48 in / min (the input this scenario stresses; the baseline uses 96)
  • Spindle speed: 8,000 RPM (held at the documented default)
  • Flute divisor: 0.33 1 / flutes (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Chip load = programmed feed rate ÷ spindle speed × flute divisor.
  • feed per revolution before flute divisor works out to 0 in / tooth at these inputs, and this is the headline figure for the scenario.
  • Raw ratio works out to 0.01 value at these inputs.
  • Conversion factor works out to 0.33 x at these inputs.
  • spindle speed works out to 8,000 value at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where feed rate sits at 96 in / min and the headline result is 0 in / tooth, this scenario comes in 50% below the baseline at 0 in / tooth.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to feed rate, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It is a geometric calculation only; it does not account for radial chip thinning at light stepovers, so at low radial engagement the actual chip is thinner than this number and you can feed faster.

Results at a glance

  • feed per revolution before flute divisor: 0 in / tooth (headline result)
  • Raw ratio: 0.01 value
  • Conversion factor: 0.33 x
  • spindle speed: 8,000 value

Run it with your numbers

  • To rerun this with your own numbers, open the live Chip Load calculator, set feed rate to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.