CNC Academy · Cutting
CNC Speeds and Feeds: Turn Settings Into a Test Plan
Speeds and feeds are not a magic number. They are a starting relationship between the bit, material, machine, workholding, and the finish you need—then refined through a controlled test.
Visual lesson
The chip-load loop
Inputs
- Bit + flute count
- RPM
- Material and depth
Shop process
Choose a feed rate → inspect chips and edge
Result
Documented settings for that setup
Start with the whole cutting system
Tool diameter, flute count, material, hold-down, spindle power, depth, and finish expectation all change what a sensible starting point looks like.
Watch the cut, not only the screen
Inspect chip formation, heat, noise, chatter, tearout, fuzzing, and edge quality. Change one variable at a time so you can tell what actually improved the result.
Build a shop-specific settings library
Record the bit, material, RPM, feed, depth of cut, stepover, hold-down method, and result. Your own successful settings are more useful than a generic chart.
On the machine or at the bench
Use this checklist before you run.
- Identify the bit, flute count, material, and operation.
- Start from manufacturer guidance or a conservative calculator result.
- Test on matching stock before production.
- Inspect chips, sound, heat, and edge quality.
- Record the proven setting with the full setup context.
Use the tool