Shop calculator
Cutting RPM for mill and lathe
Pick the material, HSS or carbide, diameter and number of teeth. CutRPM gives starting spindle speed and feed — then you tune it to the machine.
Spindle speed
2,426
RPM
- Table / carriage feed
- 29.1 IPM
- Surface speed
- 318 SFM
- IPT
- 0.0030
- Cycle time
- Set length
Workpiece
Shop standard. Flood coolant. Watch stringy chips on turning.
Aluminum
Steel
Stainless
Cast iron
Non-ferrous
Titanium & nickel
Plastics & wood
Tooling
Suggested 0.0030 IPT
Cutting speed
Carbide handbook range for 1018
Cut length
Optional. Used to estimate cycle time from table / carriage feed.
How this is calculated
On a mill the cutter spins. RPM is set from cutter diameter and recommended surface speed for the material + HSS/carbide pairing.
Spindle RPM
RPM = (CS × 12) / (π × D)
2,426 = (318 × 12) / (π × 0.5)
Table feed
IPM = RPM × Z × IPT
29.1 = 2,426 × 4 × 0.0030
Shop rule of thumb for inches: RPM ≈ (SFM × 3.82) / D. Values here use exact π. These are starting numbers — listen to the cut, watch the chip, and confirm against the tool maker.
Saved setups
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