Machining Calculator
Milling, turning, chip thinning, MRR, cycle time, and cost comparison. Each calculation only asks for the inputs it actually needs.
Milling
Choose tool type and what you want to calculate.Turning
Speed/feed, DOC, passes, MRR, and in-cut time.Compare two processes
Cycle-time comparison first. Cost analysis is optional.Process A
Process B
Optional: cost per part & annual savings
Process A tooling
Process B tooling
Reference
SFM ↔ RPM
RPM = (SFM × 12) / (π × D)
SFM = (π × D × RPM) / 12
Milling feed
IPM = RPM × Z × IPT
IPT = IPM / (RPM × Z)
Turning feed
IPM = RPM × IPR
IPR = IPM / RPM
Milling MRR
MRR = ae × ap × IPM
Turning MRR
MRR = 12 × SFM × IPR × radial DOC
Turning DOC
Radial DOC = programmed diameter/X change ÷ 2
In-cut time
Minutes = total cutting travel / IPM
Radial chip thinning
Kr = √[1 − (1 − 2ae/D)²]
hmax ≈ IPT × Kr × sin(κr)
What the parameters mainly affect
SFMPrimarily heat, wear rate, and productivity.
IPT / IPRChip thickness and cutting force. Too low can rub; too high can overload the edge.
DOC / ap / aeEngagement, force, and MRR. Turning MRR uses radial DOC.
Chip thinningAt light radial engagement, actual chip thickness is lower than programmed IPT.
Simple troubleshooting reminders
Long stringy turning chipsFeed/IPR is often too low for the chipbreaker.
Rapid flank wearOften points toward too much speed/SFM or insufficient wear resistance.
ChippingCheck feed, DOC, interruptions, rigidity, runout, and grade toughness.
Rubbing / work hardeningFeed may be too light, especially in stainless and nickel alloys.