Tooling Pro Tooling Pro

  • Home
  • CBN & PCD Inserts
  • Ceramic Inserts
  • Chuck Jaws
  • Calculators
  • Special Services
  • Contact us
  • CBN Technical Information
  • CBN Machining Videos
  • Drilling Calculators
  • Milling Calculators
  • Turning Calculators
  • Machinist Programmer Calculators
  • Drill and Tap Charts
  • Machining Formulas
  • Home
  • CBN & PCD Inserts
    • CBN Technical Information
    • CBN Machining Videos
  • Ceramic Inserts
  • Chuck Jaws
  • Calculators
    • Drilling Calculators
    • Milling Calculators
    • Turning Calculators
    • Machinist Programmer Calculators
    • Drill and Tap Charts
    • Machining Formulas
  • Special Services
  • Contact us

Machining Formulas 

Cutting Speed Formulas Lathe or Mill

(RPM = Revolutions Per Minute)  3.82 x SFM ÷ Diameter 

(SFM = Surface Feet Per Minute )  0.262 x Diameter ( Tool or Stock ) x RPM


Metric Conversion

(SFM to Surface Meters Per Minute) SFM x .3048

(Surface Meters Per Minute to SFM) SMPM x 3.2808399


Turning & Boring Cubic Inches per Minute

MMR =12 × DOC × Feed × SFM


Milling Feed Rate Formulas

Inches Per Minute (IPM) = FPT x T x RPM

Feed Per Revolution (FPR) = IPM ÷ RPM

Feed Per Tooth (FPT) = IPM ÷ (RPM x T)


Metric Conversion

Convert Inches Per Revolution (IPR) to Inches Per Minute (IPM) = IPR x RPM

Convert Inches Per Minute (IPM) to Inches Per Revolution (IPR) = IPM ÷ RPM


Convert Inches Per Revolution (IPR) to Millimeters Per Revolution (MMPR) = IPR x 25.40

Millimeters to Inches = Millimeters x .03937 = Inches

Inches to Millimeters = Inches x 25.4 = Millimeters

Meters to Inches = Meters x 39.37 = Inches

Inches to Meters = Inches x .0254 = Meters

Meters to Feet = Meters x 3.2808 = Feet

Feet to Meters = Feet x .3048 = Meters

Meters to Yards = Meters x 1.0936 = Yards


Milling Formulas

(CTM = Time Cutting Time in Minutes)  L ÷IPM

(CTS = Time Cutting Time in Seconds)  L ÷IPM x 60

(IPM = Inches per Minute)  RPM x IPT x # of Teeth (flutes)

(MRR = Metal Removal Rate /Cubic Inches per Minute)  W x D x IPM


 These calculations are based upon theoretical values and are only intended for planning purposes. Actual results will vary. No responsibility from Tooling Pro is assumed. 

Make a free website with Yola