Cutting Speed & RPM
Pick the value to solve for — the rest are your knowns.
Solve for
Material Vc reference
Carbide, general-purpose starting point — adjust for your tooling, finish and rigidity.
Readout
Spindle Speed
—
RPM
N = (12 × Vc) ÷ (π × D)
Feed Rate
Milling uses chip load per tooth; turning uses feed per revolution.
Solve for
Readout
Feed Rate
—
IPM
FR = N × flutes × chip load
Metal Removal Rate
How fast you're taking material off the part.
Readout
Metal Removal Rate
—
in³/min
MRR = Feed Rate × Width × Depth
Cycle Time
Time to run a cut, including approach and repeat passes.
Readout
Cycle Time
—
min : sec
t = passes × (length + allowance) ÷ feed rate
Cost per Component
Machine time, tooling wear, material and amortized setup — all in.
Readout
Cost per Part
—
ZAR
- Machine time—
- Tooling wear—
- Material—
- Setup (amortized)—
Tapping Speed & Feed
Thread pitch sets the feed — the spindle just has to keep up.
Solve for
Readout
Spindle Speed
—
RPM
Feed Rate
—
IPM
N = (12 × Vc) ÷ (π × D) · FR = N ÷ TPI