Free Cutting Speed Calculator
Calculate the spindle RPM required for a desired cutting speed and workpiece diameter on a lathe or mill.
Required Spindle Speed
637 RPM
Required Spindle Speed vs Cutting Speed (Vc)
Cutting Speed to Spindle RPM
Cutting speed is the velocity at which the tool edge moves relative to the workpiece surface.
Formula
N = 1000 Vc / (pi D)
where Vc is the desired cutting speed in m/min and D is the workpiece (or cutter) diameter in mm. The factor 1000 converts metres to millimetres. Recommended cutting speeds depend on the tool material and workpiece material combination.
Example Calculation
Turning a 50 mm diameter steel bar at 100 m/min cutting speed.
- 01N = 1000 x 100 / (pi x 50)
- 02N = 100,000 / 157.08 = 637 RPM
Frequently Asked Questions
Learn More
Beam Stress Calculation Guide: From Theory to Practice
Learn how to calculate beam stress step by step. Covers bending stress, shear stress, the flexure formula, stress distributions, and practical design checks for structural beams.