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Request A ToolBasic Cutting Speed Calculator
Calculate the surface speed produced by a known diameter and spindle setting. This reverses the RPM calculation and helps you check an existing setup against the units used in its tooling documentation. Enter the diameter at the cut and the RPM actually used. This matters when a spindle cap prevents the machine from reaching the original theoretical speed.
Used For
Check cutting diameter and actual spindle RPM.
Formula
Vc in m/min = π × D in mm × RPM ÷ 1000. SFM = π × D in inches × RPM ÷ 12.
Cutting Speed Basic
Enter the values you know. The result is calculated in your browser.
Calculation only. Verify toolmaker data, material grade, engagement, machine limits, workholding and actual cutting conditions before production.
Advanced Cutting Speed Calculator
Review the additional variables shown in this tool.
Cutting Speed
Enter the values you know. The result is calculated in your browser.
Calculation only. Verify toolmaker data, material grade, engagement, machine limits, workholding and actual cutting conditions before production.
Check The Surface Speed At A Known RPM
- Select the length units used for the cutting diameter.
- Enter the cutter diameter for conventional milling or drilling, or workpiece diameter for conventional turning.
- Enter actual RPM and calculate surface speed. The advanced ceiling field lets you compare a limited spindle setting.
Formula And Units
Vc in m/min = π × D in mm × RPM ÷ 1000. SFM = π × D in inches × RPM ÷ 12.
Illustrative Calculation
A 10 mm cutting diameter at 6,000 RPM corresponds to 188.5 m/min. A 20 mm diameter at the same RPM corresponds to 377.0 m/min. The RPM did not change, but the edge speed doubled.
Use The Cutting Diameter
A milling cutter, drill and turning workpiece can all use this surface-speed relationship when the relevant diameter is known. The equation does not make their cutting-data ranges interchangeable.
Manufacturer Data And Threading
Read the source for the exact tool series, material condition and operation. A threading recommendation also depends on pitch and tool geometry. A brand name or generic material family alone is not enough to select a cutting speed.
Check the formula reference or report a result that does not match your calculation.
Calculation Process With Example Values
Illustrative arithmetic only. Select cutting inputs from the applicable tool and material reference.
| Step | Substitution | Result |
|---|---|---|
| Cutting Speed | π × 10 × 6,000 ÷ 1000 | 188.50 m/min |
Read The Result At The Diameter Entered
The output describes the circumference speed at one diameter and RPM. It does not track a changing turning profile or select a threading recommendation. Use the turning workspace for the feed convention and diameter checks associated with lathe work.
Formula reference: Sandvik Coromant milling formulas and definitions. Use the exact tool supplier for recommended cutting values.
Applications And Related Calculation Workflows
Cutting Speed For Milling, Drilling And A Lathe
For a conventional milling or drilling speed calculation, use the cutting diameter of the rotating tool. For conventional lathe turning, use the workpiece diameter at the cut. The metric cutting speed relationship is π × diameter in millimetres × RPM ÷ 1000. A changing turning diameter changes surface speed at fixed RPM; a constant-surface-speed control is a different programming condition.
End Mill And Thread Cutting Speed
An end mill cutting speed check converts the entered diameter and RPM into surface speed; it does not choose the toolmaker recommendation. A thread cutting speed check also needs an operation-specific source because threading geometry and engagement differ from general turning. For synchronized tapping feed, use the pitch and RPM calculation rather than treating surface speed as linear feed.
Cross-Checking A Sandvik Cutting Speed Reference
If you are checking Sandvik cutting data, identify the exact tool series, insert or cutter, operation and material condition in the original source. Use this independent cutting tool speed calculator to reproduce the surface-speed relationship from diameter and RPM. It does not connect to Sandvik product data, select a grade or replace the manufacturer tool recommendation.
Cutting Speed Questions
Is Cutting Speed The Same As Table Feed?
No. Cutting speed is the speed at the cutting circumference. Milling table feed also depends on tooth feed and effective teeth, so the two outputs use different relationships.
Can This Check A Manufacturer RPM Recommendation?
Yes, when the stated diameter and units are known. It reproduces surface speed from RPM; it does not confirm that the recommendation applies to a different tool series or material condition.
Help Improve This Resource
Report An Error
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