Cutting Speed Calculator (SFM)

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This cutting speed calculator determines surface feet per minute (SFM), which represents the speed at which the cutting tool engages the material.

SFM depends on tool diameter and spindle speed (RPM).

Formula:

SFM = (π × Diameter × RPM) / 12

Higher SFM is typically used for softer materials like aluminum, while lower SFM is used for harder materials like steel.

Example:

If RPM = 1000 and diameter = 1 inch,

SFM ≈ (3.1416 × 1 × 1000) / 12 ≈ 262 SFM.

When to use this calculator:

Use this calculator to determine cutting speed based on tool diameter and RPM.

Machining tip:

Maintaining proper cutting speed improves surface finish and prevents excessive tool wear.

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