Avanzamento per dente (fz) - Feed per Tooth (fz)

Feed rate is the linear velocity at which the cutting tool advances through or along the workpiece. In milling, it is commonly measured in millimeters per minute (mm/min) or inches per minute (IPM). In turning and drilling, feed is often expressed as feed per revolution (mm/rev or IPR).

Milling feed rate is calculated using the formula: Feed Rate = Spindle Speed (RPM) × Number of Flutes (Z) × Chip Load per Tooth (fz). For example, a 4-flute end mill running at 3,000 RPM with a chip load of 0.05 mm/tooth produces a feed rate of 3,000 × 4 × 0.05 = 600 mm/min.

Chip load is the physical thickness of material removed by each individual cutting flute as it passes through the workpiece. Maintaining the proper chip load prevents tool rubbing (if feed is too low) or tool breakage and excessive deflection (if feed is too high).

Feed rate is the total linear velocity of the machine axis (e.g. 600 mm/min or 25 IPM). Chip load is the microscopic thickness of cut taken by each tooth (e.g. 0.05 mm or 0.002 in). Chip load is a function of feed rate, spindle RPM, and cutter flute count.

Feed per revolution (fn) is the linear distance the tool advances for one complete 360-degree rotation of the spindle. It is the primary feed parameter in lathe turning and drilling, where multi-tooth chip distribution does not apply in the same manner as milling.

In metric units: RPM = (1,000 × Vc) / (π × Tool Diameter in mm). In imperial units: RPM = (12 × SFM) / (π × Tool Diameter in inches), commonly approximated as (SFM × 3.82) / Diameter.

SFM is the linear surface cutting speed at the outer perimeter of the cutting tool in feet per minute. It reflects how fast the cutting edge shears the material and determines cutting zone temperatures and tool wear rates.

Yes, in milling. Because each cutting flute shears a chip during each revolution, doubling the number of flutes doubles the total material advancement rate at the same chip load and RPM (Feed Rate = RPM × Flutes × Chip Load).

Material Removal Rate measures the volume of metal or material removed per unit of time, typically expressed in cubic centimeters per minute (cm³/min) or cubic inches per minute (in³/min). In milling, basic rectangular MRR = Axial Depth (ap) × Radial Width (ae) × Feed Rate.

When radial width of cut (stepover) is less than 50% of the cutter diameter, the cutting flute exits before reaching full engagement thickness. This results in an actual chip thickness smaller than the programmed feed per tooth. A radial chip thinning factor (RCTF) compensates by increasing the programmed feed rate to preserve optimal chip formation and prevent work-hardening.

The calculated feed rate is a mathematical starting point. You must evaluate your specific machine rigidity, spindle horsepower, workholding rigidity, tool overhang, workpiece hardness, and coolant capabilities before applying cutting parameters.

Yes. You can switch between Metric (mm, mm/min, m/min, cm³/min) and Imperial (in, IPM, SFM, in³/min) at any time. Entered values are converted accurately without loss of engineering context.