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Algorithms for Saw Blades

Abbreviations and Symbols

= Pi or 3.14D = Diameter of toolvf = Feed rate of materialsZ = Chip load per toothn = Spindle Speed in Revolutions per

minute (RPM)p = Pitch or distance from tooth-to-toothzc = Effective teeth to make a kerf cut

(Example: A 60 tooth ATB is zc=30)vc = Rim speed (Cutting speed on

periphery)z = Number of Teeth in the tool

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Chip Load (fz) Chart for Woodworking Tools

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Calculating the Chip Load (sz)

sZ = Chip load per toothz = Number of teeth in tooln = Spindle Speed in Revolutions per minute

(RPM)vf = Feed rate

English: Enter in feet per minuteMetric: Enter in meters per minute

zc = Number of teeth to make a complete kerf cut

English: Chip load result is in thousandths of an inch (in.)sZ = (vf x 12) ÷ (z x n) x zc

Metric: Chip load result is in millimeters (mm)sZ = (vf x 1000) ÷ (z x n) x zc

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Calculating the Pitch (p)

p = Pitch or distance from tooth-to-tooth = 3.14D = Diameter of the tool

English: Enter diameter in inchesMetric: Enter diameter in mm

z = Number of teeth in the tool

English: Pitch result is in thousandths of an inch (.000”)p = ( x D) ÷ z

Metric: Pitch result is in millimeters (mm)p = ( x D) ÷ z

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Calculating the # of teeth Required (z)

z = Number of teeth = 3.14D = Diameter of the tool

English: Enter diameter in inchesMetric: Enter diameter in mm

p = Pitch or distance desired from tooth-to-toothEnglish: Enter pitch in inches

Metric: Enter diameter in mm

z = ( x D) ÷ p = Number of teeth required

z = ( x D) ÷ p = Number of teeth required

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Recommended Rim Speed

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Calculating the Rim Speed (vc)

vc = Rim speed (Cutting speed)D = Diameter of the tooln = Spindle Speed in Revolutions per minute

(RPM) = 3.14

English: Rim speed measured in feet per second (ft./sec.)vc = (D x x n) ÷ (12x 60) or (.262 x D x n) ÷

60English: Rim speed measured in feet per minute (ft./min.)vc = (D x x n) ÷ 12 or .262 x D x n

Metric: Rim speed measured in meters per second (m/s)vc = (D x x n) ÷ (1000 x 60)Metric: Rim speed measured in meters minute (m/min.)vc = (D x x n) ÷ 1000

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Calculating the Feed Rate (vf)

vf = Feed rate required (Feet or Meters/Minute)

fz = Desired or recommended chip loadEnglish measurement in thousandths of an

inchMetric measurement in mm

n = Spindle Speed in Revolutions per minute (RPM)

z = Number of teeth in the toolzc = Effective teeth to make a kerf cut

English: Feed rate measured in feet per minute (ft./min.)vf = (fz x z x n) ÷ 12

Metric: Feed rate measured in meters per minute (m/min.)vf = (fz x z x n) ÷ 1000

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Calculating the Spindle Speed RPM (n)

n = Spindle Speed in Revolutions per minute (RPM)

vc = Rim speed (Cutting speed on periphery)English: Enter in feet per minute

D = Diameter of the toolEnglish: Enter in inches

n = (3.82 x vc ) ÷ D

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