MACHINING PARAMETERS

Speeds, Feeds & Cutting Calculations

Spindle Speed (n)

Vc Cut Speed
m/min
D Diameter
mm
n Result
rpm
n = (Vc × 1000) / (π × D)

Cutting Speed (Vc)

D Diameter
mm
n Spindle
rpm
Vc Result
m/min
Vc = (π × D × n) / 1000

Feed Rate (Vf)

fz Feed/Tooth
mm/tooth
z Teeth
flutes
n Spindle
rpm
Vf Result
mm/min
Vf = fz × z × n

Feed per Tooth (fz)

Vf Feed Rate
mm/min
z Teeth
flutes
n Spindle
rpm
fz Result
mm/tooth
fz = Vf / (z × n)

Avg Chip Thickness (hm)

fz Feed/Tooth
mm/tooth
ae Radial DOC
mm
D Diameter
mm
hm Result
mm
hm = fz × (ae/D) × (360 / arccos(1 - 2ae/D))

Material Removal Rate (Q)

ae Radial DOC
mm
ap Axial DOC
mm
Vf Feed Rate
mm/min
Q Result
cm³/min
Q = (ae × ap × Vf) / 1000

Surface Finish (Ra)

fz Feed/Tooth
mm/tooth
r Nose Radius
mm
Ra Result
μm
Ra = (fz² × 1000) / (32 × r)

Tap Drill Size

D Major Dia
mm
P Pitch
mm
% Thread %
%
d Drill Size
mm
d = D - (P × %thread / 76.98)

Material Cutting Speeds (Vc) Reference

Aluminium HSS: 150-300, Carbide: 300-600 m/min
Mild Steel HSS: 25-35, Carbide: 100-200 m/min
Stainless 304 HSS: 15-25, Carbide: 60-120 m/min
Cast Iron HSS: 20-30, Carbide: 80-150 m/min
Brass HSS: 100-200, Carbide: 200-400 m/min
Titanium HSS: 10-20, Carbide: 40-80 m/min
Plastics HSS: 100-300, Carbide: 200-500 m/min
Tool Steel HSS: 10-20, Carbide: 50-100 m/min

Common Metric Tap Drills (75% Thread)

M3×0.5 drill 2.5mm
M4×0.7 drill 3.3mm
M5×0.8 drill 4.2mm
M6×1.0 drill 5.0mm
M8×1.25 drill 6.8mm
M10×1.5 drill 8.5mm
M12×1.75 drill 10.2mm
M16×2.0 drill 14.0mm

Surface Finish Guide

Ra 0.4 Mirror finish, lapping
Ra 0.8 Fine grinding, honing
Ra 1.6 Precision machining
Ra 3.2 Good machined finish
Ra 6.3 Normal machining
Ra 12.5 Rough machining

Pitch Circle Diameter (PCD) Hole Coordinates

Enter values above to calculate coordinates

Common PCD Patterns

4×100 VW, Audi, BMW (older)
5×114.3 Honda, Toyota, Nissan
5×120 BMW, Land Rover
6×139.7 Toyota trucks, Mitsubishi
M8 flange PCD 70mm, 4 holes
M10 flange PCD 85mm, 4 holes