Engineering Calculators
A complete machine-shop calculation suite — 57 interactive tools covering milling, turning, holemaking, tapping, balancing, GD&T and shop reference charts. These calculations are based on theoretical values and are intended for planning purposes; not precise projections of cutting forces. Actual results will vary. Verify against your machine, tooling and material documentation.
Milling Calculators
Speeds, feeds, chip load and engagement for end mills, face mills, slotting and plunge milling.
Turning Calculators
Lathe work — cutting speed, feed, machining time and power for OD/ID turning.
Holemaking & Threading
Drilling, reaming, countersinking, tapping speeds and tap drill size charts.
Material Removal, Power & Cost
Metal removal rate, machining power & torque, surface finish and tooling cost justification.
Balancing
ISO 21940 balance quality grades, permissible residual unbalance and correction mass.
Shop Reference & GD&T
Bolt circle coordinates, true position, hardness conversion and inch/metric charts.
Method notes
Speeds and feeds follow the standard definitions n = Vc·1000/(π·D) and vf = fz·z·n. Power estimates use the unit power method (material-specific horsepower per unit metal removal rate). Balancing follows ISO 21940 (formerly ISO 1940) grade definitions. Tap drill sizes use the standard 1.299038 × percentage × pitch formula at a 75% default engagement. Hardness equivalents follow ASTM E140-type tables for non-austenitic steels.