Convert Pound square feet to Kilogram square millimetres

Convert Pound square feet (lb·ft²) to Kilogram square millimetres (kg·mm²) instantly and accurately.

Pound square feet (lb·ft²)
Kilogram square millimetres (kg·mm²)

Conversion Formula

kg·mm² = lb·ft² × 42140.11009

About Pound square feet

The pound square foot (lb·ft²) equals ≈0.04214 kg·m², the dominant imperial unit for machine and vehicle rotational inertias. Aircraft control-surface counterbalancing, propeller blade inertia, and turbocharger rotor dynamics are specified in lb·ft²; steam turbine discs and helicopter tail-rotor assemblies: 1-10 000 lb·ft². 1 lb·ft² ≈0.04214 kg·m² = 144 lb·in² ≈0.03108 slug·ft².

About Kilogram square millimetres

The kilogram square millimetre (kg·mm²) equals 10⁻⁶ kg·m², widely used in CAD software and precision mechanical engineering. SolidWorks, CATIA, and Siemens NX report mass moment of inertia in kg·mm² for gear blanks, pulley hubs, and precision spindle assemblies. Industrial small servo motor rotors: 100-10 000 kg·mm². 1 kg·mm² = 10⁻⁶ kg·m² = 10 g·cm² = 0.01 kg·cm².

Quick Reference Table

Pound square feet (lb·ft²)Kilogram square millimetres (kg·mm²)
1 lb·ft²42140.1 kg·mm²
2 lb·ft²84280.2 kg·mm²
5 lb·ft²210701 kg·mm²
10 lb·ft²421401 kg·mm²
25 lb·ft²1053500 kg·mm²
50 lb·ft²2107010 kg·mm²
100 lb·ft²4214010 kg·mm²

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