BSF Imperial Machine Screws

BSF (British Standard Fine) machine screws are widely used in classic automotive work, vintage machinery, agricultural equipment, steam engines and restoration engineering. Their fine 55° Whitworth-profile thread provides strong clamping force and excellent resistance to vibration.

Typical uses include engine rebuilds, gearbox work, agricultural machinery repair, heritage equipment maintenance and any application where compatibility with original BSF fasteners is essential. BSF screws remain common in older British vehicles and machinery, making them vital for restoration and service work.

British Standard Fine was introduced alongside the Whitworth system to provide a finer-pitch alternative for applications requiring greater strength in steel components. BSF uses the same 55° thread angle as BSW but with a finer pitch, offering improved tensile performance and better holding power in hard materials.