Tufnol

Overview

Tufnol is a trade name for a range of cotton-woven and glass-woven phenolic (and epoxy) laminates manufactured in the UK and used widely in precision mechanical and electrical applications. The cotton-fabric base grades (particularly Carp Brand) are known for their exceptional machinability — producing clean surfaces, holding tight tolerances, and being free from delamination risk during machining. Tufnol is used across electrical equipment, marine engineering, food processing, and precision mechanical applications. While it shares the thermoset character of general Bakelite/phenolic laminate, Tufnol grades are manufactured to tighter quality standards and are particularly specified by name for precision machined components.

Working properties

• Machinability

  Cotton-base Tufnol grades (Carp Brand) are renowned for their machining quality. They drill, mill, and turn cleanly without delamination and hold tight tolerances. This makes Tufnol a preferred choice for precision machined electrical insulating components such as bushings, pulleys, cam followers, and spacers.

• Electrical insulation

  Tufnol provides good electrical insulation under dry conditions, suitable for a wide range of electrical equipment and switchgear applications.

• Mechanical toughness

  The woven cotton reinforcement gives Tufnol considerably better impact resistance and toughness than paper-base phenolic grades. It is less brittle and more appropriate for dynamically loaded components such as gears, cams, and pulleys.

• Moisture and wet conditions

  Cotton-base Tufnol has moderate moisture resistance, adequate for many applications but not recommended for continuously submerged or wet electrical applications. Glass-fabric grades offer better moisture resistance where this is required.

• Heat resistance

  As a phenolic thermoset, Tufnol does not soften or melt under heat. It can operate continuously at elevated temperatures typical of industrial electrical equipment.

Typical uses

• Precision machined bushings, spacers, and bearing rings in electrical equipment
• Pulleys, gears, and cam followers in food processing and light industrial machinery
• Marine electrical equipment components and insulating parts
• Electrical panel mounting plates and insulating structural components
• Jigs and fixtures requiring electrical isolation with precision dimensions

Things to confirm before ordering

• Grade — Tufnol Carp Brand (cotton fabric) for general machined components; glass-fabric grades for improved moisture resistance; confirm which is appropriate.
• Form — sheet, rod, or tube; confirm dimensions required.
• Application — confirm whether the intended use is primarily mechanical (gears, pulleys) or electrical insulating, as this guides grade selection.

How does Tufnol compare?

• Bakelite / Phenolic (paper base)

  Paper-base phenolic is cheaper but less tough and delaminate more readily during machining. Tufnol cotton-fabric grades are significantly more machinable and mechanically robust — the preferred choice for precision components.

• G10 / FR4

  G10/FR4 (glass epoxy) offers superior electrical properties and moisture resistance. For high-performance electrical insulation or wet environments, G10/FR4 is the better choice. Tufnol is preferred when machinability and mechanical toughness are the priority.