Shakeproof washers prevent nuts and bolts from loosening due to vibration. They feature sharp teeth that bite into the mating surface and the fastener head.
Internal Tooth Washers
- Design: Teeth extend inward along the inner diameter.
- Appearance: Smooth, clean outer edge.
- Best For: Small-head fasteners like pan head or cheese head screws.
- Visual Profile: Hidden completely under the screw head after tightening.
- Biting Surface: Contacts the smallest diameter of the fastener head.
External Tooth Washers
- Design: Teeth extend outward along the outer diameter.
- Appearance: Star-like, spiked outer edge.
- Best For: Large-head fasteners like hex bolts or washer-head screws.
- Maximum Grip: Teeth sit further from the centre, providing higher torsional resistance.
- Surface Contact: Covers a larger surface area on the mating material.
Choose Internal When:
- Space is tight: Preventing the washer from catching on nearby parts.
- Aesthetics matter: Keeping the finished assembly looking neat and scratch-free.
- Electrical grounding: Scraping paint off small chassis holes for a solid ground connection.
Choose External When:
- Maximum vibration resistance: High-vibration machinery requiring maximum holding power.
- Softer materials: Distributing locking pressure across a wider surface area.
- Standard hex bolts: Matching the wide flange of standard industrial fasteners.
Materials and Selection
- Steel: Zinc-plated steel provides standard indoor corrosion resistance.
- Stainless Steel: Best for outdoor, marine, or chemical environments.
