► Cup Head Bolts

Cup Head Bolts – Smooth-Finish Fasteners for Timber & Structural Framing Cup head bolts, also known as carriage bolts, are used to fasten timber, steel, or composite materials where a smooth, tamper-resistant finish is required. These bolts feature a rounded dome head with a square neck underneath that locks into...

Cup Head Bolts – Smooth-Finish Fasteners for Timber & Structural Framing

Cup head bolts, also known as carriage bolts, are used to fasten timber, steel, or composite materials where a smooth, tamper-resistant finish is required. These bolts feature a rounded dome head with a square neck underneath that locks into the material when tightened. Ideal for timber decks, playgrounds, fencing, & structural framing, cup head bolts provide secure fastening without protruding edges.

What’s in This Collection:
Galvanised cup head bolts for outdoor timber construction
Stainless steel carriage bolts for corrosion resistance
Smooth dome heads for safety & aesthetic appeal
Square shank for anti-rotation in timber
Supplied with nuts & washers for full fastening sets
Sizes from M6 to M20 in various lengths

Clean, Safe Fastening for Outdoor & Timber Projects

Built for strength, safety, & clean finishes, our cup head bolts are a go-to choice for outdoor projects, structural joinery, & timber framing. Whether you're assembling a pergola or securing structural beams, these bolts hold strong—without the sharp edges.

Rounded dome head for tamper resistance & safety

Anti-spin square neck for easy installation

Available in trade packs with washers & nuts

Frequently Asked Questions

The square neck embeds into the timber to prevent the bolt from turning while the nut is tightened—ensuring secure fastening without needing a second tool.

Yes—galvanised & stainless steel cup head bolts are corrosion-resistant, making them ideal for decks, fences, pergolas, & other outdoor structures.

They’re primarily designed for timber, but they can be used in thin metal sheeting where the square neck can bite in or where access is limited to one side.

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