How and where to use guide
HEX HEAD TIMBERFAST BLACK (BOX 50) 125mm
Typical applications
These 125mm screws are suited to structural timber connections, decking frameworks, fence post assembly, landscaping structures, and outdoor timber-to-timber joinery. The self-drilling capability makes them particularly valuable where access for pilot drilling is limited or where speed of installation is a priority. The corrosion-resistant coating makes them suitable for coastal projects, exposed exterior work, and applications subject to moisture or salt spray exposure.
- Structural timber connections and load-bearing joints
- Decking subframes and joist fixing
- Fence and gate post assembly
- Landscaping timber structures and raised beds
- Exterior cladding and weather-exposed joinery
Installation and usage
Position the screw perpendicular to the timber surface and apply steady downward pressure whilst driving with the included hex bit. The self-drilling point will penetrate most softwoods without a pilot hole; however, for hardwoods or where multiple screws are being driven close together, consider drilling a small pilot hole to reduce splitting risk. Drive the screw until the 12mm washer sits flush against the timber surface, creating even clamping pressure. Avoid over-tightening, which can strip the timber or damage the screw head.
- Use the supplied hex driver bit for consistent seating
- Maintain perpendicular angle to timber surface during installation
- For hardwoods or dense timber, pre-drill pilot holes to prevent splitting
- Tighten until washer is flush; do not over-drive
- Space screws appropriately to avoid timber splitting near edges
Limitations and maintenance
Whilst the Ruspert coating provides excellent corrosion resistance for 1000 hours in salt spray testing, these screws are not rated for use in chemically treated timber or in direct contact with concrete or masonry. The 50mm thread length means the screw is suitable for joining timbers of moderate thickness; for thicker sections or where maximum withdrawal resistance is needed, consider longer fasteners. Inspect installed screws periodically in coastal or high-moisture environments, and re-tighten if movement is detected.
- Not suitable for masonry or concrete applications
- Check compatibility with any timber treatments before installation
- Thread length of 50mm limits holding power in very thick sections
- Periodic inspection recommended in exposed or coastal locations
- Do not use in applications requiring stainless steel specification
On-site tips
Store screws in a dry location to maintain coating integrity. The hex washer head design significantly reduces the risk of cam-out compared to standard timber screws, but maintain firm downward pressure and use the correct driver bit to ensure full engagement. When working in wet conditions, allow timber to dry slightly before fastening to reduce splitting. On exposed projects, consider applying additional sealant around the screw head if maximum weather protection is required.
- Keep screws dry before use to preserve the Ruspert coating
- Ensure hex bit is fully seated in the screw head before driving
- Work in dry conditions where possible to minimise timber splitting
- The 12mm washer provides good surface contact; do not use additional washers unless specified
- Include hex driver bit in your site toolkit to avoid delays