Set Screws

About Set Screws

Set screws, also known as fully threaded bolts or machine screws, are essential fastening components featuring external threads along their entire shaft and a hexagonal head for tightening with spanners or sockets. MyToolShed.co.uk stocks a comprehensive range of set screws in various materials, grades and sizes to suit demanding applications across construction, engineering and general fabrication work. From stainless steel variants for corrosion resistance to high tensile grade 8.8 and 10.9 options for heavy-duty structural connections, our collection covers the fastening requirements of professional tradespeople and serious DIY enthusiasts.

Available from trusted brands including Sirius, Timco and Sealey, the set screws at MyToolShed come in zinc plated, galvanised, brass and stainless steel finishes. Whether you need individual sizes for specific projects or convenient assortment kits containing multiple sizes with matching nuts and washers, you'll find quality fasteners engineered to British and European standards for reliable, long-lasting performance.

Applications

Set screws are versatile fasteners used across numerous trades and industries:

• Construction and building: Structural steelwork, timber frame connections, cladding systems and general fabrication
• Mechanical engineering: Machinery assembly, equipment mounting and precision engineering applications
• Plumbing and heating: Securing pipework brackets, radiator mountings and boiler installations
• Automotive and marine: Vehicle repairs, boat building and outdoor equipment requiring corrosion-resistant fasteners
• Manufacturing: Production line equipment, jigs and fixture assembly
• Maintenance and repair: General purpose fastening across facilities management and property maintenance

Choosing The Right Set Screws

Selecting appropriate set screws depends on several critical factors:

Material and finish: Stainless steel A2 (304) offers excellent corrosion resistance for outdoor and damp environments, whilst A4 (316) provides superior marine-grade protection. Zinc plated and galvanised steel deliver cost-effective corrosion protection for general applications. Brass set screws resist corrosion and avoid magnetic interference in specialist installations.

Tensile grade: Grade 8.8 high tensile set screws suit most structural applications requiring reliable strength. Grade 10.9 provides even higher tensile strength for critical load-bearing connections where maximum fastening force is essential.

Size and thread: Ensure correct diameter and length for your application, with thread pitch matching corresponding nuts and tapped holes. Common sizes range from M5 through M10 for general work, with larger diameters available for heavy-duty applications.

Assortments versus individual sizes: Starter assortments from Sealey provide convenient variety for workshops and service vehicles, whilst bulk quantities of individual sizes suit specific projects with known requirements.

Frequently Asked Questions

What's the difference between grade 8.8 and grade 10.9 set screws?

The numbers indicate tensile strength ratings. Grade 8.8 has a minimum tensile strength of 800 MPa and is suitable for most general engineering and construction applications. Grade 10.9 offers higher strength at 1000 MPa minimum, making it ideal for critical load-bearing connections requiring maximum fastening security.

Can I use zinc plated set screws outdoors?

Zinc plated set screws provide basic corrosion protection suitable for dry indoor environments and limited outdoor exposure. For permanent outdoor installations or damp conditions, choose galvanised, stainless steel A2 or A4 variants which offer significantly better long-term corrosion resistance.

Do set screws require washers?

Whilst not always essential, washers distribute load more evenly across surfaces, prevent damage to softer materials and reduce the risk of loosening under vibration. For critical structural connections or when fastening into timber or softer metals, using washers alongside set screws and nuts is recommended best practice.