Full Nuts

About Full Nuts

Full nuts, also known as hexagon full nuts or hex nuts, are essential fastening components used across countless applications in construction, engineering, automotive, and general assembly work. Unlike their thinner counterparts (lock nuts or half nuts), full nuts feature a standard height typically equal to their thread diameter, providing maximum thread engagement and superior load distribution. This makes them the go-to choice for applications requiring reliable, long-lasting fastening solutions where vibration resistance and structural integrity are paramount.

Our range of full nuts includes premium options from trusted brands like SIRIUS and SEALEY, available in various materials and finishes to suit different environments and requirements. Whether you need stainless steel A2 304 or A4 316 grades for corrosion-resistant applications, bright zinc plated steel for general purpose use, or hot-dip galvanised variants for outdoor installations, you'll find professional-grade full nuts designed to meet DIN 934 and ISO 4032 standards. These nuts are manufactured to precise tolerances, ensuring consistent thread quality and reliable performance in demanding applications.

Full nuts are supplied in metric thread sizes ranging from small M3 fasteners through to heavy-duty M24 and beyond, accommodating everything from delicate electronic assemblies to structural steelwork. The hexagonal design allows for efficient tightening with standard spanners, socket sets, or powered impact tools, making them practical for both workshop fabrication and on-site installation work.

Jargon Buster

• DIN 934: The German industrial standard specifying dimensions, tolerances, and mechanical properties for hexagon full nuts. DIN 934 nuts are widely recognised throughout Europe and have largely been superseded by the equivalent ISO 4032 standard, though both terms remain commonly used.
• A2 and A4 Stainless Steel: Grade classifications for stainless steel fasteners. A2 (304 grade) offers good corrosion resistance for most indoor and many outdoor applications, whilst A4 (316 grade) contains molybdenum for superior resistance to marine environments and chemical exposure.
• Bright Zinc Plated (BZP): An electroplated coating that provides a shiny silver finish and moderate corrosion protection, suitable for indoor use and dry environments. The most economical protective finish for general purpose applications.
• Hot-Dip Galvanised: A coating process where steel fasteners are immersed in molten zinc, creating a thick protective layer ideal for outdoor structural applications, exposed steelwork, and agricultural environments where enhanced corrosion resistance is essential.
• Thread Pitch: The distance between adjacent threads, measured in millimetres for metric fasteners. Standard (coarse) pitch is most common, whilst fine pitch threads offer increased precision and better vibration resistance in specific applications.
• Property Class: A numerical designation (such as 8.8 or 10.9) indicating the tensile strength and yield strength of steel nuts and bolts, ensuring matched fastener assemblies meet specified load requirements.

Who Uses Full Nuts?

Full nuts are fundamental fastening components used across virtually every trade and industry:

• General Builders and Construction Workers: For structural connections, framework assembly, and securing building components
• Mechanical Engineers and Fitters: Machine assembly, equipment installation, and maintenance work
• Steel Erectors and Fabricators: Structural steelwork connections and metalwork fabrication
• Automotive Mechanics and Vehicle Technicians: Car repairs, modifications, and restoration projects
• Electricians: Securing electrical enclosures, cable tray installations, and conduit systems
• Plumbers and Heating Engineers: Pipe bracket installations and equipment mounting
• Maintenance Engineers: Equipment repairs and plant maintenance across all sectors
• Shopfitters and Joiners: Fixture installations and structural connections
• DIY Enthusiasts and Home Improvers: General repairs, garden projects, and home improvement tasks
• Agricultural Workers: Farm machinery repairs and equipment maintenance

How to Choose the Right Full Nuts

Selecting appropriate full nuts requires consideration of several key factors to ensure reliable, long-lasting fastening:

Material and Finish: Choose based on environmental conditions. Stainless steel A2 (304) suits most indoor and general outdoor applications, whilst A4 (316) is preferred for coastal areas, chemical plants, and food processing environments. Bright zinc plated steel offers economical protection for dry indoor use, whereas hot-dip galvanised nuts provide superior corrosion resistance for external structural work and agricultural applications.

Thread Size and Pitch: Match the nut thread precisely to your bolt or threaded rod. Metric threads are standard in the UK, with M6, M8, M10, and M12 being most common for general applications. Always verify thread pitch—whilst coarse pitch is standard, some applications require fine pitch threads for better vibration resistance or precise adjustment.

Property Class Compatibility: Ensure nuts match or exceed the property class of bolts in load-bearing applications. An 8.8 property class bolt requires a minimum grade 8 nut for proper load transfer, whilst 10.9 high-tensile bolts need corresponding grade 10 nuts.

Standards Compliance: For structural and critical applications, specify nuts manufactured to recognised standards such as DIN 934 or ISO 4032. These standards guarantee dimensional accuracy, thread quality, and mechanical properties essential for safe, reliable fastening.

Quantity Requirements: Full nuts are typically supplied in various pack quantities, from small assortment boxes for occasional use to bulk packs for regular tradespeople and contractors. Consider your project requirements and future needs when ordering.

Popular Accessories

Full nuts work as part of complete fastening systems. Consider these complementary products:

• Hex Head Bolts and Set Screws: The primary fasteners that full nuts secure onto
• Washers: Plain washers distribute load and protect surfaces; spring washers provide vibration resistance; penny washers suit timber applications
• Lock Nuts and Nyloc Nuts: Self-locking alternatives for vibration-prone applications
• Threaded Rod and Studding: For creating custom-length fasteners and adjustable connections
• Socket Sets and Spanners: Essential tools for installation and removal, including ratchet sets and impact socket sets
• Thread Gauges: For accurately identifying thread sizes and pitch
• Thread Cutting Taps: For creating threaded holes in materials
• Anti-Seize Compounds: Prevent galling on stainless steel fasteners and ease future disassembly
• Threadlocking Compounds: Chemical adhesives that secure nuts against vibration loosening

Frequently Asked Questions

What's the difference between a full nut and a lock nut?

A full nut (also called a standard hex nut) has a height approximately equal to its thread diameter, providing maximum thread engagement and load distribution. Lock nuts are typically thinner and incorporate features like nylon inserts or deformed threads to resist loosening from vibration. Full nuts are stronger and better for static loads, whilst lock nuts excel in applications subject to vibration.

Can I use stainless steel nuts with zinc plated bolts?

Whilst mechanically compatible, mixing stainless steel nuts with zinc plated or mild steel bolts can cause galvanic corrosion when moisture is present, as the dissimilar metals create an electrochemical reaction. For best results, use matched materials—stainless with stainless, or zinc plated with zinc plated. If mixing is unavoidable, apply anti-seize compound and use in dry environments only.

How tight should I fasten full nuts?

Proper tightening depends on thread size, material, and application. For critical structural applications, follow torque specifications provided by engineers or consult torque charts for specific property classes. Over-tightening can strip threads or cause fastener failure, whilst under-tightening may result in loose connections. For general applications, tighten until components are firmly secured without excessive force—experienced tradespeople develop a feel for appropriate tightness.

Are galvanised nuts suitable for use with treated timber?

Hot-dip galvanised fasteners are ideal for use with timber, including pressure-treated varieties. The thick zinc coating resists corrosion from preservative chemicals and moisture commonly found in outdoor timber structures. This makes galvanised full nuts perfect for decking, fencing, pergolas, and garden structures. Avoid using bright zinc plated or bare steel fasteners in these applications, as they'll corrode rapidly.

What does the M size mean on metric nuts?

The "M" designation indicates metric thread sizing, with the number following representing the nominal diameter in millimetres. For example, an M10 nut fits onto an M10 bolt with a 10mm nominal thread diameter. This standardised system ensures compatibility across manufacturers and makes selecting correct sizes straightforward. Always match M sizes exactly—an M10 nut will not fit an M12 bolt and vice versa.