Hex Nuts

Hex nuts are six-sided fastening components designed to pair with a matching bolt or threaded rod, creating a secure joint that can handle vibration, load, and repeated assembly. In practical terms, a hex nut turns a simple bolt into a reliable clamping system. They are essential for everything from machinery frames to electrical enclosures and general fabrication.

Because their shape makes them easy to grip with standard spanners and sockets, hexagonal nuts are widely used across workshops, job sites, and production lines. In New Zealand, whether you’re sourcing hex nuts for maintenance, manufacturing, or a one-off build, the right selection helps ensure safe, consistent fastening and easier servicing over the life of the assembly.

Types of Hex Nuts

Standard Metric Hex Nuts

Standard metric nuts are the everyday choice for general fastening. They suit most common bolt sizes and sockets, and are typically specified by thread size and pitch (for example, M6 x 1.0). These are dependable for routine assemblies where standard strength, fit, and availability matter most.

Galvanised Hex Nuts

Galvanised options are coated, typically with zinc, to improve corrosion resistance. They are a popular choice for outdoor fixtures, structural brackets, and general construction where fasteners may be exposed to moisture. When comparing finishes for durability, galvanised nuts offer a practical balance of protection and cost.

Stainless Steel Hex Nuts

Stainless steel hex nuts are chosen for their higher corrosion resistance, especially in coastal, wet, or washdown environments. They are commonly used in food-adjacent areas, marine applications, and outdoor settings where rust prevention is critical and long service life is expected.

Nylon Hex Nuts

Nylon hex nuts (often nylon-insert lock nuts) help resist loosening due to vibration by providing friction at the thread engagement. They are used on moving assemblies, equipment panels, and light machinery where a standard nut might back off over time. These are a common solution when you want additional security without changing the whole fastening design.

Imperial Hex Nuts

Imperial hex nuts use inch-based thread standards rather than metric ones, similar to imperial hex keys. They retain relevance in imported machinery, legacy systems, and certain specialist industries. When working with older equipment or overseas specifications, confirming whether the threads are imperial or metric is a must before ordering.

Specialty / Variant Hex Nuts

Specialty variants extend performance or usability for specific needs. For example, flange hex nuts (also commonly referred to as flange nuts) include an integrated washer-like base that spreads load and helps protect surfaces. A flange nut can also reduce the need for separate washers and improve stability on softer materials. Other variants include dome-top (acorn) nuts that cover exposed threads for a cleaner finish and added protection, and bright zinc-plated hex nuts for general corrosion resistance and a neat appearance.

Features and Benefits of Hex Nuts

Material choice, thread design, and finishing all affect performance. When selecting threaded fastener nuts, these are the key features to consider:

Material: Steel is common for general strength, stainless steel improves corrosion resistance, and nylon-insert styles help with vibration. Selecting the correct material reduces failure risk and increases service life.
Thread Type & Size: Match the nut’s thread to the bolt’s diameter and pitch. Getting this right ensures proper load distribution and prevents cross-threading or loosening. This is especially important when buying thread nuts for mixed assemblies or maintenance kits.
Standard Compliance: Nuts manufactured to recognised standards provide consistent sizing and performance. This matters for repeatability in manufacturing and for critical maintenance work where fit and strength cannot be compromised.
Finish: Coatings like zinc plating or galvanising help slow corrosion, improving durability in damp or outdoor settings. The right finish also makes later disassembly easier.
Ease of Use: The six-sided profile is designed for fast tool engagement, making installation and removal straightforward, which is helpful for production work and routine servicing alike.

How to Choose the Right Hex Nut

Choosing the best option comes down to fit, environment, and practical handling:

Match to Bolt Size & Thread: Confirm the bolt diameter and thread pitch (metric or imperial) before purchasing. A perfect match improves clamping force and reduces the chance of loosening.
Select Material for Environment: For dry indoor environments, standard steel hex nuts are usually sufficient. For outdoor, coastal, or washdown areas where moisture and corrosion are more likely, choose stainless steel hex nuts or a corrosion-resistant coated option (such as zinc-plated or galvanised).
Choose Finish for Durability: Zinc-plated or galvanised finishes can be ideal for general corrosion protection. For long-term exposure, stainless steel may offer better resistance depending on conditions.
Consider Quantity & Packaging: Bulk packs help standardise stock and reduce downtime for ongoing maintenance. For prototyping or one-off jobs, smaller packs keep purchasing efficient.
Decide if You Need Added Locking or Load Spreading: For vibration-heavy assemblies, nylon-insert nuts can help. For protecting surfaces or simplifying your bill of materials, flange hex nuts can constitute an upgrade.

Applications of Hex Nuts

Hex nuts appear across countless assemblies because of their simplicity and versatility. Common applications include:

Machinery and equipment assembly: Frames, guards, mounts, and adjustable brackets.
Electrical and enclosure builds: Securing panels, rail mounts, and hardware inside cabinets.
Automotive and transport: General mechanical fastening, accessories, and fixtures.
Construction and infrastructure: Brackets, supports, and general site fastening where durability is required.
Maintenance and repair operations: Ideal for keeping standardised fastener stock on hand for quick replacements, especially where metric nuts are the default standard.

The Leading Supplier and Distributor of Hex Nuts in New Zealand

RS is a trusted supplier and distributor of hex nuts in New Zealand, offering dependable fastening solutions such as socket screws, washersand screw inserts for wood. RS New Zealand stocks quality products from leading brands, including RS PRO, Aerotight, and Guitel Hervieu, supporting consistent fit, performance, and availability for your builds. Whether you are ordering a small quantity for a specific job or standardising purchasing for ongoing work, we have options suited to common specifications as well as more specialised requirements.

Beyond nuts, RS also supplies a wide selection of related fastening and engineering essentials, making it easier to consolidate procurement for bolts, washers, tools, and maintenance spares through one online catalogue. Delivery options are designed to support real-world timelines, helping you get the components you need efficiently. For more information on shipping and service details, refer to our delivery information page.