Finish Nuts

The Standard Fastener Nuts

Finish nuts are easily the most common type of fastener nut used. These nuts are often used with screws and bolts when mechanically joining materials together. They are installed on the opposite side of the materials being fastened. With the bolt head or machine screw head on the other side, they compress the materials together for a secure fit.

Finish nuts come in several varieties, most being some variation of the typical hexagonal shape. These varieties include the standard hex nuts, heavy hex nuts, machine screw nuts, structural nuts, and square nuts.

Hex Nuts

Hex nuts, or hex finish nuts, are the most common type of finish nut used. The hexagonal shape makes these nuts easy to grasp with a wrench or pliers.

Heavy Hex Nuts

Heavy hex nuts are similar to standard hex nuts but are physically larger, having thicker walls, for heavier loads.

Machine Screw Nuts

Machine screw nuts, sometimes just called machine nuts, are hex nuts under 1/4 inch in their internal threading. These kinds of nuts are used with small machine screws or bolts under 1/4 inch in thread diameter.

Structural Nuts

Sturctural nuts are heavy hex nuts made of a stronger grade of steel for structural applications, typically steel-to-steel structural connections. These kinds of nuts are typically made of plain steel, with no finish or coating.

Square Nuts

Square nuts, or square finish nuts, are the only finish nuts that are not hexagonal. The square, 4-sided shape of these nuts grants the nut greater surface contact with the material being fastened. This gives these nuts a greater resistance to loosening than standard hex nuts, but also greater resistance to tightening, making these nuts a little harder to install securely.

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FAQs

What is a finish nut?

Finish nuts are metallic blocks, usually hexagonal, with an internal thread designed to be used with a bolt or screw. They mainly help in creating a secure assembly alongside machine threaded fasteners.

What is the difference between a nut and a lock nut?

Standard fastener nuts are simply blocks of metal or other materials with a threaded hole in the middle. They are used to complete an assembly with bolts or screws but are vulnerable to loosening from vibration. Lock nuts, on the other hand, are designed to be resistant to loosening from vibration.

What is a hex nut used for?

Hex nuts are used alongside machine threaded fasteners to complete a secure assembly. The head of the screw or bolt clamps down on the material while the nut clamps down on the opposite side. This effectively "sandwiches" the assembly securely together.

How does a hex nut work?

Hex nuts work jointly with machine threaded fasteners such as bolts, anchors, and machine screws to effectively clamp down on both sides of the fastened material. The bolt and nut threading causes friction against each other, allowing a secure fit for general applications. A lock nut is used instead if the application would be subject to high amounts of vibration.