Know Your Nuts: Shaped NutsPhoto by Edge2Edge Media

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Next up in our educational series called Know Your Nuts, we’re talking about different types of shaped nuts. The use of shaped nuts varies from type to type, but in general, they all share some aspect of their design with more common standard nuts, with an extra feature added to achieve a specific functionality. Below are four of the shaped nuts most commonly used in construction and industrial applications.


Cap Nuts

Cap nuts are traditional hex nuts with the addition of a smooth dome on one side. These are used in assemblies where protection of the bolt or threaded is important after assembly, either for performance or for safety. Cap nuts can also be used for purely aesthetic reasons, such as in automotive uses or in residential construction, where the end of a bolt could cause an unsightly distraction for the user.


Acorn Nuts

Acorn nuts are a type of cap nut, where the domed side is pointed with a higher crown. This creates greater internal depth, allowing the bolt or rod to be threaded further into the nut.


Square Nuts

As opposed to the traditional hex (hexagonal) nut with its six sides, square nuts only have four sides and look exactly as they sound, a perfect square. Square nuts are typically used where there is an inset or channel in the receiving surface, such as in furniture, railroad applications, or other metal assemblies. The larger surface area of square nuts allows them to more easily resist loosening.


Wing Nuts

Wing nuts feature a head with two “wings” across from each other, making the nut able to be tightened and loosened by hand. Sometimes referred to as a “butterfly nut”, these are mostly used for the purpose of temporary fastening, but can also be found in bicycles and musical instruments.

If you have further questions about shaped nuts, please don’t hesitate to contact us for more information.