What Are the Different Types of Bolts That Exist Today?

Screw threads date all the way back to 7th century BCE, and while bolts have come a long way since then, that basic threading still exists today. 

While bolts and screws have been around for a long time, they have evolved, and now, there are plenty of bolt varieties for different types of applications. Are you trying to figure out which types of bolts you need to add to your toolbox?

Perhaps you’re getting into woodworking or renovations, and you need to make sure you’re choosing the right types of bolts for the projects you’re taking on.

Below, we are going to talk about some of the types of bolts out there and tell you what they are commonly used for. Keep reading to learn more! 

Carriage Bolts

A carriage bolt is a fully-threaded bolt that has a smooth head and a ribbed or square undercut. This prevents the bolt from turning as it is tightened. 

Carriage bolts are traditionally used to fasten metal onto wood. 

Eye Bolts

This is a rod-shaped bolt fastener that has threads on one end. The other end is bent into a loop shape. 

Eye bolts are usually used when a person wants to lift something, like wiring or rope lighting.

Anchor Bolts

An anchor bolt is threaded on one end with the other end shaped like an L. These are often used with a washer and a nut to stay secure. 

Anchor bolts are designed to be rust-resistant, making them perfect for securing structural beams, fastening items to concrete, or securing light posts. 

Elevator Bolts

This is a fastener that has a thin flat head and a square undercut, which prevents the bolt from turning when it is tightened. The shape and design of this bolt are different than the carriage bolt, but they still both feature that undercut in the square shape.

As you may have guessed, elevator bolts are used for conveyor systems and elevators. 

Hanger Bolts

Hanger bolts are unique because they don’t come with a head. Both of the ends on hanger bolts are threaded, and one of them is shaped like a wood screw. 

These are used for fastening metal to wood in aloft applications. 

Machine Bolts

These are square head bolts that have a completely threaded shaft. They are widely used to fasten wood to metal, wood to wood, or metal to metal. You’ll often find these as a general bolt option for many projects that don’t require a specialized type of bolt. 

Hex Bolts

The head of a hex bolt has six sides, and the bolt is completely (or at least partially) threaded. 

Hex bolts have a lot of different uses from construction to highway repair. They are extremely strong, so they have a lot of application purposes related to infrastructure. 

J Bolts

As the name suggests, these bolts are shaped like a J, and the non-curved part of the bolt is threaded. 

J bolts are usually used for constructional applications, like when a wall needs to be fastened to a slab of concrete.

Explore the Many Types of Bolts for Your Projects

These aren’t all of the types of bolts that exist, but they are some of the more basic ones to get you started. If you have a specific project in mind, be sure to research the specific tools you’ll need to make sure that the construction or renovation is safe. 

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