What is a Pop Rivet and How Do They Work?

In workshops and assembly lines, you’ll often hear the sharp “pop” of a rivet gun setting fasteners—one after another. That’s the sound of pop rivets at work. As a simple and reliable fastening solution, they’ve been widely used for decades in industrial manufacturing, construction, and equipment maintenance.

Also called blind rivets, these two-piece fasteners are designed to join materials—like metal sheets, plastic panels, or composite parts—from one side only. You don’t need backside access or extra hands to hold a nut in place. That’s why they’re the first choice on production floors where efficiency and simplicity matter.

A pop rivet consists of two parts:

1. The Rivet Body: This is the hollow sleeve (or shell) with a flange (head) on one end.

2. The Mandrel: This is the solid stem that runs through the center of the rivet body. It has a thickened end (called the mandrel head) that sits inside the body and a long, narrow stem that extends out the back.

Pop rivets come in various materials like aluminum, steel, and stainless steel, so you can choose one that matches the strength and corrosion resistance you need.

How Does a Pop Rivet Work?

The magic of a pop rivet is in its simple yet effective installation process. You’ll need a special tool called a pop rivet gun or riveter. Here’s how it works, step by step:

1. Drill a Hole: First, a hole is drilled through the materials you want to join. The hole’s diameter should match the size of the rivet you’re using.

2. Insert the Rivet: The rivet is placed into the nose of the rivet gun. Then, the rivet’s body is inserted into the pre-drilled hole. The flange (head) will rest against the outer surface of the material.

3. Squeeze the Handle: When you squeeze the handle of the rivet gun, it pulls the mandrel stem backward. This action causes the mandrel head to press against the inner walls of the hollow rivet body.

4. Deform and “Pop”: As the gun keeps pulling, the force causes the rivet body to expand and deform on the blind side (the side you can’t see). This creates a second “head” that clamps the materials tightly together between the original flange and the new head.

5. Break the Mandrel: Once the joint is secure, the tension becomes too much for the weakened section of the mandrel. It snaps—or “pops”—with a satisfying sound, leaving the deformed rivet body permanently in place. The leftover piece of the mandrel is ejected from the tool.

And that’s it! You’re left with a strong, permanent fastening.