Rivets

A rivet is a permanent mechanical fastener used to join two or more pieces of material—usually metal, but sometimes plastic or leather. Popular for numerous applications because they are easy to use and tend to be a set & forget proposition. Rivets work by clamping materials together using a metal pin that is deformed so it can’t come back out. Fundamentally a rivet is composed of two components, a metal tube (body) & pin (mandrel). The pin is normally longer than the tube and designed to be pulled up through the tube whilst enlarging it in the process. As the body expands and buckles it secures the material between the pin head and setting head. At a predetermined point, the pin used to pull up the body will break and drop off.

Key Rivet Points

• Rivets create strong permanent joints.
• Common in construction, aviation, metalworking, and structural steel.
• Often used when welding is impractical or when the materials can’t be heated.

Common rivet types

• Pop (blind) rivets — installed from one side using a rivet gun.
• Structural rivets — very strong; used in aircraft and vehicle manufacturing.
• Drive rivets jammed with a hammer.
• Semi-tubular rivets — easier to set; used in light manufacturing.
• Split rivets — for soft materials like leather.

Why rivets work well

• Don’t loosen with vibration (unlike bolts).
• Distribute the load well
• Work with thin or soft materials.
• Don’t require welding or heat.

Installing Rivets 

A rivet has a unique design that allows it to provide a secure and reliable fastening solution. Here's how they generally work:

1. Preparation: To install a rivet, you'll need a powered rivet gun or a manual rivet tool. The rivet consists of a cylindrical body (the shank) with a mandrel (a thin pin)  passing through its center of the body.

2. Insertion: The rivet's body is inserted into a pre-drilled hole in the materials to be joined. The rivet's shank should be long enough to pass through both materials with a small amount of extra length on the opposite side.

3. Pulling the Mandrel: With the rivet in place, the rivet gun is used to pull the mandrel through the center of the shank. As the mandrel is pulled, it deforms the unexpanded end of the shank, creating a "bulb" on the blind side of the materials.

4. Expansion and Locking: The bulb created by the mandrel's deformation expands against the backside of the materials. This expansion creates a secure grip and holds the materials together firmly. The mandrel eventually snaps off once the required pressure is achieved, leaving the installed rivet in place.

5. Finishing: The excess mandrel is discarded, and the installation is complete.

Rivets are often used in applications where a high-strength, vibration-resistant, and weatherproof joints are required. They are commonly used in the automotive industry, construction, HVAC systems, and more.