Rivet Buying Guide

Pop-rivets are a practical type of fastener designed for fast and easy attaching of thin-gauge materials, such as sheet metal and ducting. You’ll find them in HVAC installations, aluminum siding, trailer manufacture, home construction and woodworking projects. They don’t require a backing, base support or access to the back side of the materials being joined — unlike with a bolt and nut.

The definition of rivet is to fix in place or secure from moving. In the case of mechanical fasteners, this is accomplished by a short metal pin with a head on one end, which creates a bearing surface on the outside. The end without a head is passed through a hole, and this end is then pressed into place to create a second bearing surface on the inside.

So what are pop-rivets used for? Unlike traditional forged rivets — the kind you see on heavy iron work — that are passed through holes in the materials you are joining and are hammered from the back side to create a flat bearing surface, pop rivets are installed using a small tool called a pop-rivet gun. To pop rivet, you predrill holes through the thin-section materials you are joining. You load a rivet into your gun, insert the free end through the hole and actuate the gun. You can either use a manual gun with two handles you squeeze together or an automatic gun with an electric or pneumatic trigger.

When you actuate your pop-rivet gun, the central mandrel is pulled up while the head of your rivet is held against the outside surface. This action compresses and expands the bottom portion of the rivet until it reaches approximately 1.5 times its original diameter. The result is a larger bearing surface that holds your two materials together.

How to Choose the Right Rivet Size

You need to consider three different dimensions when choosing your rivets. Here’s how you measure a rivet:
•  Diameter of the rivet: This is typically expressed in 32nds of an inch — for example 4/32 inches
•  Maximum grip length: This is the maximum thickness of your materials, in 16ths of an inch
•  Mandrel or shaft diameter: This needs to correspond to your pop-rivet gun size

For example, a size 45 rivet has a 4/32-inch body diameter and a 5/16-inch grip length. A size 68 rivet has a 6/32-inch body diameter and an 8/16-inch grip length.

With this information, you can choose the rivets that are best suited to the sizes and types of material you’re riveting. Depending on the softness of the materials you’re joining and the number of rivets you want to install, you can choose a rivet with a larger or smaller diameter head. A large head offers increased bearing surface and will better resist pull-through and vibration. You can also look at the head height, which is a consideration if you want a smooth surface with a nearly flush rivet head.

Consult Our Rivet Size Charts

You can consult our rivet size chart to choose the rivets you need. In our All Points Fasteners online catalog, you’ll find three major families of rivets, each suitable for different applications:

•  Large flange pop rivets — with a large head for added strength and durability
•  Button head rivets — for a small and unobtrusive rivet head on your material surface
•  Painted button head rivets — if you require an attractive color and finish

Browse our catalog and select the rivet types and dimensions that suit your projects. We are happy to send you samples if you’d like to try our rivets before placing your order. Our helpful and knowledgeable team is available by phone or online if you have any questions or would like help choosing the right types of rivets for your application. We look forward to becoming your first choice for high-quality, American-made rivets and fasteners, so contact us today!

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