Fastener Selection: What Barrel Length Do I Need for My Snap?

Item # X-HT-300033

Picking out all the proper snap fastener components for your canvas projects can be daunting if you don’t know what to look for or where to start. That’s where we come in! In this post we’re going to focus on selecting the right barrel length on your snap fasteners for the thickness of your fabric. If you need help selecting which type of fastener to use, head over to our Choosing the Right Fastener Type article (300029XHT).

The top three most popular barrel lengths for buttons

The barrel is the part of the fastener that gets riveted to the piece’s mating component. In other words, it’s the straight stem-like part that comes out of the button top. If your barrel is too short, it won’t be able to rivet through all of your fabric layers but if the barrel is too long, it will get in the way of your snap functioning.

11/64” and 3/16” is the most common barrel size for buttons. Here’s a helpful chart for quick reference that breaks down which button barrel length is best for the layers of canvas in your project. The numbers for “layers of canvas” are based off of layers of Sunbrella Marine Grade material.

Layers of Canvas Barrel Length
2 - 6 11/64" & 3/16"
6 - 9 1/4"
9 - 12 5/16"

The eyelet part of a snap fastener also has a barrel, but it’s sizing is a little different. Since the eyelet rivets to a larger piece of hardware, the stud, the 1/4” barrel for eyelets is standard for most projects. However if you’re assembly is very thick, over 7 or 8 layers, then you’ll want to move up to the 5/16” barrel.

To learn more about fasteners, check out the More Helpful How-Tos in the right-hand column.