The Different Parts of a Staple

The Different Parts of a Staple


A teacher decorating a bulletin board uses a different type of staple than a roofer attaching felt to plywood roof cladding. Staples come in varieties adapted to their appropriate use. Here is a guide to understanding the different types of staples.

Crown

The top part of the staple that shows on the surface of whatever you are fastening after you staple it is called the crown. The crown of a staple may be flat or rounded. Rounded versions are great for holding cabling in place along baseboards or within walls. The width of the crown can be as little as 3/16ths of an inch or as wide as 1 3/8ths inch for large, carton closing staples.

Legs

A staple’s legs are the two parts that extend downward on either side of the crown and penetrate the materials you’re stapling. Staplers apply staples manually (with that satisfying ca-chunk sound) or are powered by electricity or compressed air for heavy-duty jobs. Roofers or workers who apply house wrap often use a hammer stapler (also called a slap stapler or hammer tacker) that shoots a staple when you whack it against a surface, like a hammer.

In addition to choosing a staple by crown size, the length of the staple’s legs is an important measurement. The thickness of the material you are stapling will dictate the length of the leg you need. A general rule of thumb is that for thick materials, the leg should be three times the thickness of the material. The staple legs will crimp or splay outward when they enter the material. Fence staples, for example, have legs that diverge outward when applied to get a good grip on wood fence posts.

Light materials take staples with legs measured a few millimeters more than the maximum thickness of the material. The points on the end of the legs may be blunt and square or chisel-shaped.

Wire

The crown and legs of a staple are made from one continuous piece of wire, and the wire’s width is measured as a “gauge.” The wire itself is an important part of the staple. Counterintuitively, the higher the gauge, the thinner the wire. Thin wire staples are 22-20 gauge and thickness increased to heavy wire staples at 17-15 gauge. The wire may be rounded or flat. Aluminum, stainless steel, galvanized steel, and copper wire are all used to make different types of staples. Stainless and galvanized steel are better at resisting corrosion for outdoor applications.

If you’re not sure what kind of staple you need for your project, just ask. We at Staple Headquarters are happy to assist you.