Wire binding is one of the most popular commercial book binding methods used in North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

 and is known by a number of different names including twin loop wire, Wire-o, double loop wire, double-o, ring wire and wirebind. With this binding method, users insert their punched pages onto a "C" shaped spine and then use a wire closer to squeeze the spine until it is round. Documents that are bound with wire binding will open completely flat on a desk, and allow for 360 degree rotation of bound pages.

Hole patterns and pitches

There are three common hole patterns used in binding documents with double loop wire. Each hole pattern has specific sizes and applications where it is best suited. Here is a quick overview of the different options.

3:1 pitch (3 holes per inch)

The three to one pitch hole pattern is most commonly used for binding small sized documents with double loop wire. Spines for this binding style are available in sizes between 3/16" (4.8mm) and 9/16" (14mm) in diameter. Three to one pitch wires are not available in sizes larger than 9/16". The size of the holes used with this pattern simply does not allow for larger spines to be manufactured. The hole pattern used for 3:1 pitch wire binding can use either square or round holes.

2:1 pitch (2 holes per inch)

Although a two to one pitch hole pattern is most commonly used for binding larger sized documents it can also be used for binding smaller diameter books. Two to one pitch wire is most commonly found in sizes ranging from 5/8" (15.9 mm) up to 1¹/₄" (32mm). However, a couple of manufacturers make special small sized 2:1 pitch wire for binding documents as small as 1/4" (6.4mm).

19 loop wire

In the past, some comb binding machines would come with a wire closer. These machines were designed to be used with 19 loop wire. Nineteen loop wire is designed to be used with a plastic comb binding pattern. This hole pattern will have longer rectangular holes that are 9/16" on center. This style of binding used to be referred to as Ibiwire which was Ibico's name for this style of binding. However, when Ibico was purchased by the General Binding Corporation

General Binding Corporation

General Binding Corporation is an office supplies manufacturer with many highly recognized global brands for binding, lamination, and other presentation products...

 this type of supplies was discontinued. Today, 19-loop wire is commonly called Spiral-O Wire.

Wire binding equipment

In order to bind documents with double loop wire a binding machine and a wire closer are required. Smaller organizations will often choose a small manual wire binding machine that offers a manual hole punch

Hole punch

A hole punch is a common office tool that is used to create holes in sheets of paper, often for the purpose of collecting the sheets in a binder or folder.The origins of the hole punch date back to Germany via Matthias Theel, where two early patents for a...

and a built in wire closer. Medium sized users will often choose a wire binding machine with an electric punch and built in wire closer. The highest volume wire binding users such as binderies, print shops and in-plant printers will usually separate the punching and finishing stages of the binding process in order to increase productivity. These users will often use a heavy duty modular interchangeable die punch or an automated punching system along with either a manual or an electric wire closing machine.