Wire binding is one of the most popular commercial book binding methods used 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, the punched pages go onto a "C" shaped spine and then a wire closer is used 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.
There are two 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 25mm) Up to 120 80gsm leaves – 240 pages
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 4.8mm and 14mm in diameter. Three to one pitch wires are not available in sizes larger than 14mm. 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) Up to 240 80gsm leaves – 480 pages
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 used in sizes ranging from 15.9 mm up to 32mm. However, we can use special small sized 2:1 pitch wire for binding documents as small as 6.4mm.