4:1 pitch color coil binding is the most commonly used pattern for document and presentation binding. This coil binding has four holes per inch and is fully compatible with 6mm pitch coil binding (primarily used overseas). Four to one pitch color coil binding is available in sizes from 6mm to 50mm. This coil binding is the most commonly available color coil binding option and is designed for use with the majority of the smaller coil binding machines on the market. This coil binding is easy to work with binding books up to 1 inch thick, however, inserting 4:1 pitch coil binding on books greater than one inch can be difficult and time consuming.
5:1 pitch color coil binding is the second most commonly used pattern for document and presentation binding. This coil binding has five holes per inch and is also referred to as 5mm coil binding. The tighter spiral of this coil binding provides a distinctive look and is preferred by some individuals. One common misconception about 5:1 coil binding is that it provides a stronger more secure bind than 4:1 coil binding. This is simply NOT true. The fact that the 5:1 hole pattern places holes closer together than 4:1 makes it easier to tear the pages out on these documents. Still, the tighter coil binding of the 5:1 pattern provides a distinctive look that some individuals prefer when binding their documents.
3:1 pitch color coil binding is the third most commonly used pattern for document and presentation binding. With three holes per inch, this coil binding is compatible with both the GBC ProClick and the 3:1 wire binding hole patterns. It is primarily used by individuals who already have a 3:1 punch and wish to add the capability to bind coil documents. However, large auto punches and inline punches for photocopiers are sometimes sold with a 3:1 pitch die. While providing a look similar to its 4:1 counterpart, 3:1 coil binding is slightly easier to insert since it has less holes to spin the coil binding through.
The three pitches discussed above are the most commonly used pitches for coil binding. However, coil binding can be special ordered in several other unique pitches. For instance, .400 pitch coil binding is designed for a hole pattern that has 2.5 holes per inch. This coil binding is only available in diameters greater than 20mm or ¾” and is available in sizes up to 56mm or 2.25”. However, the filament size of this coil binding is larger than is normally found on other pitches of coil binding, making it more rigid making it easier to insert on larger diameter books. .400 coil is most often used along with a 2:1 pitch wire hole pattern. However, a few companies make specialty dies specifically designed for this pitch of coil binding.
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