Every sewing project is unique, as are the materials and tools you need to complete it. When it comes to choosing the correct zip for a garment or bag, however, many amateur sewers are overwhelmed by the many options they have and to properly match those options with their project. Fortunately, understanding the two basic zip materials and three zip types and their applications makes deciding on the right zip for your project simple and fun.
Zip Materials: Metal or Plastic
There are two main types of materials used with the zip teeth: metal and plastic. Metal zips usually consist of aluminium, brass, and/or nickel. Plastic zips contain some synthetic material such as polyester, and less commonly, nylon. Metal zips are stronger and more durable than plastic zips, however they are also heavier. Therefore, most sewers prefer to use metal zips only with heavier fabrics such as denim and corduroy.
The All-Purpose or Coil Zip
The most common design for zips is the all-purpose zip, also called a coil zip or nylon coil zip. This is a lightweight zip with small teeth made of nylon or polyester. Because of these materials, coil zips are heatproof and rust resistant. All-purpose zips generally bend along with a garment or bag rather than hold a straight or flow with the item, making them an excellent choice for trousers, shirts, purses, and more. There is a lock at the end of each coil zip which prevents it from separating when undone. Available in a variety of colours, most sewers match coil zip with the garment in question in order to better conceal it.
The Invisible Zip
Technically theses are type of coil zip with a special teardrop-shaped pull. The invisible zip has very fine teeth and wide tape to conceal it within the garment. Properly attached, the only part of an invisible zip one can see is the zip pull at the top. Sewers commonly use invisible zips for skirts, dresses and frocks because of this feature.
The Separating or Open-Ended Zip
As the name indicates, once a separating zip is sewn onto a garment it allows each side of the zip to come apart from the other. Also called an open-ended zip, the box and pin mechanism at the base of a separating zip allows this action to take place. Although they come in a variety of sizes and types, most separating zips appear on coats and jackets. Deciding which material to use depends on the project. For example, a lighter weight garment, such as a fleece jacket, requires a polyester or plastic separating zip, where heavier fabrics are better off with a metal open-ended zip.