When selecting a yarn for a certain project, it is critical that you understand the properties of the fibers. Do you desire a yarn that is both warm and insulating? The fiber is very soft, lightweight, and warm. Because the fibers are semi-hollow, they have a higher insulating value. Would you like a yarn that is only warm? The fiber is heavy weight, with a thicker strand structure. It is not as insulating as the first choice but would be useful if you need something warm to wear under other clothing.
Yarn is used to make fabrics, which are in turn used to make clothes. The three main ways to classify fabrics are by their appearance, by their feel, and by their use. Yarns can be classified by color, material, shape, size, etc. Depending on how the yarn is treated after it is spun from the fiber, it can be woven or knit into a fabric. There are two main types of fabrics: cotton and synthetic. Cotton is a natural product composed of long chains of glucose molecules connected together. This material is all around us and we rely on it every day for its comfort and durability. Synthetic materials are man-made products that are just beginning to replace cotton in some applications. They provide the benefits of warmth and insulation without the environmental impacts of cotton production.
Fabrics are used to make blankets, upholstery, and carpets.
Because of the air between the strands, iron fibers, such as steel wool, are good insulators. Iron is an excellent heat conductor by itself, however thin fibers alter this ability. The more strands there are per inch (25 mm), the better the insulation value. Steel wool comes in various grades from very coarse to very fine. The coarser the steel wool, the more likely it is to conduct heat. Fine steel wool can be used as a filter medium in heating appliances.
All metals conduct heat, but some metals tend to transfer heat faster than others. For example, copper is a good conductor of heat and electricity, while aluminum is not. This is because the metal atoms in copper are spread out far apart from one another, which allows many electrons to move through them at once. Aluminum on the other hand has an array of closely spaced atoms that allow only two electrons to pass at a time. These differences in conduction lead to different uses for these metals. Copper is ideal for use with high-temperature devices like stoves and hot plates because it doesn't melt like zinc or silver do. Instead, it just loses its electrical resistance and becomes a gas. On the other hand, aluminum is best used where weight is important such as when making lightweight structures like balloons and airplanes.
Yarns are long, continuous strands of spun-together fiber. Consider them to be small strings that wrap around one another to form a thick rope. The strength and thickness of yarns vary depending on how they are twisted. A high degree of twist results in a stronger yarn, whereas a low degree of twist results in a softer yarn. Yarn is used to make clothing, ropes, and other products.
String is simply a length of thin wire or plastic with holes through which you can tie knots. It is used to make musical instruments, such as guitars and pianos.
Yarn is usually made from wool or cotton, while string can be made from any material. However, when you need very strong string, you will often see it listed as "synthetic" or "industrial" string.
Synthetic string is actually just string woven from synthetic fibers. They can be made from polyester, nylon, or rubber and usually have a higher tension than natural string. This allows for a sharper sound when playing certain instruments such as violins.
Industrial string is string that is used in industrial applications where strength is important. It is usually made from steel or carbon fiber and has a much higher tensile strength than regular string. Industrial string is also less flexible than regular string, so it cannot be used to play instruments that require flexibility, such as guitar.