Unlike textiles such as silk, viscose, linen and cotton, which are made by spinning fibers into threads and weaving them into fabric, felt is made by matting, condensing and compressing the fibers together. Felt can be made of both natural and synthetic fibers.
Legend has it that the felt was accidentally created when Saint Clement, patron saint of Hatters, and Saint Christopher, patron saint of travelers, fleeing persecution by the Romans, wrapped their legs in wool to avoid blisters. Another popular legend says that a Persian shepherd, who believed that it was possible to make waterproof mats from sheep's wool without the help of a loom, unsuccessfully glued the fibers. Crying, he stepped on the fur, and at that point, they finally connected. Another myth says that the animals in Noah's ark lost their hair on their journey and trampled it under their feet, after which Noah found that the floor of his ark was covered with felt. However, while each of these stories deals with the steps involved in making felt - wool, moisture, and shrinkage - none of these stories are true, as there is archaeological evidence to prove the existence of of felt before Christianity was widespread.
A common process of making felt is called wet felting, in which the natural wool fibers, friction incentives and lubricated with soapy water, are moved at a 90-degree angle to the source of friction, and then removed again in effect making little "tacking" stitches. Although only 5% of the fibers are active at any given time, the process is continuous so that different groups of fibers are activated and then deactivated eventually building up the cloth.
In the early 20th century, popular men's hats, such as felt hats and homburgs, were typically made from felt. In the wet felting process, hot water is applied to layers of animal hairs, while repeated agitation and compression causes the fibers to hook together or weave together into a single piece of fabric. Wrapping properly laid fibers with durable textured material such as bamboo mat or burlap will speed up the felting process. The felted material may be finished by fulling.
Only certain types of fibers can be successfully water-felt. Most types of fleece, such as those from alpaca or merino sheep, can be subjected to the wet felting process. You can also use mohair (goat), angora (rabbit) or hair from rodents such as beavers and muskrats. These types of fibers are covered with tiny scales, similar to the scales found on a human hair. The heat, movement and humidity of the fleece causes the scales to open, while their agitation causes them to cling to each other, creating felt.