About felt and felting process
Felt is a non-woven cloth that is produced by matting, condensing and pressing woolen fibers. While some types of felt are very soft, some are tough enough to form construction materials. Felt can be of any color, and made into any shape or size.
Felt is made by a process called wet felting, where the natural wool fiber is stimulated by friction and lubricated by moisture (usually soapy water), and the fibers move at a 90 degree angle towards the friction source and then away again, in effect making little "tacking" stitches. Only 5% of the fibers are active at any one moment, but the process is continual, and so different 'sets' of fibers become activated and then deactivated in the continual process.
This "wet" process uses the inherent nature of wool and other animal hairs, because the hairs have scales on them which are directional. The hairs also have kinks in them, and this combination of scales (like the structure of a pine cone) is what reacts to the stimulation of friction and causes the phenomenon of felting. It tends to work well with woolen fibers, as their scales, when aggravated, bond together to form a cloth.
Cheaper felt is usually artificial. Artificial felt, if made using the wet method, has a minimum of 30% of wool fibers combined with other artificial fibers. This is the minimum required to hold a fabric together with the fibers alone. It would be difficult to achieve a stable fabric by hand at this ratio. All other wholly artificial felts are actually needle-felts.
An alternative way of creating felt is to have a steam roller go over the unwoven fabrics in a shallow pool of water with the cloth rotating as the steam roller goes over it. This method is widely used in small towns in India where mass manufacturing of clothing is done.
Nuno felting is a fabric felting technique developed by Polly Stirling, a fiber artist from New South Wales, Australia, around 1992. The name is derived from the Japanese word "nuno" meaning cloth. The technique bonds loose fiber, usually wool, into a sheer fabric such as silk gauze, creating a lightweight felt. The fibers can completely cover the background fabric, or they may be used as a decorative design that allows the backing fabric to show. Nuno felting often incorporates several layers of loose fibres combined to build up colour, texture, and/or design elements in the finished fabric.
The nuno felting process is particularly suitable for creating lightweight fabrics used to make clothing. The use of silk or other stable fabric in the felt creates fabric that will not stretch out of shape. Fabrics such as nylon, muslin, or other open weaves can be used as the felting background, resulting in a wide range of textural effects and colors.
Needle felting is a popular fiber arts craft conducted without the use of water. Special barbed felting needles that are used in industrial felting machines are used by the artist as a sculpting tool. Using a single needle or a small group of needles (2-5) in a hand-held tool, these needles are used to sculpt the wool fiber. The barbs catch the scales on the fiber and push them through the layers of wool, tangling them and binding them together, much like the wet felting process. Fine details can be achieved using this technique, and it is popular for 2D and 3D felted work.