Felt is a non-woven textile that is produced by matting, condensing and pressing fibres together. Felt can be made of natural fibres such as wool or synthetic fibres such as acrylic. There are many different types of felts for industrial, technical, designer and craft applications. While some types of felt are very soft, some are tough enough to form construction materials. Felt can vary in terms of fiber content, colour, size, thickness, density and more factors depending on the use of the felt.
Felt is made by a process called wet felting where the natural wool fibres, stimulated by friction and lubricated by moisture (usually soapy water), move at a 90 degree angle towards the friction source and then away again, in effect making little "tacking" stitches. While at any given moment only 5% of the fibres are active, the process is continual, so different 'sets' of fibres become activated and then deactivated, thereby building up the cloth. This "wet" process takes advantage of the inherent nature of wool and other animal hairs. The hairs are made up of unidirectional scales, and they are also naturally kinked. It is this combination which reacts to the friction of the felting process, forcing the scales on the hairs to lock together and thus causing the phenomenon of felting. It tends to work well with wool fibres because their scales, when aggravated, readily bond together..
Needle felting is a popular fibre arts craft that creates felt without the use of water. Special needles that are used in industrial felting machines are used by the artist as a sculpting tool. While erroneously referred to as "barbed" needles, they in fact have notches along the shaft of the needle that grab the top layer of fibres and tangle them with the inner layers of fibres as the needle enters the wool. Since these notches face down towards the tip of the needle, they do not pull the fibres out as the needle exits the wool. Once tangled and compressed using the needle, the felt can be strong and used for creating jewelry or sculpture. Using a single needle or a small group of needles (2-5) in a hand-held tool, fine details can be achieved using this technique, and it is popular for 2D and 3D felted work
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 fibre, usually wool, into a sheer fabric such as silk gauze, creating a lightweight felt. The fibres 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 colours. It can be made in many weights to accommodate many different uses. It can be made much lighter in weight than traditional all-wool felt accounting for its wonderful movement and drape. Because of the range of weights possible with the cloth very fashionable and exciting garments can be made.You would make a very light weight nuno fabric by laying one layer of loose fiber onto an open weave fabric base, thus being suitable for a summer dress. A much heavier nuno fabric results from laying 3-4 layers of loose fibers onto an open weave base making fabric suitable for a winter coat. A pair of boots could be made using even more layers of fibers.Wool is only one kind of ﬁber that can be used in making this nonwoven cloth. There are hundreds of different wools and ﬁbers to choose from, each with its own unique properties and handling abilities. Different ﬁbers create different surface textures. Other types of ﬁber that will felt other than sheep's wool are: camel, llama, alpaca, Mohair goat, Cashmere goat, yak, Angora rabbit, beaver, dog, cat, human hair (think dredlocks).