Wet felting is a process used to make wool and other animal fibers into the dense fabric known as felt. The process involves the application of warm, soapy water, which causes layers of fleece placed at 90 degree angles to one another to hook together into a single piece of fabric. After the wet felting process is complete, the felted project is finished by fulling, or agitating the fibers on a rough surface such as a washboard. The felted fabric can then be dried and used to make accessories or garments.
Only certain types of fiber can be felted successfully. Most types of animal fleece, such as those taken from the alpaca or the Merino sheep, can be put through the wet felting process. This is because these types of fiber are covered in tiny scales, similar to the scales found on a strand of human hair. Wetting and soaping the fleece causes the scales to open, while agitating them causes them to latch onto each other, thus creating felt. Plant fibers and synthetic fibers will not felt, and neither will types of wool that are labeled as "superwash," as this type of woolen fiber has been chemically treated and lacks the outer coating of microscopic scales.
The wet felting process involves making layers of animal fleeces that have not yet been spun into yarn or thread. Usually, as few as two and as many as six thin layers of fleece are used, with each new layer being placed at a 90 degree angle to the layer below it. Most felted fabric is made using a single color of fleece, but two or more colors can be used as well to create interesting blends of color.
Often, wet felting is done by hand, using a screen to keep the layers of fleece together while soapy water is applied with a sponge. The process works best when the water used is hot and the soap used is a mild soap rather than a harsher detergent. Sponging the fibers creates slight agitation that encourages them to stick together. If too much water is used, the lightweight fibers will not stick together but will float away from each other instead.
The final step of the wet felting process is known as fulling. Fulling involves further agitation of the newly felted fabric. This process removes any air bubbles that might have been trapped between the fibers while felting, and makes the felted fabric stronger and tighter. Felt that has not been properly fulled can shed and fall apart over time. After fulling, the felted fabric may be rinsed with cool water to remove any remaining soap and then left to air dry.