Nuno Felting Q&A
I have been doing some nuno felting in August, had a few nuno felting workshops, and was going through the various notes I have compiled about nuno felting. Accordingly, I thought I would put down some of my nuno felting observations - in the form of a Q&A session. So if you want to know more about nuno felting, keep reading.
Q: So what exactly is nuno felting and how does it compare to regular wet-felting? A: Nuno felting is a specialized wet-felting technique that bonds loose wool fibers (or other animal fibers) through an open-weave base fabric—such as silk —using water, soap, and gentle agitation. Coined from nuno, the Japanese word for cloth, it creates a lightweight, draped fabric.
Q: How does nuno felting compare to wet felting? A: Key Differences
Materials: Regular wet felting uses loose wool fibers (or other animal fibers that will wet felt). Nuno felting combines loose wool/fiber with a sheer or loose-weave fabric, e.g. silk.
Thickness and Weight: Regular wet felting produces dense, thick, and stiff fabric; e.g. for bowls, mats, etc. Nuno felting yields thin, soft, and flexible material - e.g. for scarves.
Shrinkage: Regular wet felting shrinks significantly as wool fibers tightly interlock. Nuno felting shrinks less because the base fabric (e.g. the silk) restrains and stabilizes the overall dimensions.
Initial Technique: Regular wet felting begins with immediate gentle rubbing and rolling of stacked layers of fiber. Nuno felting requires initial careful pressing to force wool/fiber tips through the base fabric before agitation.
Q: When was the nuno felting technique developed, as compared to wet felting? A: The nuno felting technique was developed in 1994 by Australian fiber artist Polly Stirling - to create a lighter, more breathable fabric suitable for warmer climates. In contrast, traditional wet felting is an ancient craft dating back thousands of years to make such things as warm garments, tents, and boots.
Q: Can you nuno felt with just silk? Or can you also use other fabrics? A: You can use any open, sheer, or loose-weave fabric that allows fibers to migrate through and lock onto the material during the wet felting process - e.g. cotton will work. Here is the golden rule for nuno felting (the breath test): hold the fabric you are thinking of using up to your lips and blow through it; if you feel your breath easily on the other side, the weave is open enough for the fibers to pass through. But, wool (or a fiber that can felt) is required! Materials such as silk or cotton cannot bond to themselves; they must be combined with animal fibers (such as fine Merino) so the fiber can poke through the weave, tangle up, and trap the fabric.
Q: When nuno felting, the general advice, if using silk, is to use 3mm silk versus 8mm silk. What does this mean and what is the difference? A: The "mm" in silk fabric stands for momme, which is a traditional unit used to measure the weight and thickness of silk. One momme equals ~4.34 grams per square meter - meaning lower numbers translate to lighter, thinner fabric and higher numbers translate to heavier, denser fabric. So, 3mm silk is ultra-thin and sheer; 8mm silk is denser and opaque. Wool fibers easily pass through the loose weave of 3mm silk. 8mm silk has a tighter weave, making it harder for wool to pass through. (3mm silk has a highly irregular, loose weave with large microscopic gaps - often hundreds of microns wide. 8mm silk has a tight, plain weave, meaning the gaps between the threads are significantly smaller than in 3 mm silk.) All this means that 3mm silk felts with less effort than 8mm silk, which usually requires significantly more rolling and friction to bind. (Let me note that I have very successfully done nuno felting with 8 mm silk without any issues.) For the end result, 3mm silk results in a lightweight, fluid drape (and you can create a puckered texture) while 8mm silk creates a smoother surface and a stiffer, fabric.
Q: Some nuno felting tutorials say to start by using hot water and some say to start by using cool water. Which is it and what could be the effect of the water temperature? A: Depending on your fabric and wool/fiber, it could work OK if starting with hot water but it is highly recommended to start with cool or room-temperature water. Water temperature radically alters how quickly wool/ fibers react, and understanding its effect is the key to successfully bonding wool/fiber to fabric.
The Effect of Cool Water (The Initial Phase)
Slows Felting: Cool water keeps the microscopic scales of the wool/fiber closed and calm.
Allows Migration: It gives the individual wool/fiber time to physically migrate through the weave of your base fabric (like silk gauze).
Prevents Premature Clumping: If the wool/fiber felts to itself before it weaves into the base fabric, it will simply slide off instead of bonding.
Permits Corrections: The slower process gives you room to fix uneven layouts or shifting designs.
The Effect of Hot Water (The Fulling Phase)
Speeds up Felting: Hot water combined with soap allows the microscopic scales on the wool/fiber to open up wide.
Causes Immediate Interlocking: Once open, the fibers rapidly hook onto each other, tangle, and lock down.
Shrinks the Fabric: Hot water causes the fibers to crimp and shrink significantly.
The Ideal Strategy
Start Cool: Wet your layout with cool, soapy water to gently work and rub the fibers until they push through to the back of your fabric.
Finish Hot: Once you perform a "pinch test" and confirm the fibers have integrated into the fabric, switch to hot water for the fulling (rolling and tossing) stage to rapidly shrink and secure your final piece.
Q: Some guides suggest to lightly tack your fiber onto your fabric before wetting your fabric/fiber and starting the rolling process. Is this a good idea? A: Yes, this is an excellent and highly recommended idea for nuno felting. Why It Works
Prevents shifting: Loose wool/ fiber can slide out of position when water is first applied.
Secures design: Tacking keeps complex patterns, straight lines, or shapes exactly where you placed them.
Controlled wetting: You can apply water with confidence without blasting your fibers away.
PS In July 2025, I put a basic tutorial about nuno felting on the Withers Wool blog in which you can find a descriptive series of steps about nuno felting a scarf: https://www.witherswool.com/blog/2025/7/16/nuno-felting