How to Process Fine Fleece into Nep-Free Yarn Neps are best described as dense, tangled clumps of the short fibers of the fleece. Some people don’t worry about neps and allow them to form to add texture to their yarn, but others prefer a nep-free, smooth yarn. There is no specific advantage to either, whether you like them or not is based off a personal preference. But, when attempting to make a perfectly smooth yarn, I often recommend three things: pick a sound fleece, make