If you use the rag die you will be alarmed at the amount of strings being collected in the blade. You can spend a lot of time trying to pull them out or you can just let them alone. They will build up and be easy to pull out all at once. It won't hurt the blade or the dies. I have used my rag die this way for many rag quilts and never pull out the strings until they work themselves to the top in a bunch.