I soaked my Fiskars mat in vinegar water in the bathtub and brushed it but does not seem to be any better. I set it out on the deck to dry so maybe it dried too fast. My mat is probably a good ten yrs old. Guess I'm due for a new one. Dummy me didn't know how to take care of it. I love this website. I have learned so much and I love seeing the pictures.. Planning on making quilts for my two granddaughters who will be leaving for college in a year. Have pictures of them from babyhood up to today. Want to make picture quilts. Have to learn how first.