If you washed them in the sink like you were planning and then put them on your drying racks they probably will be ok. You might try one or two strips of different fabric (incase you decide to send the jelly rolls back) and see how they handle but I bet you will be fine. When they tumble in the dryer that is the biggest problem. They tend to shred all up especially since both raw edges are so close to each other. Good Luck. Jelly rolls are a lot of fun. Hopefully you can get them dust free so you can play.