Hi All--I've been following the recent threads about creating string strips using receipt paper. I think it's such a cool idea. I'm ready to start sewing a few mixed scraps onto the receipts, but wondered if they should be washed first, considering that they are all such different fabrics and will probably shrink at different rates once in a string quilt. I don't usually prewash my fabrics, but in this case it seems like it might be in order. I'd appreciate your advice.