On 2 quilts where I used Bali pre-cut strips, I did not wash the fabric first, knowing that some of the batik colors would run. When I finished the tops, I machine basted wide, inexpensive muslin all around the quilt top edges and then washed (gently) with color catchers. After laundering, I removed the muslin; the seam allowances were intact and the muslin prevented unwanted threads from escaping into my washing machine.