I also don't iron when I spray baste. I have used Sulky spray, but now I just use half and half Elmer's Washable Glue and water with a couple of drops of dish washing liquid. I tried a fusible quilt batt on a wallhanging once and it left globs of glue on the surface in some spots. The diluted glue also leaves a few spots if larger drops get on it, but they wash out easily.