I hope someone can answer this question....I have to piece together my batting to make it big enough for my quilt. I am using the fusi-boo fusible batting.... (this is the batting that eliminates the need for basting) my question is after I sew the two pieces together can I use my iron to iron the seam flat or will it ruin the fusibility of the batting (on that seam) when I try to fuse it to my quilt/backing? Hope I explained this well enough.....I think I have to iron out the seam so it's not raised inside the quilt....