one thing that I did not see mentioned in other replies.......I cut binding strips from selvage to selvage, only do bias binding when there is a scalloped edge.....that might be your problem.........and of course, must use the walking foot to apply. When trimming top before applying binding strip, I leave about 1/4" batting extended over the edge of the top.....this will fill that binding nicely when completed. Just what I found works for me. We all experiment a bit and find the best way for each of us.