Lois, I'm wondering if you ever sew all of those layers at once, but I'd definitely use a jeans needle, a size 100 or more, go slow, and, use a bump jumper. I'm sure there's a better name, but I know it ships with Berninas...the white rectangular silicone thing to put under the back of the presser foot as you stitch over a thick part so that the presser foot stays level. If you are straight stitching, a straight stitch foot and throat plate will help support the needle, too.