How do you “set-in” the squares and triangles on a lone star quilt without causing the fabric to pucker?

Dread30058: How do you “set-in” the squares and triangles on a lone star quilt without causing the fabric to pucker?
I am making the lone star quilt. Each time I set in the square or triangle, the middle piece of fabric has a pucker in it and it will not lie flat. I am also having trouble sewing the “y-seam” intersections. I am quite frustrated, can anyone help? Only serious quilters need reply.

Answers and Views:

Answer by Kacky
I used to do that too. Instead of quilt squares, I made bowls. The trick is to sew just to the right spot without going into your seam allowance at all. Here’s a good video that shows you how to make it come out right.

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