Some blocks I'm doing for these sets I am not satisfied with, as my middle triangles end up two different sizes after cut and then when sewn together in block points don't match. I measured 2" around sides, when I do the first cut it looks good, but when I go to do second cut triangle looks smaller than first cut. Any suggestions as to what I can try to get my middle triangles to match and be same size. My middle piece after all cuts measures 3".