Okay, when I cut, I measure very carefully. Usually my pieces are a few threads too big. So for the sake of my upcoming problem/question, let's assume I cut the pieces right.
I sew with a 1/4" foot. I'm careful to line it up and not push the fabric too far. I pin (and sew over the pins (IBC silk pins)). I start and end with the frog or whatever the scrap piece of fabric you sew over is called)
And yet, almost every block I sew, every pattern, biased, unbiased, squares, rectangles, triangles, just about every single one comes out about 1/8" shorter then it's supposed to. And after I sew a seam, before I press it open, sometimes I'll measure and it is 1/4" so I know I'm not secretly doing 1/2" or something.
I did a 10" BOM where almost every block was 9 7/8". And I know one of the comments is going to be "don't worry, at least they're all the same size" and I agree, I just can't figure out why the blocks keep becoming smaller... it has to be something I'm constantly doing since they all shrink uniformly......... help!