How many layers of fabric did you try cutting at one time? This will (if you do too many - ie: the max number they say you can - is too many), make some of your blocks out of shape. Also is the straight of grain going in the same direction on all layers? This too will make some of the blocks come out of shape (speaking from experience - lol). I just tossed the out of square blocks into the scrap bag, to be used to fill in on crazy quilts. Good luck