I have three Martelli mats, first one damaged in shipping, replacement had lines that were 1/4 inch off (discovered after I cut out fabric for a quilt). The third is ok. I love the table but the rulers and templates leave a lot to be desired. I am hoping that they will be at our quilt show so they can explain to me what I am doing wrong. I would send a picture of your mat to them and complain. They should send you a replacement.