Originally Posted by Gabrielle's Mimi

With a 9mm throat plate what you want to do is purchase a single-hole throat plate (aka straight stitch throat plate), and switch them out for piecing. This is really important both for accuracy in seam allowances and to prevent fabric (especially points and corners) from getting caught down in the feed dogs. I also recommend either the #37 or #57 foot. They are the same but the 57 has a blade edge which allows you to butt the fabric to it and get a perfect 1/4" seam. The other thing I'd recommend is moving the needle 1 tick to the right or left to get an accurate seam. I find using a thinner thread like Superior's Bottom Line quite helpful, too, as it lessens bulk in the seam.