Deluxe Corner Trimmer & Hand Piecing Aid from Marti Michell Trim away the “dog ears” on 4 acute angles on any size piece before sewing. Eliminate bulk and improve accuracy. Mark the dot where 2 seams cross, as needed, for hand or machine piecing. Sew. You’ll love how pieces fit together perfectly-by hand or machine. Tumbling Blocks, pieced with “dog ears” and without!