Creative Grids 4in Curvy Log Cabin Trim Tool Create the illusion of curves with this 4" version of our popular Curvy Log Cabin Trim Tool. Sew four blocks together to, piece a circle which finishes to 8". Combine these blocks with other 4" blocks for unlimited design possibilities. The tool features easy-to-read black and white markings and the popular Creative Grids® grip. The ruler slides easily over the fabric until pressure is applied; then, our exclusive gripper holds the fabric in place while cutting, eliminating slipping and miss-cuts!