I purchased a large piece (18x22) of acrylic at Menards and an acrylic cutter for $1.99 because I needed an 18 in square and didn't want to spend so much on a ruler I didn't think I would use very often. My plan worked - almost. While cutting the acrylic, the one corner broke off. So I just took another ruler and laid it on top of the broken corner while cutting my blocks.