Sponsored: The Simple Circle Cutter, from Stockroom Supply, is specifically designed for plywood circles but will work on other materials, too. This is the only circle cutter with a built-in zero clearance, anti-chip out design. This jig properly supports the circle while cutting it, and has an adjustable height pivot point and non-static pivot point. Visit StockroomSupply.com to watch a video to see how easy this jig is to use.