When I began CNC carving about 5 yrs. ago, I developed a fondness of Celtic Knots. There are hundreds of different kinds in many shapes (crosses, circles, square, rectangular, diamond). The left and center pictures are two of the first carvings I made with a CNC machine. The third picture is a shamrock shape for St. Patrick's Day. If you find a knot that captures your interest, send me a picture and I can carve it for you.