 | Creative Grids 22-1/2 Degree Triangle Ruler. Sew together 16 of these 22-1/2 degree triangles to create a complete circle; 8 to create a half-circle; or 4 to create a quarter-circle. Create Fans, Dresden Plates, etc. up to a finished size of 18 inches.... - Creative Grids 22-1/2 Degree Triangle Ruler. |