For a size 6 inch (9 inch, 12 inch) quilt block using 3 different fabrics Cut Fabric A – Center Square 1 square -‐ 2 ½ inches (3 ½ inches, 4 ½ inches) Fabric B – Main Accent Fabric 4 squares -‐ 2 ½ inches (3 ½ inches, 4 ½ inches) 2 squares – 3 ½ inches (4 ½ inches, 5 ½ inches) Fabric C Secondary Accent Fabric 2 squares – 3 ½ inches (4 ½ inches, 5 ½ inches) Start with sewing 4 half square triangles. Take the 2 Fabric B and 2 Fabric C 3 ½ inch squares. Line them up so that the printed sides are together touching (right sides together) and make a mark from one corner to the other diagonally across the square.
Then draw a line on ¼ inch on either side of the diagonal.
Sew a seam along the 2 outer lines.
Cut along the centerline, taking care to leave ¼ inch seam allowance on the 2 resulting blocks.
Open the half square triangles and press toward the darker fabric
Because we made the blocks larger than we need, now we trim the half square triangle to match the other squares we have for this quilt block. Lay the square ruler diagonal along the half square triangle seam, making a square slightly larger than 2 ½ inches (3 ½ inches, 4 ½ inches).
With a rotary cutter, cut along the ruler edge.
Flip the square around and line up the freshly cut edges of the square along the 2 ½ inch (3 ½ inches, 4 ½ inches) lines of the ruler.
Cut along the ruler edges.
Lay out the 9 squares, placing the center square in the middle and the half square triangles at the corners with Fabric B pointing outward.
Then place the remaining Fabric B square at the top, bottom and sides.
Sew each of the three squares of each row together pressing the seams for the center row outward.
Press the seams for the top and bottom row inward.
Lin up the top and middle rows, taking care that the Fabric C point is touching the center square. Line up the seams and sew the rows together. Repeat for the bottom row. Here is the Shoofly Quilt Block