A quilt based on the square and rectangles is the easiest to make but when you start to divide the square and rectangles there are endless possibilities.

There have been many unique and creative ways to sew these triangles for your quilt. The half-square triangle method I have listed below is not only fast and easy, but also accurate.  This method is based on creating strips of fabric, sewing them into a unit, cutting segments from the unit, and finally cutting the segments into squares.  Your quilt will have squares that are not distorted because the pressing is done prior to cutting the squares.

First, you need to cut the bias strips ½” wider than the finished short side of the triangle in the half- square unit from the fabric for your quilt.  The short side of the square will be any one of the 4 sides, not the diagonal of the triangle.   For units that finish 3” or larger, cut the strips, cut the strips ¼” wider than the finished short side of the triangle.

learn to sew tips, half square triangles

Follow these instructions to make the square for your next quilt:

  • Layer 2 contrasting fabrics with right sides facing up.  Align the 45∘angle of your ruler with the bottom edge of the lower left corner.  Cut long the right edge of the ruler.
  •  Cut bias strips in the width for the quilt that you are making.  Make the remaining cuts parallel to the first cut.
  • Cut the bias strips from the entire piece of quilt fabric.
  • Arrange the bias strips into 2 units.  Alternave the colors in each unit with the bottom left corner of each unit being a different color.
  • Sew the strips with right sides together using ¼” seam allowance.
  • Press the seam allowances toward the darker color.
  • Place the diagonal line of ruler on one of middle seams lines of the unit.  
  • Align a long cutting ruler, just covering the uneven ends of the strip unit. This trims the edge of one side of the squares.   
  • Retrim the edge of the unit before cutting each segment.
  • Cut the segment ½”  larger than the finished square.
  • Trim the edge of the unit again because the bias seams have a tendency to shift.  You must retrim the edge of the unit before cutting each segment.
  • Continue to cut segments until you have cut the entire segment.
  • To cut the squares, position the edge of the diagonal line on the seam line.  Cut on the right-hand side of the ruler.
  • Continue to cut squares across the segment, positioning the ruler on the diagonal line.
  • Turn the mat around and to place all the right hand cut on the left.    Place the ruler on edge of fabric with the diagonal lines on seam line, and trim he pieces into perfect squares for your quilt.

SEW wonderful to make perfect half-square triangles just ready for your quilt.

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