Quilt binding is often made of solid-colored fabric to create a visually contrasting edge that frames the quilt pattern. However, your corner finishing technique is much more visible on solid-colored fabrics. As a result, you may find that corner finishing techniques that simply overlap border strips produce a look that is not pleasing to the eye. With only a little extra time and work, you can create professional-looking mitered corners, leaving your finished quilt much more tailored.
Cutting Quilt Borders for Mitering
Measure the width and length of your quilt at the center and record these measurements.
Calculate the length of your quilt border strips. Multiply the width of your border by four and add 1/2 inch for seam allowances. For example, 2-inch width times 4 = 8 inches + 0.5 inch = 8.5 inches. For a 36-inch by 48-inch quilt with 2-inch-wide border strips, you need widthwise border strips that are 2 inches by 44.5 inches and lengthwise border strips that are 2 inches by 56.5 inches.
Cut two widthwise border strips and two lengthwise border strips. Piece together several strips of fabric, if necessary.
Attaching Quilt Borders for Mitering
Pin the border strips to the raw edges of your quilt, right sides together. The strips should extend an equal distance past the quilt edge on each side.
Stitch the border strips to the raw edges of your quilt using a 1/4-inch seam allowance. Begin and end stitching 1/4 inch from the edges of the quilt at the corners and be sure to backstitch to secure your seam. Pin the adjacent border strip out of your way when you near the corner, so that you don't accidentally stitch onto that border strip.
Press the seams open or press the seam allowances toward the back of the quilt.
Mitering Quilt Borders
Lay the quilt face-up on your ironing surface. Begin at one corner and fold both border strips back on themselves at a 45-degree angle—the strips should meet at the angle. Press the border strips to create a crease to use as a guideline later. Unfold the creased border strips.
Fold the quilt on the diagonal, right sides together. Match the border strips together along the ironed crease and pin them together.
Place a ruler along the folded edge of the quilt. The ruler along the folded edge should line up with the crease in the border strip. Mark the crease with a pencil.
Stitch the two border strips together along the marked line, starting from the precise point where you left off stitching the border to the quilt (i.e., 1/4 inch from the quilt edge). Backstitch at each end to secure your seam.
Unfold the quilt and check your seam for gaps, puckers or pleats. If there are faults in the seam, rip it apart with a seam ripper and try again.
Press open the seam on your mitered corner. Flip the quilt over and press the right side of the seam, as well.
Sew several strips of fabric together lengthwise to create a double or triple border—and be sure to line up all of the seams precisely when mitering the quilt corner.
Check your work before trimming your seam allowances, or it will be difficult to repair pleats.