How to Make & Stuff a Box Cushion
- 1). Cut high-density foam of any depth to your chosen length and width to make a cushion insert. Cut the foam with an electric carving knife. The length is the distance across the cushion, and the width runs from front to back. The depth is the thickness of the foam.
- 2). Cut two pieces of fabric 1 inch longer and 1 inch wider than the cushion insert. These pieces are the top and bottom of the cushion cover. If your fabric has a pattern, make sure the pattern is centered on the pieces before you cut.
- 3). Double the width and subtract 3 inches. Add the length to the result. Cut one strip of fabric to that total by 1 inch larger than the depth. Cut two strips of fabric 5 inches longer than the length by the depth. The strips will become the boxing band.
- 4). Multiply the length and width by two, and then add the totals together. Add another 3 inches. Cut two pieces of flanged welt cord to that length. Trim the flange to 1/2 inch, if it's wider.
- 5). Place the cushion top right side up. Pin the welt cord flange to the edges of the cushion fabric. Start at the back side of the cushion top, so the cord ends don't show on the finished cushion. Clip the flange at the corners, if needed, so the flange lies flat. Trim the excess welt once you've reached your starting point. Sew the welt to the cushion top with a 1/2-inch seam allowance. Repeat with the cushion bottom and the second strip of welt.
- 6). Fold one of the smaller fabric strips from Step 3 under lengthwise 1/4 inch, wrong sides together. Pin the folded fabric right side up along one side of a zipper, right next to the teeth. Stitch the fabric to the zipper, 1/8 inch from the folded fabric edge.
- 7). Fold the second fabric strip from Step 3 under 1 1/2 inches, wrong sides together inside the fold. Pin the folded fabric to the other side of the zipper, so the folded edge overlaps the teeth and the stitching from Step 6. Stitch the fabric to the zipper, 1/8 inch from the zipper's teeth.
- 8). Trim the width of the zippered fabric to 1 inch larger than the cushion depth. Trim parallel to the zipper on each side, keeping the zipper centered in the strip.
- 9). Pin one end of the zippered strip to the longer strip from Step 3, right sides together. Sew them together with a 1/2-inch seam allowance.
- 10
Place the cushion bottom right side up. Center the zippered part of the boxing band on the back side of the fabric. Pin the boxing band right side down around the perimeter of the cushion bottom. Clip the seam allowance at the corners, if necessary. When you reach your starting point, pin the loose ends of the boxing band together. Unpin just that part of the band from the cushion bottom. Sew the boxing band ends together, and then pin that portion of the band back onto the cushion bottom. Sew the boxing band to the cushion bottom with a 1/2-inch seam allowance. - 11
Unzip the zipper on the boxing band. Pin the other side of the boxing band to the cushion top, with the zippered portion of the band at the back. Clip the seam allowance when you pin the boxing band around the corners, if necessary. Sew the cushion top to the boxing band with a 1/2-inch seam allowance. - 12
Clip any loose threads, and then turn the cushion cover right side out. Roll the cushion insert up slightly on both sides, and insert it into the cushion cover through the zippered opening in the back. Unroll the sides of the cushion insert inside the cushion cover, and adjust the insert with your hands. Zip the cushion cover.
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