There are many types of seams you can use to join two pieces of fabric. Your choice depends on the fabric characteristics, the construction requirements, and the finished effect you would like to achieve.
Plain seam:This is the type of seam you’ll use the most often. With the right sides together, stitch 5/8″ (1.6cm) from the edge. Backstitch two or three stitches at the beginning and end of the seam. Press the seam flat and then press it open.
Narrow zig zag: This stitch prevents puckers by building stretch into the seam. It is effective with loose weaves and stretch fabrics. Set the machine for a narrow zigzag stitch and sew as you would a plain seam.
Flat-fell seam: This style of seam adds strength to the construction. With the wrong sides together, sew a 3/4″ (1.9cm) seam. Trim the lower seam allowance to 1/8″ (3mm). Press under 1/4″ (6mm) of the upper seam allowance, and pin it down, concealing the trimmed edge. Edgestitch on the fold.
Edgestitching: Stitch close to the seam line or edge to make a seam lie flat, as shown above. To create a sharp crease, stitch along a fold very close to the edge. Stitch from the bottom toward the top of a garment.
French seam: This type of seam is best for lightweight, sheer fabrics and visible seams. With the wrong sides together, sew a 1/4″ (6mm) seam. Trim the allowances to 1/8″ (3mm) and press to one side.
Fold the right sides together (enclosing the trimmed seam), with the stitching line on the fold. Stitch 1/4″ (6mm) from the folded edge. Press the seam to one side.
Seaming a straight edge and a curve Staystitch just inside the seam line of the straight edge. Clip into to the seam allowance up to, but to through, the stitching. Pin the pieces right sides together, with the clipped edge on top, matching any marks. Clips will spread so the edges match. Stitch, with the clipped edge on top, keeping the bottom layer flat. Press the seam open on a tailor’s ham.
Staystitch Stitch just inside the seam line of a single layer to prevent fabric from stretching out of shape. Curved seam lines – such as necklines, facings, armholes, waist-lines, and side seams over the hip area-require staystitching.
Tailor’s ham: Firmly packed, rounded cushion (half wool, half cotton) for pressing shaped and curved seams and sections.