Seams are the lines of stitching which hold two pieces of fabric together. In general, we try sewing seams as inconspicuous as possible, and in most cases, as strong as possible. For this reason always make sure that you use good quality cotton for sewing seams.
The types of seam we use depend on the strength and the appearance we want to give. In some cases the seam may be used as part of the decoration, or for a functional purpose.
- Plain seams are simplest and are used most often. Put two pieces of material, right sides together, and stitch on wrong side at required seam allowance, usually ½ inch (1 cm) from edge. Open and press flat. Edges may be pinked.
- Stitched plain seam is made in the same way as a plain seam and then stitched again on the right side 1/8 inch from seam line on one or both sides for a tailored effect.
- Flat fell seam is used when you need a flat finish, as in shirts and pyjamas. Make a plain seam, trim one edge to 1/8 inch, and turn in other edge ¼ inch (1/2 cm). Baste to position over trimmed edge and edge stitch. This is usually done on the right side.
- Hem felled seam is made like flat fell except that seam is hemmed, rather than edge stitched, for a softer effect.
- Flannel fell seam is used on heavier fabric, like wool. Make a plain seam, trim one edge to ½ inch (1 cm), and fold other part over without turning in raw edge. Catch stitch.
- Welt seam is used for flat finish on heavy material. Make a plain seam on wrong side, trim one edge, fold the other over it without turning in the raw edge, and stitch on outside. For double welt, stitch a second line close to original seam stitching.
- Slot seam is a decorative seam, sometimes to show another colour or design underneath. Turn both seam edges under on sewing line, lap them over a strip of material, with edges meeting or not as desired, and stitch the proper distance from the fold on both sides.
- French seam is used for sheer materials and underwear. Make a plain seam on right side (with wrong sides together), ¼ inch outside the seam allowance. Trim edges to ½ inch, turn to wrong side and stitch on seam allowance to make this seam within a seam. Do not allow any frayed edge to show.
- Upholsterer’s seam is made like a French seam except that you start on the wrong side and the finished seam shows on the right side. The effect is like that of cording and is often used for slip covers.
- False French seam is made with a plain seam on wrong side. Turn edges under ¼ inch and sew together with running stitch or by machine.
- French fell is made with a plain seam and one thickness is then trimmed to ½ inch. Fold other edge over cut edge, turn in ¼ inch, and hem to machine stitching.
- Fagoted seam has a space between fabric edges. Decide how far apart edges are to be, turn edges back one-half the width of the finished open space, baste them to a slip of paper, and fagot. Very decorative.
- Hemstitched seam is basted as for plain seam, and pressed to one side. Have seam hemstitched and trim seam allowance close to hemstitching. A line of machine stitching can be done ½ inch (1 cm) from stitching on wrong sided.
- Lapped seam will look like a fell seam when finished. Turn one piece of material under on the seam allowance. Baste the folded edge on to the right side of the other piece, at the seam allowance. Edge stitch.
- Tucked seam is similar to lapped seam except that the final stitching is done not at the edge, but at a distance from the fold. The effect is like that of a tuck.
- Lapped hemstitched seam is done by lapping seams, as explained under lapped seam. Hemstitch over the basting, trim away seam on wrong side.
- Machine picoted seam is like hemstitched over the basting, trim away seam on wrong side.
- Rolled whipped seam . Make a plain seam, trim the allowance to half, roll edges tightly a little at a time, putting needle under roll, not through it.
A lot more about sewing seams and seam finishing techniques in Sewing Seams 2.