Forming a seam is an easy thing to do. First one lines up the fabric and pins at regular intervals. Second, one bastes the seam either by hand or by machine using long stitches. Third, one stitches 5/8" into the seam line, backstitching at the beginning and end. Finally, one removes the basting, presses the seam together as it was sewn, and then presses the seam open. However, that seam isn't done yet. One still has to apply a seam finish.
A seam finish prevents an edge from fraying and makes it look neater as well. By doing this, a garment will last a great deal longer. Here are a few methods I learned during my sewing class. The pictures are the pieces of fabric I turned in for a grade.
This is the technique I use the most. It is quick, easy, and, quite frankly, pinking shears are fun! Stitch each side 1/4 inch from the edge and then pink. This method is especially useful on bias cut skirts. I do not recommend only pinking as it will not last as long and will probably fray. However, do not use this method when the seam edges can be seen through the fabric as the pinked edges would probably look a little strange.
Just like the name suggests, this uses the zigzag stitch on the machine. Use a medium width and short length stitch for this method. Sew close to the edge, without going over, and trim off the excess fabric close to the stitching. This method is very quick, but not appropriate for all situations. Test out this method on scraps first to get the right stitch lengths and widths and to prevent stretching, rippling, and curling. In addition, do NOT use this method on a bias. It will not be pretty. (I've learned from experience)
This method uses the over edge stitch on your sewing machine. Position the fabric such that the point of the stitch falls on the edge. As always, test it out on scraps first.
3-Thread Overlock Stitch
This stitch uses a serger, a completely awesome and scary tool. I don't have one, but I have a little experience using one in my sewing class. Basically, it is the same as the over edge or zigzag finish except using a serger. This method is what you see on garments bought from the store. It gives you a very professional looking finish while cutting off the extra fabric at the same time. This last part is what makes a serger frightening for me as a beginner. Once you sew, there is no redo as it has cut off your fabric. However, this is a good method for use on bias cut pieces. The stitch should just barely cut off the edge of the fabric.
|As you can see, I went a little crazy my first time and stitched much too close to the seam|
Should Seams Always Be Finished?
Yes, they should. One exception is if the garment is lined and the fabric does not have a tendency to fray excessively.
What if there is a curve or corner?
The same methods apply, but finish the edge first, then clip, and then press open.
There are many more ways to finish a seam, but these are the basics that should get a beginner through any project. Pick up the New Complete Guide to Sewing Reader's Digest for more techniques.