When two seams to be joined are uneven in length, the longer edge must be drawn in to fit the shorter side. This is done, depending on the degree of adjustment, by easing or gathering, as shown.
Slight ease is the type that might be needed along the back side of a shoulder seam. Typically pin basting is sufficient (pins will hold the fabric layers together tighter than thread basting and will keep the fullness from slipping during the stitching process). To do the easing you will work from the longer side, pinning the seam at the ends and notches; then between the notches you will distribute the fullness evenly, pinning where necessary to hold it in place. Remove the pins as you stitch.
Moderate ease can be controlled by a dual process of machine basting, then pinning. Machine baste just the area of the longer piece that is to be eased in, then pin the seam at the ends of the basting and notches, as shown in the diagram on the previous page. Pin as needed to hold the fullness, then stitch the seam carefully, removing the pins as you stitch.
Gathering is the process of drawing fullness into a much smaller area by means of two rows of machine basting, such as you’d do with a gathered skirt. From the right side, stitch one basting line just next to the seam line; stitch the second ¼” away in the seam allowance. If seams intersect the gathered area, begin and end the gathering stitches at the seam lines. Pin the seam edges together at the matching points or notches. Draw up the bobbin threads, distributing the fullness evenly. Wind the drawn threads around a pin to secure the gathers, as indicated in the illustration on the previous page. Pin baste, then stitch the seam with the gathered side up; this prevents the gathers from becoming crooked and getting too much fabric sewn in with the gathered area.
These “how to” tutorials are an excerpt from our book “Basic Clothing Construction”. This book is a handy addition to have in your sewing room, so you can refer to the various sewing tips and tutorials at any time