Phyllis asked me this week about how to convert an opening from a zipper to a button opening.
The conversion can easily be made following this procedure. First, find the center back line on the pattern. Next, you will need to add 1/2 inch to the pattern beyond the center back line. Draw a line parallel to the center back line at this measurement; this will be your new fold line. Now, measure 1 inch from this new line and draw a line parallel to the new fold line. This creates a facing for the overlap. This will be the line that you place on the selvage when cutting out the pattern piece.
When the fabric is pressed back on the fold line, a facing will be created that will allow for reinforcing the button holes. In a larger size that may require a larger button, you will increase these measurements from 1/2 inch to 5/8 inch to the fold line and 1 1/4 inch to the selvage line to allow for the wider button.
The same method can be used to convert a front opening shirt to a back opening or the reverse to a back opening.
I wish I had a white paper bag to draw a diagram. Many of you are used to my sending you home with directions on your sack!