To get the pattern piece of our new sleeve, we will modify piece #8 (sleeve head) by removing the 1 cm (3/8”) seam allowance at the bottom of the piece and adding a 2 cm (3/4”) hem allowance.
Start by tracing the sleeve head in your size, and place it on a new sheet of pattern paper. Tape in place.
On the left side of the piece, draw a line that extends the vertical edge of the seam allowance by 2 cm (3/4”). The total distance between the top end of this line and the bottom edge of the piece should thus be 3 cm (1 1/8”).
Draw an horizontal line starting at the top end of the previous line and meeting the left edge of the pattern piece. From the crossing point, draw a vertical line extending 4 cm (1 1/2”) down.
Now connect the end of the last line to the starting point of the first line. Here’s the side edge of your new hem allowance!
Follow the same steps on the right side of the pattern piece, and connect the two sides by an horizontal line which will be the new bottom edge of the piece. To sew this new version, simply follow the instructions for version A omitting piece #9, and finish the sleeves with a 2 cm (3/4”) single hem.