The back bodice is drafted using the same method as the front sloper, but this time anywhere on the standard measurement chart that has front and back measurements, use the back measurements (seems self evident, but not always obvious). So the back starts like the front, with the full length measurement, A to B. Draw a second line for the across the shoulder measurement (A to C) and square down from C approximately 3 inches. The Center Back length (B to D) is next, with 4 inches squared out from the top of the center back line. Then the back arc (B to E), with a square up from the end of the line.
Next is your back neck measurement (A to F) plus 1/8 inch. The shoulder slope (B to G) plus 1/8 inch. F to H is the shoulder length plus 1/2”. After drawing this line, square down from F to meet line D. B to I is the start of your dart, with B to J being the back waist arc, plus 1 1/2” for the Dart, plus 1/4” ease. The instructions for completing the second dart point was not crystal clear. I drew a point 1 1/2” from point I to mark point K. Point L is the center of the dart, halfway between points I and K.
J to M is a TINY little line, 3/16” long, marked down from point J. M to N is your side length measurement. O is your dart point and is drawn straight up from L. This measurement is 1” less than your Side Length measurement. Draw your dart legs and slightly round the lower edge of B to I, and K to M.
The upper dart got a little confusing, but I managed. First, cut your Shoulder Length (F to H) in half and mark this as point P. Q is 3” down from P, in a line with the top of the bottom dart at point O. P to R is 1/4” on either side of point P. Connect the legs of the darts from Q to R. D to S is 1/4 of the length of your center back length. Mark S, then draw a line S to T which is your across the back measurement plus 1/4”. Create a T square at the end of this line.
Finally, use your french curve to round out your neck and armholes. On the neck, make sure the curve touches at point F and the line at D. For the sleeve, the curve should touch at H, the line at T, and point N. And that’s it! Sloper back done! Remember, for this project, instructions are cribbed from Patternmaking for Fashion Design.