In order to begin to grade, it shall be understood that the model size pattern, which is the actual instrument for grading, shall be perfect in every way. It has been found that the most practical size for grading for regular women sizes shall be size 36.
Inasmuch as grading is only practiced for the purpose of making larger or smaller sizes from the model size, it shall be considered that such model pattern shall be first fitted out to perfection. For accurate grading it is advisable that the model pattern is made of heavy paper with a11 the necessary notches that such pattern may require for guidance in making up the garment. The grader is advised, before beginning, to study the necessary measurements for the next size or the various sizes of the pattern to be graded, for without this knowledge grading is very difficult.
It is very helpful to study how many parts the pattern consists of before beginning to grade. It is very important to study which parts of the pattern require most grading or which parts do not require any grading at all. This shall be carefully considered before any grading is started.
For best results in grading, work with a sharp pencil so that the pattern can be accurately copied and measurements can be accurately added from size to size. The tools that are required for grading are the pattern itself, a good sharp pencil and a very clear mind.
Before beginning to grade, prepare a model size pattern of a girdle. Note the difference between the model size and the next size that you wish to grade. If, for instance, the pattern you are grading from is size 30 inch waist measurement and you wish to grade to a size 31 inch waist measurement, the difference between the two sizes is only 1 inch. Therefore, there is actually ½ inch to be increased on all parts from size 30 to size 31. As the two piece girdle consists of front and back, each part representing half of the body, we shall begin to grade the front part first.
Now begin to grade as follows: Copy part 1, which is the front of the girdle. Copy from 1 to 2, illustrated by a dotted line, and move pattern in with ¼ inch from 1 to 3 and 2 to 4. Then copy balance of pattern from 3 to 5, 5 to 6 and 4 to 6. This will complete the increase of the front part of this girdle from size 30 to 31 waist measurement.
Now begin to grade the back part of the girdle. Copy, as illustrated with a dotted line, the center back part of the girdle from 7 to 8 and shift pattern in with ¼ inch from 7 to 9 and 8 to 10. Copy the balance of the pattern from 9 to 11, 11 to 12 and 12 to 10. This will complete the grading of the back part of the two piece girdle.
Bear in mind that we can grade from any size to any size desired. If, for instance, we wish to grade a girdle from a 30 to a 32 inch waist measurement, which means a 2 inch increase instead of 1 inch as described above, simply take half of difference between 30 and 32, which is 2 inches, and half of which is 1 inch. Equally divide this 1 inch by adding ½ inch to the front and ½ inch to the back of the garment instead of adding ¼ inch as for increase in a single size. It may be understood that we can decrease the pattern the same as increasing it. If a 29 inch waist measurement is desired instead of a 30 inch waist measurement, deduct ¼ inch instead of adding it at the center back and center front when grading to a size 31.