Pattern Grading Basics (1)

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Pattern-Grading

Basics

How to scale from the size you have to the size you need By Co n n i e C raw f o r d

P

attern grading can seem mysterious to home sewers, but it needn’t be. Grading is the proportionate increase or decrease of a pattern from one size to the next. You can grade patterns up (make them larger) or grade them down (make them smaller). Whether you wish to grade a single-size or a multisize pattern, you need to understand the principles by which patterns are graded, as well as the method of hand grading. Knowing how to grade patterns by hand is an essential skill for any patternmaker, whether professional or home sewer. Even professional pattern graders learn this hand-grading technique before they move on to grading by computer. It isn’t simply a matter of expanding a pattern at its side seams until its circumference matches the needed measurements. The increase or decrease must be distributed throughout the pattern to maintain accurate proportions. Once you’ve grasped the basics, you’ll be able to resize any pattern by as many sizes as you wish; you can grade consecutive sizes individually ( from an 8 to a 10 to a 12) or grade by multiples ( from an 8 to a 14 in one step). Note that grading only changes a pattern’s size—it does not alter the fit to an individual figure. Just as you would for any other untried pattern, you should sew a muslin of a pattern you’ve graded to a new size to check for necessary fit alterations.

Gr ad i n g to o ls

In the industry, hand grading is done using a grading machine

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or a grading ruler. A grading ruler is a thin, clear plastic, gridded template with 1/8-inch increments marked, as well as X and Y axes and grainline directional markings. These tools guide you in shifting the pattern in four directions at specific intervals along X and Y axes, according to the pattern’s “grade” (explained on page 44). At each interval, a section of the pattern is traced, yielding a larger or smaller size than the original. A grading ruler (available at FashionPatterns.com) is an inexpensive tool, and easy to learn to use. C h o os e a l ear n i ng pat ter n

You can grade patterns for any garment style and type, but it’s easiest to learn hand grading using a basic bodice pattern. Grading a pant or a skirt is different from grading a bodice. Although the circumference of a pant or skirt pattern increases between the sizes the same amount as for a bodice, the growth increments are distributed differently. To learn the hand-grading method in this article, choose any basic bodice pattern with darts; it may have waist darts or bust darts, or both. Start with any size pattern you wish; you can grade it to any size needed. Author and educator Connie Crawford designs sewing patterns and teaches around the country. Her Grading Workbook, Second Edition (Amaden-Crawford LLC, 2013), is available at FashionPatterns.com.



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Understand the grade To grade a pattern, you need to know how much you want its circumference and length to increase or decrease, and how to distribute the growth increments throughout the pattern piece.

The circumference grade The amount of circumference change needed to increase or decrease a pattern size is known simply as “the grade.” Size differences in home-sewing patterns are typically based on a 2-inch grade, which means that the total difference between each size and the next is 2 inches. A 2-inch grade is what is shown in our examples.

A bodice pattern’s grade is applied differently to its top and bottom halves because the shoulder and upper chest areas only grow half the amount of its midsection area between the sizes. The top half is referred to as the half grade and the bottom half is referred to as the full grade.

Breakdown of a 2-inch grade ⁄16

⁄16

1

1

⁄16

⁄16

1

1

⁄16

1

Half grade 1 ⁄4 inch

⁄16

1

front

front ⁄16

1

⁄16

1

⁄16

1

⁄16

1

⁄8

1

⁄4

1

⁄4

1

⁄8

1

The Vertical grade

⁄8

⁄8

1

1

The full grade and the half grade The full grade is the amount of circumference increase or decrease from a bodice’s center front to side seam below the armscye. Above the armscye, the circumference amount increases or decreases half the amount of the full grade. To find the full grade (the amount that must be added or subtracted to each seam below the armscye), divide the grade (2 inches) by the number of seams in the full garment (four). Two divided by four equals 1⁄2 inch. To determine the half grade, divide the full grade amount (1⁄2 inch) in half, which equals 1⁄4 inch.

Patterns also grow incrementally lengthwise between sizes to maintain consistency in armscye and neckline depths and curves. The most typical vertical grade for a bodice is 5⁄16 inch, distributed throughout the pattern’s length as shown at left.

Full grade 1 ⁄2 inch

This shows how a pattern’s growth increments, adding up to the grade, are distributed.

Set up a workspace You’ll need a clear plastic grading ruler, a large piece of plain white paper taped to a flat work surface, a pattern, masking or painter’s tape, and a marker or pencil. You can use a full-size pattern or a half-size pattern as shown. On a large piece of paper, draw a line 2 inches from the lengthwise edge. Mark it “grainline.” Draw another line several inches from the paper’s righthand edge and perpendicular to the grainline; mark it “cross-grain.” Both lines are referred to as 0 position, and where they intersect is referred to as the 0/0 position.

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On the pattern, draw a line at or near the neckline, squared to the grainline (usually the center-back or center-front line). Mark a 0/0 position where the grainline and the cross-grain meet on the pattern.

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Align the grading ruler’s 0/0 position to the paper’s 0/0 position. Tape the ruler to the work surface along the edge marked “tape to table,” creating a hinge. Tape the front and back of the grading ruler to the surface. Place the pattern under the ruler, and align its 0/0 position to the paper’s 0/0 position.

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Cross-grain (0 position)

Grading ruler

Ruler’s and pattern’s 0/0 position

Grainline (0 position) Tape hinge

Grade a pattern The 2-inch grade shown illustrates how to move a master pattern under a grading ruler to increase the pattern at specific locations (see the facing page). The ruler remains stationary while the pattern moves counterclockwise around the 0/0 position to the different growth intervals. Professionals use the terms up/down and in/out to indicate the pattern’s movements around 0/0; we have used left/right and above/below for clarity. When you flip the ruler back on its hinge, hold the pattern firmly so it doesn’t shift.

Flip back the ruler. Mark the center neck and a short section of the neckline curve on the paper.

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Mark the centerfront neckline curve.

Directional arrows shown at right and in the photos indicate pattern movement under the ruler.

0/0 position

Flip the ruler back over the pattern. Move the pattern 1⁄16 inch to the right of the ruler’s 0 cross-grain. Also, move the pattern 1 ⁄16 inch above the ruler’s 0 grainline. Flip back the ruler and mark the shoulder/ neckline corner.

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Flip the ruler back over the pattern. Keep the pattern positioned on 1 ⁄16 to the right of the 0 crossgrain. Move the pattern 1 ⁄8 inch above the ruler’s 0 grainline. Flip back the ruler and mark the mid-shoulder area.

3

Mark the shoulder/ neckline corner.

1 ⁄16 inch above grainline

Shift the pattern 1 ⁄8 inch above the grainline and mark the mid-shoulder.

⁄8 inch above grainline

1

⁄16 inch right of 0 cross-grain

1

⁄16 inch right of cross-grain

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Keep the pattern 1⁄16 to the right of the 0 cross-grain. Move the pattern 1⁄4 inch above the ruler’s 0 grainline. Flip the ruler back and mark the shoulder/armhole position.

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Shoulder/armhole

Move the pattern 1⁄16 inch to the left of the ruler’s 0 cross-grain. At the same time, keep the pattern 1⁄4 inch above the 0 grainline. Flip the ruler back and mark the mid-armscye area and the armscye notch.

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Mark mid-armscye.

⁄4 inch above grainline

1

⁄4 inch above grainline

1

⁄16 left of 0 cross-grain

1

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Mark the underarm/ side seam.

Shift the pattern 1⁄8 inch to the left of the 0 crossgrain. Also, move the pattern 1⁄2 inch above the 0 grainline. Flip the ruler back and mark the underarm/ side-seam position.

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1 ⁄2 inch above grainline

⁄81⁄to left of 8 inch out0 cross-grain from grainline

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Move the pattern 1⁄4 inch to the left of the 0 cross-grain. At the same time, keep the pattern 1 ⁄2 inch above 0 grainline position. Flip the ruler back and mark the waist/sideseam position.

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Side seam at the waist

⁄2 inch above grainline

1

⁄4 inch left of 0 cross-grain

Keep the pattern 1⁄4 inch left of the 0 cross-grain. Shift it back to 1⁄8 inch above the ruler’s 0 grainline. Flip the ruler back and mark the waist dart notches. If your pattern has shirring, pleats, or tucks in lieu of a waist dart, mark them.

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Waist dart

⁄8 inch above 0 grainline

1

⁄4 inch left of 0 cross-grain

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Photos: Sloan Howard. Illustrations: (p. 42) ©Bonnie Hofkin 2014; (p. 44) Rosann Berry.

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Keep the pattern 1⁄4 inch left of the ruler’s 0 cross-grain position. At the same time, move the pattern back to the 0 grainline. Mark the center-front waist position.

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Move the pattern back to 1⁄8 inch left of the 0 cross-grain. Also, move the pattern 1⁄8 inch above the 0 grainline position. Flip the ruler back and mark the shoulder dart point and the waist dart point (make holes through the pattern).

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1 ⁄8 inch left of 0 cross-grain

Mark dart points.

1 ⁄8 inch above 0 grainline

On 0 grainline Center-front waist

Flip the ruler away, and overlay the original (master) pattern on the new pattern’s unfinished outline. Center the master between each of the marked intervals, and use it to blend the new pattern’s edges. At the armscye, match the notch and pivot for a smooth underarm curve. You can see how the pattern has expanded during this process at the growth intervals in the half grade and the full grade (see page 44). Be sure to grade the remaining bodice section.

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⁄4 inch left of 0 cross-grain

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Shift the pattern around the graded copy on the paper between the previously marked intervals and fill in the pattern edges.

Grading Tools Purchasing a grading machine, such as the Dario Grade-O Meter ($450 to $595), is an expensive proposition. If you intend to grade patterns frequently, however, it can be worth the cost, and you can find them on eBay or at SouthStarSupply.com. A grading machine makes moving a pattern between the growth intervals easier. This article teaches you how to use a grading ruler only (available at FashionPatterns.com), but the technique is essentially the same when using a grading machine.

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