Grading

Definition and Overview

Grading is the process of creating patterns in multiple sizes, such as S, M, and L, from a base-size pattern, also called a master pattern. Rather than simply enlarging or reducing each part by the same proportion, it is expanded while considering ease of wear, silhouette, and body-shape differences by part.

In apparel production, it is the process of reflecting the size specifications set in planning onto the pattern and turning them into data or paper patterns that can be cut in mass production. Because it affects both the look and comfort of the size range, it is closely related to pattern design.

Position in Product Development

In general, grading is performed after design, preparation of the specification sheet, creation of the base-size pattern, and sample verification, once the specifications have been finalized. After that, the size-specific patterns are used for marking, spreading, cutting, and sewing.

If you develop the range before the silhouette and dimensions of the base size are finalized, revisions may be needed for all sizes in the later process. Before grading, it is important to finalize the fit of the base size, seam allowance, darts, pockets, and other details as much as possible.

Workflow and Practical Points

First, based on the size chart, set the amount to increase or decrease between sizes for the bust, waist, hip, body length, sleeve length, and other measurements. This increase or decrease amount is sometimes called the pitch, and it is determined according to the item, target customer, fit, and the brand's size design.

Next, determine in which direction and by how much each reference point of the components should be moved. Not only the body, but also related components such as the collar, sleeve, facing, pocket, and interfacing must be kept consistent. Even when using CAD, confirm not only the set values but also the continuity of lines and shape after development.

For knitwear, stretch materials, and products that undergo garment washing, the material's stretch and shrinkage rate affect the finished size for each size. Based on the characteristics of the textile and sewing conditions, perform prototypes or post-wash checks as needed.

• Clearly distinguish and share the size chart and the actual and finished measurements of the base size.
• Check consistency for symmetrical components and components that pair between front and back.
• For button positions, buttonholes, pocket placement, and similar details, check not only the dimensions but also how they look.
• Leave the information needed for cutting and sewing, such as seam allowance, notches, and grainline, on the size-specific patterns.

Ordering and Quality Considerations

When requesting grading from an external pattern maker or factory, provide the finalized base-size pattern, size chart, specification sheet, development sizes, and required delivery format together. Since decisions may differ based on dimensions alone, also share which parts you want to change and for what purpose.

After delivery, do not just measure the main dimensions of each size; also check the patterns by overlaying them and verify sample garments in representative sizes. In particular, for the shoulder width, armhole, sleeve cap, crotch curve, and neckline, confirm that the balance and seam compatibility have not been compromised by the increases or decreases.

Differences from Similar Terms

A pattern is the actual paper pattern used to cut each component of a garment. Grading refers to the work of developing that pattern from the base size into multiple sizes. Therefore, pattern creation and grading are continuous tasks, but their purposes and processes are different.

Marking is the process of arranging the size-specific patterns efficiently according to the fabric width and grainline to create a cutting layout. Marking is done after the correct size-specific patterns have been created through grading. A toile is a trial garment used to examine a three-dimensional silhouette and specifications, and it is not the size range itself.

Frequently Asked Questions

From how many sizes is grading needed?

If production is done only in the base size, it is usually unnecessary, but it is needed when selling or producing multiple sizes. Decide the range not only by the number of sizes to be developed, but also by checking the target customer's body type, the item's fit, and the size standards required by the sales destination.

Is sample verification needed after grading?

Yes. Even if the development is numerically correct, changes in size can alter the silhouette, ease, and the appearance of the pocket and button positions. Check at least the representative sizes, and adjust the pattern and increase/decrease amounts as needed.

Can grading be outsourced with only the specification sheet?

The specification sheet is an important document, but usually the finalized base-size pattern and size chart are also required. The specification sheet should describe sewing methods and accessory positions, while the pattern should clearly indicate shape, seam allowance, notches, and other information. Confirm the format of the delivery data before placing the request.