How to Make Garment Pattern Based on Fabric Shrinkage || Textile Floor

Pattern making is a fundamental part of garment manufacturing, directly impacting the fit and accuracy of a finished garment. The process is shaped by fabric shrinkage and sewing allowances, with multiple pattern sets being used in some cases to accommodate variations in shrinkage. The goal is to create patterns that meet the buyer's precise specifications, ensuring garments are properly sized and fit well. In this article, we will explore the importance of fabric shrinkage in garment pattern making and how it affects measurement accuracy.

Understanding Pattern Making Rules for Garment Manufacturing

Garment patterns are highly sensitive to fit, so determining fabric shrinkage is the first step in creating a pattern. Based on the shrinkage percentage, different patterns may need to be created for fabrics with varying shrinkage rates. If the shrinkage difference is over 2%, 3%, or 4%, separate patterns are required for each fabric group. However, if the shrinkage is within an acceptable range, a single pattern may suffice for the entire lot.

Stages of Pattern Making for Garments with Varying Shrinkage

® Grouping Fabrics by Shrinkage Accurate shrinkage analysis is crucial. Fabrics are grouped into categories based on their shrinkage rates, typically between -2% to 8%. Common groupings include 2%-5% shrinkage and 6%-8% shrinkage, which guide the development of distinct patterns for each fabric group.

® Creating Separate Patterns for Each Shrinkage Group Once the shrinkage groups are defined, unique patterns (e.g., P1, P2) are created for each group. These patterns are adjusted to account for the different shrinkage rates of the fabrics, ensuring each garment's fit is accurate and consistent.

® Pre-Wash Measurement Specifications Prior to washing, pre-wash garment measurements are calculated based on the shrinkage percentage. The pattern is adjusted accordingly in the CAD (Computer-Aided Design) system and is labeled with the appropriate group number (e.g., P1 or P2). These specifications are then sent to the sewing section for verification during the garment assembly.

® Sewing Stage Garment Measurements During the sewing process, garments are measured according to the pre-wash specifications provided by the CAD team. The quality control manager checks the measurements to ensure they meet the before-wash standards. Any discrepancies are addressed, and corrective actions are taken.

® Corrective Actions for Measurement Deviations If a garment does not meet the specified measurements during the sewing process, the cause of the discrepancy is identified, and corrective measures are implemented. All actions are documented to prevent similar issues in future production runs.

By following these steps, garment manufacturers ensure that patterns are accurately created, considering fabric shrinkage and maintaining measurement precision. This results in garments that are well-fitted and meet buyer specifications.

The Garment Pattern Making Process

Pattern making is the process of making templates for the different components or parts of a garment, such as fabric, lining, and interlining. These templates are then used to trace the design onto fabric or marker paper, enabling the garment to be constructed. 

A. Block Pattern: The Foundation of Garment Design

The block pattern or basic block, forms the foundation for all garment designs. It is created based on standard body measurements, without any added design features. The block pattern is tailored to various body types, ages, and genders.

Block Pattern Making Methods:

® Flat Method: This method uses technical drawings to create the key parts of the garment, ensuring accurate proportions. The pattern can be developed manually or through computerized systems.

® Modeling Method: Widely used in the garment industry, this method involves creating a block pattern based on standard measurements, often with a mannequin. The result, called a "toile," is adjusted as needed and then traced onto hard paper to create the block pattern.

B. Working Pattern: Modifying the Block Pattern for Production

The working pattern is derived from the block pattern and modified to include elements like sewing allowances, pleat locations, and fabric shrinkage considerations. This pattern is used for cutting the each garment part. Once the working pattern is developed, a sample garment is created for fit testing.

Grading Garment Patterns for Different Sizes

Grading is the process of creating patterns for different garment sizes by either increasing or decreasing the original pattern size. The goal is to maintain the shape and fit of the garment while adjusting it to various body sizes.

Grading Methods:

®  Manual Grading: In this traditional method, a pattern template is used to create individual sizes. Vertical and horizontal marks are added to the pattern to adjust its dimensions.

®  Computer-Aided Grading: This automated system uses algorithms to generate patterns for multiple sizes. The system calculates the pattern based on size charts and allows for visual assessment and adjustment on a computer screen.

Important Terms in Garment Pattern Making

ü  Darts: Darts are used to remove excess fabric, allowing the garment to fit better and conform to the shape of the body.

ü  Grain Line: The grain line indicates the direction of the fabric's weave. This affects how the pattern pieces are placed on the fabric during cutting.

ü  Drill Holes: These small holes mark where components like pockets or zippers should be placed on the garment.

ü  Notches: Notches are small cuts or marks that indicate where different parts of the garment should be joined together during the sewing process.

By following the pattern making steps outlined above, garment manufacturers can ensure that each garment is accurately sized, fits well, and meets quality standards. The integration of fabric shrinkage considerations, grading, and pattern modification methods guarantees consistency and precision in the final product.