Technical

Size Chart Generator for CAD Based Pattern Making Systems

Generate measurement specifications compatible with Gerber, Lectra, Optitex, and industry-standard CAD software. Professional grading tables for digital pattern making.

January 2025 11 min read CAD/Technical
Size chart generator for CAD pattern making systems

CAD System Compatibility

Gerber

AccuMark

Lectra

Modaris

Optitex

PDS

CLO

3D

Browzwear

VStitcher

TUKAcad

2D/3D

Modern pattern making relies on CAD systems for precision and efficiency. Size chart tools provide the measurement specifications and grading rules that CAD operators need to create accurately graded patterns for the full size range.

Pattern Grading Fundamentals

Pattern grading fundamentals

Base Size Pattern

Pattern developed in a single size (usually M or median) that serves as the foundation for grading.

Grade Rules

Incremental X/Y changes applied at each grading point to scale the pattern between sizes.

Nested Grade

Full size range patterns nested together for marker planning and production cutting.

From Size Chart to Grade Rules

Size chart to grade rules

Size specifications translate to grade rules:

Measurement S M L XL Grade
Chest 36" 38" 40" 42" 2"
Waist 30" 32" 34" 36" 2"
Length 27" 28" 29" 30" 1"

Grade Rule Calculation

The grade increment (2" chest) is distributed across grading points on the pattern. For a chest measurement, this might be 0.5" at each of 4 grading points (front/back, left/right).

Export Formats for CAD

CAD export formats

Excel/CSV

Standard format importable by most CAD systems

  • • Measurement tables
  • • Grade increment data
  • • Size range definitions

PDF Spec Sheets

Visual reference for CAD operators

  • • Measurement diagrams
  • • Grade rule summaries
  • • POM instructions

CAD Workflow Integration

CAD workflow integration
1

Generate Size Specifications

Create complete size chart with measurements and grade increments using the size chart tool.

2

Export Grade Data

Download Excel/CSV with grade increments formatted for CAD import.

3

Import to CAD System

CAD operator imports data and translates to grade rule tables in the software.

4

Apply to Patterns

Grade rules applied to base pattern generates full size range automatically.

CAD-Ready Size Specifications

Generate grade rules and measurement specs compatible with industry CAD systems.

Start CAD Specs

Frequently Asked Questions

What CAD systems are used for pattern making?
Major CAD pattern making systems include Gerber AccuMark, Lectra Modaris, Optitex, CLO/Marvelous Designer for 3D, Browzwear VStitcher, and TUKAcad. Each has different file format requirements but all need accurate size specifications for grading operations.
How do size charts integrate with CAD software?
Size charts provide measurement targets and grading rules that CAD operators input into grading tables within the software. Exports in Excel/CSV format can be imported into many CAD systems directly. Grade rule tables define how patterns scale between sizes at each grading point.
What is pattern grading in CAD systems?
Pattern grading is the process of systematically increasing or decreasing pattern piece dimensions to create the full size range from a single base pattern. CAD systems use grade rules—the incremental changes at each grading point—derived from size chart specifications.
Can size chart tools export CAD-compatible formats?
Yes, professional size chart tools export Excel, CSV, and structured data formats that CAD operators can use to populate grading tables. The measurement specs define the targets; CAD operators translate these specifications into pattern-level adjustments at grading points.
How do grade rules relate to size specifications?
Grade rules are derived directly from size specifications. The difference between sizes in the spec (e.g., a 2-inch chest increment between M and L) determines the grade rule applied at corresponding points on the pattern to achieve that dimensional change.