#20 The Cup Size Adjustment for a Dartless Pattern

How to Do a Full Bust Adjustment Without Darts

Adjusting for a full bust doesn’t always require traditional darts. If your sewing pattern uses gathers or pleats instead of dart shaping—like the Belle sewing pattern from In-House Patterns—this tutorial will show you how to modify the pattern for a larger (or smaller) cup size while maintaining a clean silhouette and original garment shape.

What You’ll Learn

In this tutorial, you’ll learn how to:

• Identify the bust point on a pattern without darts
• Use pleats and gathers as dart alternatives
• Add bust fullness evenly across the pattern
• Make proportional length adjustments
• Avoid altering the waist and hip girth

Why This Method Works

Traditional full bust adjustments rely on bust darts to establish bust volume. But when a design lacks these darts, shaping must be added in more creative ways. This method leverages existing pleats and gathers to insert fullness exactly where you need it—without distorting style lines or affecting hem measurements.

Step Highlights

1. Start with length adjustments before contouring
2. Create slash lines through pleats and across the bust
3. Distribute added width in multiple areas for balanced shaping
4. Add corresponding length to maintain balance
5. Refine all seam and cut lines for accurate sewing

What Makes This Technique Valuable

This approach allows you to make a full bust adjustment without impacting the hip or waist measurements—ideal for those wanting to tailor fit at the bust without increasing overall garment volume. It's a clean, efficient way to go up one cup size using smart pattern manipulation.

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Chat with you soon,
Alexandra