How to Insert a Fly Zipper in CLO3D

How do you construct a fly zipper in CLO3D?

A convincing trouser fly in CLO3D involves more than simply adding a zipper to the centre front. The fly construction also needs the correct pattern pieces, folds, layering and stitching so that the finished garment behaves and looks like a real trouser opening.

In this step-by-step tutorial, I start with a basic trouser block and build the fly construction from the pattern stage through to the finished zipper. I cover the fly pieces, internal lines, folds, layer settings and zipper placement, as well as some of the small adjustments that can help tidy the final simulation.

This is particularly useful if you are using CLO3D for pattern development or technical garment construction rather than only for visual presentation.

What I cover in the tutorial

• Understanding the construction of a trouser fly
• Starting from a basic trouser block
• Creating the fly and underlap pieces
• Tracing pattern pieces for the fly construction
• Adding stitching and merging pattern areas where needed
• Creating fold lines and controlling the fly shape
• Using Select Mesh to subdivide and strengthen specific areas
• Managing pattern layers
• Creating accurate zipper placement lines
• Adding the zipper with CLO’s Zipper tool
• Adding additional stitching and fastening details
• Adjusting the slider and puller visibility
• Using pins and simulation adjustments to neaten the result
• Troubleshooting puckering and finishing details

Using CLO3D as part of a wider pattern-making workflow? I’ve also pulled together 10 CLO3D Tools & Workflows for Pattern Makers, covering drafting, seam checks, fit review, grading and production preparation.

Want to build more confidence editing patterns directly in CLO3D? My How to Cut Patterns in CLO3D tutorial shows how to use Internal Lines, Cut, Cut & Sew and StyleLines to create new panels and construction lines.

Version note: This tutorial was recorded in 2024. The core fly-construction workflow and CLO3D Zipper tool are still relevant, although some tool locations and zipper properties may look different in newer versions. Current CLO versions also provide more detailed control over zipper styles, including zipper type, gauge, slider, puller and stopper properties.