---
title: "Basic Tutorial | Merge meshes with different borders"
slug: "cyclone-3dr-exercise-merge-meshes-with-different-borders"
updated: 2026-09-07T11:51:19Z
published: 2026-09-07T11:51:19Z
canonical: "rcdocs.leica-geosystems.com/cyclone-3dr-exercise-merge-meshes-with-different-borders"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://rcdocs.leica-geosystems.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Basic Tutorial | Merge meshes with different borders

> [!TIP]
> Open the file **MergeMeshes.3dr** ([download](https://www.cyclone3dr.com/download_helper.php?File=Cyclone3DRSampleData/MergeMeshes.3dr)).

This file contains 3 meshes, and the goal of the exercise is to merge the meshes together.

### With different borders and without overlapped area

Show only meshes **Part 1** and **Part 3**. As you can see, there is a gap between the two meshes. In order to merge them, we need to build a junction. Go to [Join 2 Contours](/v1/docs/cyclone-3dr-join2contoursc). Then click a point on each mesh border. Choose to continue with the entire contour. The result is not the expected one because the complete borders have been joined, but we want the junction to be only on the middle part.

Click the button **Restrict**, and then click on 2 points on the first contour to join in order to delimit the area. Then, click on a point on the wanted portion and press **Enter**. Do the same for the second contour.

![MergeMeshes_1.PNG](https://cdn.document360.io/820e11db-8ed5-45ae-ac86-f6b77dcb2aa7/Images/Documentation/MergeMeshes-1.PNG)

Define the portion to join

Then you can change tangency criteria. The best choice in this case is tangent **to the surface** for both contours. Select the option **Triangle Reorganization** in order to improve the result. Do not forget to select the option **Sew** in order to have only one mesh at the end.

Then click **OK, Exit** to validate. You can use the smoothing in order to improve the result on the sewing zone (Group command)(see section Local smoothing in the [Exercise: Improve global aspect and edges](/v1/docs/cyclone-3dr-exercise-improve-global-aspect-and-edges))

### With different borders and overlapping area

Undo as necessary to retrieve the initial state of the file. Show only meshes **Part 2** and **Part 3**. As you can see, there is an overlapping area between the two meshes. In order to merge the meshes, there are three possibilities:

- Remove triangles to create a gap between the two meshes (use the command [Clean / Separate Mesh](/v1/docs/cyclone-3dr-cleanseparatemeshc)), then apply the method described above **with different borders and without overlapped area.**
- Remove triangles to make the two borders strictly identical. To do that, select one mesh and the polyline **Section** and go to [Constraint Mesh](/v1/docs/cyclone-3dr-constraintmeshc). Uncheck **2D computation** and check **Cut in parts.** Do the same with the second mesh. This command will cut the meshes along the polyline. Then, show only the 2 biggest parts, select the two biggest meshes and go to [Merge Common Borders](/v1/docs/cyclone-3dr-mergebordersc) in order to create only one mesh.
- Select both meshes and go to [Stitch Meshes](/v1/docs/cyclone-3dr-stitchc). Keep the default values and click **Preview**. The command will automatically stitch meshes according to the overlapping area (note that this command is not limited to 2 meshes).

### Compound meshes

You can create only one object from different meshes, even if they do not have common borders. Select all the meshes you want to group and then go to [Group Mesh](/v1/docs/cyclone-3dr-groupmeshc). The associated command [Ungroup Mesh](/v1/docs/cyclone-3dr-ungroupmeshc) will allow you to retrieve all the independent parts.

> [!WARNING]
> ### Note
> 
> This command is useful, for example, if you want to compute an inspection and your reference contains several independent parts. Because to compute the inspection you can select only two objects: the one corresponding to the reference and the one corresponding to the measure.