How do you check and fix UV overlap in Blender using the UV editor?

1 Mark seams and unwrap

The first step to avoid UV overlap is to mark the seams of your model. Seams are the edges that define where the UV map will be cut and unfolded. You can mark seams by selecting the edges in edit mode and pressing Ctrl+E and choosing Mark Seam. Once you have marked all the seams, you can unwrap your model by pressing U and choosing Unwrap. This will create a UV map in the UV editor, where you can see how the faces of your model are laid out on the 2D plane.

2 Check for overlap

To check for overlap, you can use the UV editor's overlay options. In the top right corner of the UV editor, click on the View tab and enable Stretching. This will show you how much the UV faces are stretched or compressed compared to the 3D model. The more blue the faces are, the less stretched they are. The more red the faces are, the more stretched they are. You can also enable Overlap to see which faces are overlapping. The overlapping faces will be highlighted in red. You can also use the UV Sync Selection option to see which faces in the 3D view correspond to the UV faces in the UV editor.

3 Fix overlap

To fix overlap, you can use the UV editor's tools to move, scale, rotate, or pin the UV faces. You can select the UV faces by pressing A, L, or B, and use the G, S, or R keys to transform them. You can also use the UV Sculpt tool to relax or smooth the UV faces by pressing Ctrl+Tab and choosing Sculpt Mode. You can pin the UV faces by pressing P, which will prevent them from moving when you unwrap again. You can also use the Live Unwrap option to see how the UV map changes as you adjust the seams or the UV faces. To apply the changes, press U and choose Unwrap again.

4 Use a test grid

Another way to check and fix UV overlap is to use a test grid texture. A test grid is a texture that has numbers, letters, or colors that help you see how the texture is mapped to the model. You can download a test grid texture from the internet, or create one in Blender using the Texture Paint mode. To use a test grid texture, you need to create a material for your model and assign the texture to it. Then, in the UV editor, you can see how the test grid is displayed on the UV map. You can use the same tools as before to fix any overlap, distortion, or stretching.

5 Use the UV Toolkit

Blender also has a UV Toolkit that provides more options and tools for editing the UV map. You can access the UV Toolkit by pressing N in the UV editor and choosing the Tool tab. The UV Toolkit has several categories, such as Align, Stitch, Pack, Snap, and Weld, that allow you to manipulate the UV faces more precisely and efficiently. For example, you can use the Align tool to align the UV faces horizontally or vertically, or use the Stitch tool to merge the UV faces along a seam. You can also use the Pack tool to arrange the UV faces within the UV bounds, or use the Snap tool to snap the UV faces to a grid or to each other.

6 Use addons

Finally, you can also use addons to enhance your UV mapping workflow and avoid overlap. Addons are extensions that add extra features or functions to Blender. You can find and install addons from the Preferences window, under the Add-ons tab. Some examples of addons that can help you with UV mapping are TexTools, UV Squares, and UV Packmaster. These addons offer more options and tools for creating, editing, and packing the UV map, such as baking, straightening, relaxing, or optimizing the UV layout.