Welder provides tools for generating weld seams on hard surface models in Blender. It automates the process of creating welds along object intersections or selected edges, and includes an option to draw welds free-hand across surfaces. The tool is designed to add realistic structural detailing to mechanical and industrial models.

Users can choose from seven distinct weld types and customize the cross-section shape using a built-in curve editor. Additional features include smooth surface blending for seamless integration with the base geometry and a decal mode for optimizing welds on low-poly meshes.