kleinARt

AngelSTEP brings STEP and IGES import and export to Blender, turning CAD data into watertight meshes with crisp normals. It adds per-part tessellation, defeaturing, CAD-based UVs, assembly tools and real STEP export in one self-contained add-on.

Insideout - Delete Inside Geometry is a Blender add-on from kleinARt that removes hidden interior faces and fully enclosed objects using visibility ray-casting, leaving the visible surface, UVs, normals and materials untouched.

Max Stack - Max Modifiers And Stack brings 27 Max-style modifiers to Blender that work as one system, with selections flowing down the stack, live viewport gizmos driving them, and a single panel showing the logic.