The tyWeld modifier can be used to weld vertices and cull overlapping faces of a mesh. It is especially helpful for welding/culling the interior faces of a mesh converted to tets with a tyMesher.
Weld vertices: controls whether vertices will be welded together by proximity.
Weld threshold: the maximum distance threshold between vertices in order for them to be welded together.
Remove isolated vertices: removes any vertices not connected to at least one face.
Open edges only: only vertices on open edges (edges connected to a single face) will be welded.
Weld all elements: all vertices will be considered weld candidates for each other.
Different elements only: vertices will only be welded together if they are parts of different elements.
Same element only: vertices will only be welded together if they are part of the same element.
Matching Vertex Mode: in matching vertex mode, face pairs will be culled if all of their vertices are within the distance threshold of each other, and the angle of their normals are within the normal threshold of each other.
Raycast Mode: in raycast mode, face pairs will be culled if a ray cast from the center of one of them hits the other within the distance threshold, and the angle of their normals are within the normal threshold of each other.
Dist thresh: the maximum distance between candidate face pairs.
Normal thresh: the maximum angle between the normals of candidate face pairs.
Use vertex selection: controls whether only selected vertices will be welded.
Soft sel thresh: vertices that are softly-selected must have a soft selection value above this threshold in order to be welded.