I'm trying to combine two different meshes, and in these three small parts one mesh has more vertices than the other. This makes it so I can't just pull the vertices together and remove doubles, and it creates these gaps in the mesh. How do I fix this? Can I add more vertices to the other mesh?
Do not create new vertices, just snap the existing ones to each other. Activate snapping (Shift S), choose Vertex, choose Vertex select(Ctrl Tab 1), select one vertex, press G to move and move it closer to another vertex, it will snap to it. Then make sure to remove doubles to avoid differences in weights
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