My character sits in a chair and ties shoes. When I zoom in the camera for a close-up of a shoe, the hands/arms disappear but the shoes remain visible. Near clipping of .01 did not help, nor any culling settings.
Eventually I tried ticking “Update when offscreen” on the arms, and arms/hands no longer disappear – problem solved. Although I don’t really understand why it happened. Character has several separate meshes parented to one armature, so maybe it confused Unity. I tried attaching a sphere to a hand bone and it didn’t disappear (until I zoomed the camera past it).
Lots of Google searches didn’t really help – just trial and error on many settings.