Q:

Can anyone explain why my normals have a mind of their own

I've tried flipping them, recalculating them and remaking the faces but i cant understand why the mesh still appears hollow, any ideas would be much appreciated
 

A:

Normals could have nothing to do with this: I think it's just a viewport visualization issue, due to the extremely wide clip you set in this file:

that's a huge clip interval you set! from 1 mm to 10000 km!
see what happens setting it on a smaller scale, like from 1 mm to 1 km!

...your mesh is interpreted as it should... isn't it?
Explain why this happens is outside of my knowledge, but I can suggest to leave clipping limit around "reasonable" limits, depending on the scene you are trying to visualize.

