Thanks for your positive comment Andrew 
The 2 small square blanks just have a internal V cut on one end of a blank & an external V cut on the end of the other, so they are then glued together pushing one V into another >> . The radius shape appears as it's turned, on this one I dry clamped the 2 blanks together with a piece of pop can aluminium between them to form the shape in the aluminium, then disassembled & reassembled this time gluing with CA.
The dots are aluminium welding rod, these were initially glued in with epoxy but the heat of drilling caused one to fall out so it was re-glued with CA & then thin CA run round all the dots just to be on the safe side.
HTH.