So after two weeks of work and experimenting I have finally finished the parquet.
All the 120 pieces are dead square and equal in size, down to a error of .01mm.
So we made a total of 1200 pieces and only about 360-400 was usable.
Than the best work begun, laying the pieces and gluing edge to edge:
So after about 4 hours of intense concentration I was done.
And a close-up:
Tomorrow I will glue this up on a fibre board with a back of Brazilian Rosewood; got to have a nice underside to any table!