You sneaky beaver! you lured me into opening this thread.
Stefan Pochman once introduced a 7x7x7 cube design that has proportional cubies and is perfectly cubical. His idea was to conect the cubies with pivots that can extend and pull in I think. Maybe there was more complexity and thinking in it than I make it sound right now. Anyway I forgot about his "super cube" stickering and was really wondering what I might find here.
But have fun solving that anyway.