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Hello! Love this helmet im actually trying to make it for myself and a few friends for a local stores midnight release of the masterchief edition release next month. I just bought a Makerbot Z18, and I guess my question is how do I know if these parts are 1:1 scale? my initial look at this I just thought it was all one piece and id just scale it according to my head measurement but seeing it in several pieces how do I know if all the pieces are scaled to the proper size to fit together and on my head?