This is the Tiaratop, the mind-controlled and mind-controlling computer from Homestuck! This same model can also be used for the crown worn by fushia-blooded trolls like Feferi and )-(IC.
As a simple, one-part model, there is no construction required. However, it does need to be painted because the model does not fit within the boundary box for colored plastic. Right now, this model is only available for printing in plastic. While the metals may seem more realistic, the thickness of the model would make it far too heavy. (Also the price would be over $450.) I can make a thinner version for printing in metal on request. The space for the head is a circle of diameter 7.266 inches. I can scale it for you if you ask.