This technical-scientific thesis deals with the development and construction of a scalable reprap-system. The scalable structure of the 3d printer allows to expand the size of the printer and also enables a flexible mounting of different print heads. Minor modifications allow to change the number of print heads and even other types of print heads are mountable. The frame consists of purchasable aluminum profiles. The housing elements, which are mounted on the frame, protect and isolate the print area against influences from outside. The reprap-system works by means of the fused-deposition-modeling-principle, enabling cost-effective production of any three-dimensional polymer components.