3D printing of new metallised plastics is investigated as a means to realise rapid creation of reflective optics for the terahertz regime. The suitability of three commercially available candidate materials was tested across a range of systems which span from 0.2 to 10 THz. Simple reflective planes were printed and characterised by spectroscopy and microscopy. Samples were polished which is shown to give a dramatic improvement to the reflectivity for these materials. The results indicate that metallised plastics have potential uses in low frequency rapid prototyping of reflective optics.