Polylactic acid (PLA) is popular in 3D printing as it cools and sets quickly. Unlike ABS plastic, it is biodegradable and therefore better for the environment. It can be used to build support structures for other printouts, as it can then be dissolved leaving no marks.
76% have it
13. Prints in PVA
Polyvinyl Acetate is another form of plastic used in 3d printing similar to ABS. It can be used to build support structures for other prints, as it can then be dissolved leaving no marks.
14% have it
14. nozzle size
The smaller the nozzle, the more detailed the final product can be. However, when speed of printing is of greater importance than detail, a larger nozzle may be preferable.
More extruder heads will allow you to use different colours or different types of material at the same time. A second extruder is also required to build PVA/PLA support structures around items as they are printed.