The difference between 3D printing and CNC machining 1. Differences in materials The main materials for 3D printing include liquid resin (SLA), nylon powder (SLS), metal powder (SLM), gypsum powder (full-color printing), sandstone powder (full-color printing), wire (DFM), and sheet (LOM) etc. Liquid resin, nylon powder and metal powder occupy the vast majority of the