甘比英文拓展写作-3D printer-zln_九月

Day 18 3D printer

3D printing technology makes it possible to make prototype less time-consuming and cheaper. But do you know how 3D printer works? Let’s take a brief look.

Simply, 3D printer works a bit like inkjets and builds up 3D models layer by layer following a pattern from a digital file. At first, you should have a designed model drawn by three-dimensional modeling software like CAD in the computer. The auto-separated 2D sections of the model drawing in computer instruct the machine to build up the real model. The most important components of a 3D printer include the print head and nozzle, as well as a baseplate. The head and nozzle, or extruder body, are installed along two rails where they can move in one direction horizontally. Coordinately, the baseplate, which is mostly a piece of glass covered with a film to protect the printer bed and separate the finished model easily, can slide in the perpendicular direction horizontally. It is very much like the well-known inkjet printer operated from a computer, yet the “ink” in 3D printer is real plastic instead of colored water. The raw materials are supposed to be some thermoplastics which are soft and bendable when heat but hard when cold. The typical one is ABS plastic which has been used widely in plastic computer parts like mouse and keyboard.

The creation is different from conventional wooden prototype making by starting off a block of solid wood and carving inside, it proceeds by depositing the molten plastic layer by layer from the bottom upward. It uses a method called fused depositional modeling (FDM) which is the main technology in 3D printing. When the printer works, the plastic is melted to a rod by the print head and then the rod is extruded through the tiny nozzle which moves around precisely under computer control. It prints one layer at a time, and after one layer is done, the printer bed lowers a little. Thus it piles up lots of two-dimensional, cross-sectional layers sitting one on top of another. When all layers are finished, the 3D prototype making is done.

2017.2.6