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Reading bank 25 © Oxford University Press
3-D printing
Turning computer images into plastic models
Since the 1990s, engineers have used 
3-D printing to make models of complex 
designs. More recently, 3-D printing has 
been used to make objects for actual use, 
not just models. For example, doctors 
have used 3-D printing to make artificial 
body parts such as bones and joints. The 
process – called rapid prototyping – is 
still not widely used. But it’s becoming 
more common and techniques are being 
improved constantly.
And now, three-dimensional printing at home is a reality. You buy and bring 
home a 3-D printer, download a design from the Internet, and create plastic 
objects in your own home. Here’s what you do:
1 Prepare the printer by loading it with plastic wire. The wire comes in ten 
colours. You also have to spread glue on the print platform. 
2 Search the Internet for designs of objects that can be 3-D printed. Printer 
manufacturer Cubify has a wide selection at cubify.com, and others are 
available elsewhere. Designs include toys and games, jewellery, cups, 
lampshades, and many other things.
3 Using the 3-D printer’s software, convert the design to a set of 
instructions for building the object. The software works out any special 
supports that might be needed as the object is printed. 
4 Press ‘Print’ and watch the printer create your design. 
5 Let the plastic cool off, and enjoy your creation. 
So how does it work? The printer heats the plastic wire until it’s soft. The 
printer tip is heated to 300 °C, so when the plastic passes through it, it 
becomes even softer. The software tells the tip of the printer where to move 
to build up the object line-by-line. The printer tip can move up, down, and 
sideways, so it can go anywhere the software tells it to. 
The 3-D printer doesn’t make solid plastic objects. Instead, they are mostly 
hollow, with a kind of grid structure between the two walls of plastic. This 
makes the object strong and lightweight, and also reduces the amount of 
plastic needed to print it. 
There’s an important difference between 3-D printing in medicine and 
industry and 3-D printing at home: engineers and doctors use it to create 
things they really need. But for now, at least, the things you can print in plastic 
at home aren’t especially useful.
 20 Plastics
1 Answer the questions.
1 What plastic objects do you have 
with you, or can you see around 
you, right now?
2 Could any of those objects 
possibly be made of a different 
material? What material would 
work?
3 Have you heard anything about 
3-D printers? If so, what do you 
know about them? If not, can you 
guess what a 3-D printer might 
do?
2 Read the text. Complete the 
sentences with the words below.
 3-D printers designs 
doctors engineers 
instructions objects 
wires
1 were the first people 
to use 3-D printing.
2 now use 3-D printing 
to make objects that injured 
people need.
3 A 3-D printer uses coloured plastic 
 to make objects.
4 can be downloaded 
from the Internet.
5 The printer’s software creates 
 for building objects.
6 The aren’t solid 
plastic – they’re hollow. 
7 for the home don’t 
make useful objects at the 
moment.
3 If you had a 3-D printer at home, 
what would you use it to make?