COMPUTER CORNER

Bill Gillespie
Rosemary McDowall

With 3D printers becoming more common in schools we thought we would write a “3D Printing for Dummies” column for teachers who haven’t heard about the technology or those who are looking to introduce a 3D printer to their school.

What is a 3D printer? 3D printing is the process of turning a digital file into a three-dimensional shape.

How does it work? The computer takes the digital image and “cuts” it into slices or layers. The printer then prints each layer to build up a composite 3D structure or deletes area to form the structure. In this way the printer can print moveable parts such as hinges by leaving gaps in the right places.

Types of 3D printing: There are a number of different types of printing technologies including Stereolithography, Digital Light Processing (DLP), Laser Sintering or Laser Melting, Electron Beam Melting (EBM), Selective Deposition Lamination (SDL) and ExtrusionFused Deposition Modelling (FDM) Freeform Fabrication (FFF). There are also two types of 3D inkjet printing, Binder and Material Jetting. The most common type of 3D printing being conducted in schools is ExtrusionFDMFFF printing.

There are a number of different types of 3D printing technologies

How does ExtrusionFDMFFF printing work? The starting point for 3D printing is a 3D model file. This can be created with any 3D modelling software. In schools, this is usually a computer-aided drawing (CAD) program. The file is then sent to the printer. A plastic filament is heated within the printer and extruded a layer at a time on a platform according to the data from the 3D file. These layers are then built up to create the 3D object.

Do I have to use a CAD program to create a 3D model file? No, a file can be created using a 3D scanner. These scanners work by detecting the changes to the light that is shown on the object and converting the changes into a digital file. The file can then be edited within a 3D software program.

The future for 3D printing: It is just in its infancy. The first patent for 3D printing was logged in 1986. It is only in this century that 3D printing is beginning to make its mark in the consumer field. In the medical field, 3D printing is being used to create replacement parts onto which cells can be grown.

NASA is researching the use of 3D printing for space travel. Rather than sending large structures to distant planets it may be possible to “print” the materials at the destination.

Microsoft and Google have recently enabled their hardware to perform 3D scanning so it may be possible for smart devices such as phones to digitise 3D objects. This will mean that creating a 3D file will be as easy as taking a photo.

Currently we are using 3D printers worth more than $1000 to create objects that are worth 20 cents, and this is taking up to an hour. It is a rapidly changing field and the future is hard to imagine.

Bill Gillespie teaches at Elanora Heights PS and and Rosemary McDowall The Forest High. They can be contacted at computer_corner2000@yahoo.com