Despite being a relatively new technology, at least from an uptake point of view, most people will know that 3D printers create three-dimensional items using layers of material placed one on top of another. The material can be one of a number of things from plastic to metal, cement to glued paper, ceramics and sometimes even combinations of these items.
The most common type of 3D printers lay down layers of plastic, either as single-strand thin-walled lines or, depending on application and use of the object, thicker-walled lattices which provide greater structural strength. The beauty of plastic is that it is very versatile, readily available and very often inert for use in food packaging, medical applications and various other fields where other materials might pose a health or safety hazard.
Currently there are currently two main types of plastic used in 3D printing, ABS or Acrylonitrile Butadiene Styrene and PLA or Polylactic Acid. These two plastics offer their own specific advantages and will be selected according the application required. That said, ABS is being used less and less due to the fact that it is expensive, requires a high melting point and can only be used in a closed chamber printing system due to the toxic fumes created when the plastic is melted.
This has, until now, left PLA which was favoured for the fact that it can be used in open-air operating environments because it does not create any toxic fumes. It also does not require a pre-heated printing bed, is biodegradable in the right conditions due to being made from plant-based materials and, offers almost the same strength as ABS, with increased flexibility.
The downfall with PLA is that it is not resistant to water, chemicals, fatigue, heat and UV light rays. In normal indoor environments it is perfectly adequate but does fall short in less than perfect conditions.
So, what is the alternative? PET or Polyehtyleneterephthalate is another commonly found plastic which has many of the same features as ABS but without the negative side effects of toxic fumes, high cost and the requirement of closed printing chamber. However, it is not as strong as ABS nor as flexible as PLA. There is, however, a solution. The addition of Glycol to the PET to make PETG increases the strength and improves the flexibility creating a 3D printable filament which is as good, or even better, than PLA and the only negative is that it is not biodegradable.
PETG is not only stronger than PET but it is also more flexible. It also provides resistance to heat, UV light, chemicals, water and fatigue better than PLA which makes it suitable to some outdoor applications. The UV and heat resistance is less than ABS, however, it is sufficient to provide an average two-year lifespan in these conditions.
PETG does require a pre-heated printing bed or table which means that it can only be used with printers which have this as standard or as an option. This means that it cannot be used with all printers.
There is a printer available on the local market which can be used with both PLA and PETG. The AM.CO.ZA PrintUP 3D printer from Advanced Machinery can use both types of filament interchangeably due to the fact that it has a pre-heat table which can be turned on and off depending on which type of filament is used. This offers those customers who have these printers increased flexibility in their production capabilities.
For those customers who are looking to invest in a 3D printing system, they should consider a printer which is capable of handling PETG due to the increased advantages which it offers. And it you already have a printer capable of handling this innovative filament, then you are well on your way realising the benefits that the latest technology can offer.