Filament material reelsThere are a wide range of materials available for the various types of additive manufacturing, but when it comes to FDM or Fused Deposition Modelling, there are currently three types of thermoplastic filament material that are most popular; PLA, nGen and ABS.
PLA is the easiest to use and is generally the material of choice when ever possible. It’s main draw back and limitation is that it starts to soften at a temperature (glass temp’) of about 60º C. Due to this there is a new material which has recently been released called Amphora AM3300 co-polyester, otherwise known as nGen. This  is becoming very popular as an alternative to PLA. nGen’s glass temperature is about 85º C, which is a lot more usable and not likely to soften if left out in the sun.
ABS is a very well known and widely used engineering polymer. When used for 3D printing it makes very good and durable products. Its main limitation is that due to its higher melting point, higher processing temperatures are required when printing with it. This can result in shrinkage distortion and warping of the final component. Various printing techniques can usually overcome these difficulties. However it can be a particular problem when there are large variations in cross section and thickness within the component.
Most of the patterns, core boxes and lettering illustrated on this web site are printed in ABS or nGen.
The following provides details of these three materials general characteristics:-
PLA (Poly lactic acid)
  • PLA has a glass transition temperature (the temperature that the plastic starts to soften) of about 60ºC
  • Created from processing a variety of plant products including corn, potatoes or sugar-beet, PLA is considered a more environmentally friendly plastic compared to petroleum based products.
  • Can be sanded and machined.
  • Can be painted with acrylic paints.
  • Can be joined with adhesives suitable for use on plastics. Super-glue is good due to its strength, ease of use, and quick drying time.
  • PLA is more brittle and less ductile than ABS and will tend to splinter and break where ABS may tend to bend, but generally similar force is required for either to fail.
  • Due to it’s brittle nature PLA isn’t recommended for tool handles or parts that will be dropped repeatedly, also parts that have very thin portions will break after bending slightly.
  • Printed PLA objects will generally have a glossier look and feel than ABS.
  • A wide range of colours available
Amphora AM3300 co-polyester (nGen)
  • A glass transition temperature of about 85º C
  • Tougher than PLA but a little less than ABS.
  • Currently available in 16 colours
We can not describe the benefits and properties of this new material better than the manufacturers, so take a look at their web site details:
ABS (Acrylonitrile butadiene styrene)
  • Made out of oil-based material
  • It is considered to have similar strength to PLA, but is more ductile and less prone to crack or break when bent.
  • Examples of injection mouldings using ABS range from car bumpers and motorcycle helmets to musical instruments, golf clubs and Lego.
  • ABS has a glass transition temperature (the temperature that the plastic starts to soften) of about 100º C
  • ABS glass transition temperature is higher than nGen (about 85º C) and PLA (about 60ºC), which makes parts printed in ABS more resistant to distortion under higher temperatures.
  • May be sanded and machined.
  • Can be painted with acrylic paints.
  • Can be joined with adhesives suitable for use on plastics. Super-glue is good due to its strength, ease of use, and quick drying time. ABS parts can also be joined with Acetone in the form of ABS Glue.
  • PLA is more brittle than ABS and will tend to splinter and break where ABS may tend to bend, but generally similar force is required for either to fail.
  • ABS is more ductile. It has more flex to it and it tends to bend rather than snap when put under pressure.
  • Objects that might be dropped, put in hot environments or used in a rough manner are perfect uses for ABS. In short it’s very good for most objects.
  • More limited range of colours available than PLA and nGen.

Filament colours