3D printing has come a very long way in a very short time. I remember first hearing about stereolithography (SLA) back in the late 1980s when I was an AutoCAD trainer. SLA was a method of using a laser to draw a pattern on a vat full of a UV (ultra-violet) sensitive resin, as it drew the laser caused the resin to harden and a shape was slowly produced. The machines, of course, were horrifyingly expensive and well out of the reach of the average Joe.
Fast forward to 2019 and we find that we can now purchase 3D printers for as little at $370 (or cheaper, but I would not recommend them), making 3D printing a possibility for everyone.
There are essentially two types of 3D printers for the home user, DLP and FDM. DLP stands for Digital Light Processing, FDM for Filament Deposit Manufacturing. DLP printers are the equivalent of SLA, in that that uses a vat of resin that is exposed to a UV light source via, essentially, a mobile phone display acting as a mask (to block or unblock the UV light). FDM printers use a spool of plastic filament that is deposited (by melting it) onto a build-plate using a robotic arm.
I personally spent over a month investigating the best value and best-reviewed 3D printers, before deciding to become a distributor for the AnyCubic range of 3D Printers.
DLP vs FDM
So I’m sure you are wondering what other differences the printer technology has. Well, glad you asked.
DLP printers have a very, very high level of printing detail. About 50x that of an FDM printer, however (currently) they have a small build volume. Build volume is the maximum size of the 3D part that can be printed.
DLP printers are best suited to the printing of very high detail, small parts such as character miniatures, dental moulds, jewellery and machine parts requiring a high level of detail and finish. In the example below, you can clearly see the difference in build quality between FDM and DLP.
However, the build volume, simplicity of use and range of printing materials for FDM printers is considerable and the print quality is improving all the time. If you can afford it, having both types of printers gives you the best of all worlds.
The Joy of Resins
Resins for DLP 3D printers come in a variety of colours, although they are all generally very smelly. You must use DLP printers in a well-ventilated area (although this also applies to a lesser extent to FDM printers).
Please take the time to watch this video on resin safety.
When looking to purchase resins there are a range of manufacturers and the benefits/costs of each are beyond the scope of this article. You can purchase the range of AnyCubic resins from the shop on this website, which have been manufactured and approved for use by AnyCubic with their printers.
Filaments for FDM
As mentioned previously, FDM printers use spools of plastic filament that is melted onto the build-plate. When you start looking into the range of filaments available, you will start to come across acronyms by the dozen.
ABS is short for Acrylonitrile Butadiene Styrene with a melting point of around 225 degrees Celsius. It is relatively strong, a little flexible and has a “glass transition temperature” of around 100 degrees (the temperature above which a plastic goes from it’s solid-state to a pliable state where it can lose its shape).
ABS is very suitable to 3D print functional parts such as spare parts for machines or objects that are exposed to high temperatures.
The downside of ABS is the smell it produces while being heated (ventilation essential) and that it expands and shrinks in the process of being heated and cooled down again. This shrinkage is a problem for 3D printing as it causes 3D prints to curl up while cooling too quickly (warping). ABS has to be printed on a heated build plate (preferably in an enclosed, heated build chamber) so it stays warm during printing and can cool down slowly when printing is done.
The AnyCubic Chiron has a heated build-plate to support this, although if you were intending to do significant amounts of printing with ABS it would be worth enclosing the printer to reduce heat loss.
PLA or Polylactic Acid is thermoplastic made from corn starch or sugar cane and is biodegradable, so it’s more environmentally-friendly than ABS, and as it flows a little better than ABS, you can print more detailed objects with it at higher print speeds. PLA prints have a relatively glossy surface compared to ABS, but the amount of gloss depends on the vendor, colour and print temperature.
As PLA is so widely available and being easier to print with than ABS, for the majority of jobs PLA is the best material for home and office 3D printing.
PLA also comes in blends that allow special material effects, such as bronze, copper, wood, glow-in-the-dark and many, many others.
PET (also known as PolyEthylene Terephthalate) is also available in many colours. It is a fairly stiff and very lightweight material, which is very strong and impact-resistant. You would have encountered it most often in the form of soda bottles. AnyCubic does not have a range of PET filaments, but there is a large range on eBay for you to select from.
When a 3D print is required to be very strong the use of Nylon (also called PA) is a good option. It usually prints in white and is available in different formulas. However, Nylons print at a high temperature of 245 – 250 degrees Celsius so your FDM printer needs to support the required nozzle temperature to support it.
Flexible filament is more like rubber. When it comes to Flexible Filament, it’s all about finding a balance between flexibility (softness) and printability as the printer needs to be able to lay down the material without the part flopping around.
This softness is sometimes indicated with a Shore value where a higher Shore value means less flexibility.
Thermoplastic elastomer (TPE) – sometimes referred to as thermoplastic rubber – is very flexible plastic. A lot of printers have difficulties printing with it, because of it’s softness which can result in extruder jams. A popular brand of TPE Filament is Ninjaflex.
Also known as Soft PLA, this is a modified, softer PLA plastic which is a generally stiffer than TPE. It’s available as Flex EcoPLA and other brands.
TPU stands for thermoplastic polyurethane and has many useful properties, including elasticity, transparency, and resistance to oil, grease and abrasion.