‘What is support in 3D printing?’ is one of the most asked questions when working with clients. In this section, we’ll show what’s accepted to call supports and what types of supports are currently there.
Support material is an auxiliary material used in 3D printing for constructing complex objects and improving the quality and stability of modeling. 3D printing of models with cavities, overhanging structures, complex detalization, thin walls or laps, and other difficult details is impossible without the use of support.
Simply said, support serves as a particular temporary foundation for an item printed. Layer-by-layer building supposes that every following layer of the item relies on the previous one. In the case when the backing is not provided by the item design under the first layer in one or another place, support comes in.
How to determine where support is necessary?
This is done automatically with software, which comes with all professional 3D printers. You just need to upload an STL file and the software will estimate where the use of support material is required for the high-quality modeling. It should be noted that the majority of software also allows the user to edit the number and location of support structures. Software is directly tied to 3D printer capabilities and will automatically show you where support is needed where is not.
Besides, the software estimates the amount of required support material before starting the printing.
If we disagree with the automatic estimate of support by the software, here comes software where we can arrange supports manually. You can see below the picture of the manual constructing of supports in AutoDesk MeshMixer.
Types of support materials
There are 2 types of soluble support materials, such as HIPS and PVA. These types of plastics are used for printing supports in complex models where the high quality of the end product is critical.
Every type of plastics has its advantages and disadvantages.
So, for example, HIPS can be used as both main and support material. This plastic is soluble in limonene meaning it fits printing supports where ABS is the main plastic since they don’t interreact. There are also disadvantages – the high cost of limonene.
PVA, on the contrary, is used solely as support material. It is well soluble in water and compatible only with plastic where PLA is the main material. But there are two important differences from HIPS – a high cost of the material and more simplified post-treatment of the finished item.
The excessive material is chipped off, sawn off, stripped off. in this case, the same material the model is built from is used as support. But to simplify its further removal and decrease the model material consumption, support is made in a more thinned way as compared to the object. It has less density and strength sufficient only for the temporary bearing of the weight of the object built.
The material is being smelted and flows out when heating (the temperature is much less than the temperature of the main object deformation). It usually has the wax foundation. Advantages: softness, the accuracy of the application. It’s used in photopolymer and wax ProJet 3D printers of the 3D Systems company.
We should also mention 3D printing powder technologies. In this case, the same material is used as both support and main one. However, the part of powder, which was “support”, can be re-used as the main material after treatment. Thanks to that, these technologies are almost non-waste. The only exception is 3D printing with metal. When metal printing, metal shrinkage should be taken into account. You need to fix the part with support so it won’t twist or distort in the course of printing.