3D printing technology allows for the production of objects with complex geometries, but some designs may have parts that hang in the air due to gravity. In these cases, support structures come into play. Supports ensure a successful outcome by supporting these overhanging parts during printing. However, the use of supports is not always necessary and can negatively affect print quality if used incorrectly. In this guide, we will cover topics such as when to use supports in 3D printing, different types of supports and their advantages/disadvantages, support settings in popular slicing software like Cura and PrusaSlicer, and how to remove supports cleanly.
When Are Supports Needed?
Basically, if a part of an object hangs in the air at an angle greater than 45 degrees, supports are needed. This angle can vary depending on the properties of the material used and the print settings. For example, materials printed at higher temperatures, such as ABS, may have more tendency to sag than PLA and thus may require support even at lower angles. Additionally, factors such as print speed and layer height can also affect the need for supports. Slower print speeds and lower layer heights can reduce the need for supports by allowing the material to cool better and sag less.
Types of Supports and Their Characteristics
The main types of supports used in 3D printing are:
- Linear Supports: The simplest type of support, generally used to support flat surfaces. They can be created quickly and easily but have high material consumption and can be difficult to remove.
- Tree Supports: Ideal for supporting objects with more complex geometries. They provide support by branching out, similar to a natural tree structure. Material consumption is lower compared to linear supports, and they are easier to remove.
- Grid Supports: Have an interlocking grid-like structure. They are used in situations requiring high strength but have high material consumption and are quite difficult to remove.
Support Settings in Cura and PrusaSlicer
Slicing software like Cura and PrusaSlicer offer various settings to customize support structures. These settings include support density, Z distance, and interface layers.
- Support Density: Determines how dense the support structure will be. Higher density provides more support but increases material consumption and makes removal difficult. Generally, 15-20% density will be sufficient.
- Z Distance: Determines the distance between the support structure and the printed object. A distance that is too close can cause supports to adhere to the object and make removal difficult. A distance that is too far can cause supports to not fulfill their function. Generally, a Z distance of 0.1-0.2 mm is ideal.
- Interface Layers: These are layers added between the support structure and the printed object. These layers prevent supports from adhering to the object, making removal easier. However, they can affect surface quality.
Removing Supports Cleanly
It is important to be careful when removing supports to avoid damaging the printed object. You can remove supports slowly and carefully using a sharp craft knife or pliers. If necessary, you can remove surface imperfections using sandpaper.
Minimizing the Need for Supports
Designing your models to minimize the need for supports reduces material consumption and shortens print time. For example, you can design inclined surfaces with angles less than 45 degrees or support overhanging parts using bridging techniques.
Bridging
Bridging is a technique for creating a surface that hangs in the air between two points. This technique can be successfully applied for short distances without the need for supports. Bridging settings in slicing software...