Fused Deposition Modelling (FDM) is a favourited 3D printing technology that builds products and prototypes up layer by layer, heating and depositing thermoplastic filament onto the build platform.
Invented by Stratasys more than 30 years ago, FDM 3D printing technology is continuing to be a popular choice amongst modern manufacturers. It allows for greater design flexibility, producing fast and accurate products and prototypes in a much more cost and material effective way, offering a futureproof alternative to traditional production and manufacturing techniques.
The FDM 3D printing process:
STAGE 1: The design
- A designer, engineer, etc. will create a 3D digital model of the desired print using CAD software. The print can be a jig, fixture, prototype, or any other type of object, such as a sculpture, tool, or machine part.
STAGE 2: File preparation
- The digital model is then inputted into GrabCAD software which generates a sliced graphic of the design, establishing the dimensions and features of each layer and setting out the tool path of the print.
STAGE 3: Material preparation
- A thermoplastic filament is loaded into the 3D printer, ready for the print. SYS Systems offers a wide range of Stratasys thermoplastics, elastomer and thermosets from standard to specialty, including; carbon filled, chemical, flame resistant and biocompatible filament.
STAGE 4: Heating and extrusion
- The heating and extrusion stage is a complex process, and there are many factors that can affect the quality of the print. The filament is heated until it reaches a semi-liquid state. The heated material is then extruded through a nozzle (a small opening that determines the height and thickness of the extruded filament) onto the build platform to begin the build. This process is all done with a climate-controlled oven system to guarantee a successful print and the strongest possible bond between printing layers.
STAGE 5: Layer-by-layer deposition
- The extruder moves along the 3D model’s sliced design, depositing the heated material in the pre-determined tool path generated in GrabCAD software. The nozzle moves along the X and Y axes simultaneously, depositing the heated filament onto the selected build sheets on the build platform. As each layer is deposited, it is immediately fused and solidified, bonding to the layer below it. The build platform moves down by one layer height after each layer of filament is deposited, repeating until the entire project is printed.
STAGE 6: Z-axis movement
- The Z-axis stage is calibrated to ensure that the build platform moves precisely. This is important for ensuring that the layers of the print are properly aligned and that the finished product is accurate to the 3D model. After completing a layer, the build platform moves incrementally along the Z-axis (vertically), and the process repeats to build up the object layer by layer.
STAGE 7: Removal of support materials
- The removal of support materials stage of the FDM 3D printing process is the step where the support structures that were used to support overhanging or complex geometries are removed from the finished print. There are two main types of support materials used in FDM 3D printing: Stratasys breakaway materials that break away from the print or soluble supports in which the print is soaked in a heated solution until the support materials have dissolved. Once they have dissolved, the print is removed and rinsed thoroughly with water.
