{"id":4197,"date":"2025-11-18T14:40:14","date_gmt":"2025-11-18T06:40:14","guid":{"rendered":"https:\/\/chiggofactory.com\/?p=4197"},"modified":"2025-11-18T14:40:21","modified_gmt":"2025-11-18T06:40:21","slug":"what-is-fdm-3d-printing","status":"publish","type":"post","link":"https:\/\/chiggofactory.com\/zh-CN\/what-is-fdm-3d-printing\/","title":{"rendered":"Understanding FDM 3D Printing (Fused Deposition Modeling)"},"content":{"rendered":"\n

What is FDM 3D Printing?<\/h2>\n\n\n\n
\"What-is-Fused-Deposition-Modeling\"<\/figure>\n\n\n\n

Fused Deposition Modeling (FDM) is a material-extrusion 3D printing process . It works by feeding a thermoplastic filament into a heated nozzle, where it melts and is deposited layer by layer along a programmed toolpath to build the part. In essence, an FDM printer works much like a computer-controlled hot glue gun, extruding thin beads of molten plastic that quickly solidify to form a three-dimensional object.<\/p>\n\n\n\n

FDM is the most widely used 3D printing method, particularly at the consumer and educational level. With the largest installed base of printers worldwide, it is often the first process people think of when talking about 3D printing. You may also see the term Fused Filament Fabrication (FFF)<\/strong> used interchangeably. Because \u201cFDM\u201d is a trademark owned by Stratasys, the open-source 3D printing community adopted \u201cFFF\u201d as a neutral alternative; in practice, both terms describe the same extrusion-based process.<\/p>\n\n\n\n

This article explains the basics of FDM, including its pros and cons and the differences between desktop and industrial machines. It also covers the common printing plastics and the situations where FDM is most suitable.<\/p>\n\n\n\n

A Brief History of FDM<\/h2>\n\n\n\n

While FDM is now the most popular 3D printing method, it was not the first to be invented. In fact, it came after both stereolithography (SLA) and selective laser sintering (SLS). Scott Crump filed the first FDM patent in 1989\u2014three years after SLA and one year after SLS\u2014and together with his wife Lisa founded Stratasys to bring the technology to market.<\/p>\n\n\n\n

Throughout the 1990s, Stratasys held the key patents and positioned FDM primarily for industrial prototyping. A major shift came in 2005 with the RepRap (Replicating Rapid Prototyper) Project, an open-source initiative by Adrian Bowyer that aimed to create self-replicating printers. When the core FDM patents expired in 2009, this movement paved the way for companies such as MakerBot, Ultimaker, and Prusa Research to emerge, making desktop printers affordable for hobbyists and educators.<\/p>\n\n\n\n

By the 2010s, industrial systems from Stratasys and consumer printers from companies inspired by the open-source movement together had firmly established FDM as the world\u2019s most widely used 3D printing technology.<\/p>\n\n\n\n

Desktop vs. Industrial FDM Printers<\/h3>\n\n\n\n
\"Industrial_FDM_printers\"<\/figure>\n\n\n\n

Today, this evolution has resulted in two main categories of machines: industrial systems for professional production and desktop printers for consumers and educators. Their key differences are summarized below:<\/p>\n\n\n\n

Property<\/strong><\/strong><\/td>Industrial FDM<\/strong><\/strong><\/td>Desktop FDM<\/strong><\/strong><\/td><\/tr>
Standard accuracy<\/strong><\/td>Around \u00b10.2\u20130.3 mm<\/td>Around \u00b10.2\u20130.5 mm<\/td><\/tr>
Typical layer thickness<\/strong><\/td>0.15\u20130.3 mm<\/td>0.1\u20130.25 mm<\/td><\/tr>
Minimum wall thickness<\/strong><\/td>~1 mm<\/td>~0.8\u20131 mm<\/td><\/tr>
Maximum build volume<\/strong><\/td>Large (e.g., 900 \u00d7 600 \u00d7 900 mm)<\/td>Medium (e.g., 200 \u00d7 200 \u00d7 200 mm)<\/td><\/tr>
Common materials<\/strong><\/td>ABS\/ASA, PC, Nylon, ULTEM<\/td>PLA, ABS, PETG, TPU<\/td><\/tr>
Support materials<\/strong><\/td>Breakaway & soluble<\/td>Same material or soluble (dual-extruder)<\/td><\/tr>
Production capability<\/strong><\/td>Low\u2013medium; repeatable batches<\/td>Low; prototypes and one-offs<\/td><\/tr>
Machine cost<\/strong><\/td>$50,000+<\/td>$500\u2013$5,000<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

How FDM Works: Step-by-Step Process<\/h2>\n\n\n\n
\"FDM_Diagram\"<\/figure>\n\n\n\n

An FDM printer turns a digital design into a physical object through the following steps:<\/p>\n\n\n\n

3D Modeling :<\/strong> The process begins with a digital model, usually created in CAD software or downloaded from a 3D library. The model is exported in a format like STL<\/a> or OBJ, which defines the object\u2019s geometry.<\/p>\n\n\n\n

Slicing: <\/strong>Slicing software converts the 3D model into a stack of two-dimensional layers and generates the toolpaths the printer will follow. It also adds any necessary supports for overhangs and outputs a G-code file containing the print instructions. Key settings,such as layer height, print speed, infill density, and support placement, are chosen at this stage and directly affect print quality and duration.<\/p>\n\n\n\n

Printer Setup: <\/strong>The filament spool is loaded into the extruder, which feeds material toward the hot end. The build plate is cleaned and leveled to ensure proper adhesion of the first layer, and for materials like ABS, it is typically preheated to reduce warping.<\/p>\n\n\n\n

Heating, Extrusion, and Layer Deposition: <\/strong>When the nozzle reaches the target temperature, the extruder pushes filament into the heated head, where it melts. The extrusion head is mounted on a three-axis motion system (X, Y, Z) that guides the nozzle precisely across the build area. As the head moves, it extrudes thin strands of molten plastic onto the build plate along the predetermined path.<\/p>\n\n\n\n

Each new layer is deposited on top of the previous one. The material cools and solidifies quickly; in many cases, cooling fans attached near the extrusion head accelerate this process, especially for materials like PLA. To fill in wider regions, the nozzle makes multiple passes until the layer is complete. Then, either the build platform descends or the extrusion head rises by one layer height, and the machine begins the next layer. This cycle repeats hundreds or thousands of times until the entire part is built.<\/p>\n\n\n\n

The material cools and solidifies almost immediately\u2014often aided by fans for faster cooling with materials like PLA. To fill an area, the nozzle makes multiple passes, much like coloring in a shape with a marker. Once a layer is complete, either the build platform lowers or the extrusion head rises by one layer height, and the process repeats. Layer by layer, the part is built up from the bottom until it is fully formed.<\/p>\n\n\n\n

Support Structures:<\/strong> For overhangs or bridges, the printer generates support material to keep unsupported sections from collapsing. These supports may be printed in the same plastic and later broken off, or in a secondary dissolvable filament if the printer has multiple nozzles.<\/p>\n\n\n\n

Post-Processing: <\/strong>Once the final layer is deposited, the part cools and is removed from the build plate. Most FDM prints require little more than support removal, but additional finishing steps can be applied if a smoother surface or enhanced performance is desired.<\/p>\n\n\n\n

Common post-processing methods for FDM parts include:<\/p>\n\n\n\n