In recent years, 3D printing has gained popularity and is becoming increasingly important in many areas. One of the most widespread technologies is FDM 3D printing (Fused Deposition Modeling). But how exactly does FDM 3D printing work? In this article, we take you on a journey through the world of FDM printing and explain step-by-step how everything works.

What is FDM 3D Printing?

FDM stands for Fused Deposition Modeling and is an additive manufacturing technology. In this process, material is applied layer by layer to create a three-dimensional object.

FDM was invented in the late 1980s by Scott Crump and later patented by his company Stratasys. Since then, the technology has developed rapidly and is now indispensable in many areas.

Industrial FDM 3D printing has become a tool for many industries. From prototypes to series production, 3D printing can already produce a range of different plastic products. If you are looking for an experienced 3D printing service provider, we are happy to assist you with our knowledge and our 3D printing farm with over 50 FDM machines. We also offer large format 3D printing service.

 

 3D print farm shelf made of Bambulab P1P FDM 3D printers.

 

Technical Process of FDM 3D Printing

In just five steps, we show you how to get from the idea to the finished FDM 3D print. We work our way step-by-step to the finished printed object! If you are already a 3D printing expert, simply jump to the chapter Applications of FDM 3D printing to learn everything about the advantages and disadvantages of FDM 3D printing.

Step 1: Design of the 3D Printed Object

In the beginning, there was the idea. But what's next? To make your idea for an object usable for 3D printing, you can hardly avoid 3D design. So you need a 3D graphic of your desired object. You can get this in 3 ways.

 

The creation of a 3D model usually happens using 3D design software, such as Autodesk Fusion 360, Blender or Tinkercad. The programs differ due to their functions and are either better suited for industrially precise components (CAD software) or for free forms in design and gaming (Blender). For beginners in 3D design, the Online 3D Design Tool Tinkercad is particularly suitable.

• Scanning using a 3D Scanner

If you already have a physical object that you want to duplicate, you can simply convert it into a 3D model using a 3D scanner. 3D scanners by Revopoint are very affordable and good models for beginners. After the 3D scanning process, you should check your 3D model and manually correct errors in the scanning process using 3D design software.

• Downloading from 3D Model Platforms

If you don't have a talent for 3D design or a 3D scanner, you can also find suitable 3D models on platforms. At Printables, Thingiverse or Cults3D you will find a large selection of different 3D models.

Step 2: Preparation of the 3D Print (Slicing)

Once you have your 3D model as a file, you can move on to slicing. 3D slicer programs convert 3D model files such as .stl, .obj or .stp into the machine-readable .gcode file format. As a 3D printing beginner, it is important to know these file formats and be able to distinguish them.

•  STP

An .stp file (also called .step file) is a standardized file format for exchanging 3D model data between different CAD systems and contains comprehensive information about the model, including geometry and material properties.

• STL

An .stl file is a file format that stores 3D models by describing the surface of an object in the form of triangles and is often used for 3D printing. An .stl file is smaller in size than .stp files, but can only be very limitedly edited using software.

• OBJ

An .obj file is a standardized file format that stores 3D model data and describes geometric information such as points, lines, and faces. It is often used for free forms instead of the .stl file, as it reproduces more accurate object surfaces and is not limited to triangles.

• GCODE

A .gcode file is a text document that contains instructions for CNC machines or 3D printers to control movements, speeds, and temperatures for manufacturing a physical object.

G-Code Generation

G-code is a machine language that controls the printer. It contains information about movements, temperatures, and speeds that are essential for the 3D printer. Before you can start printing, you need to slice your 3D model. Common software is usually provided by your 3D printer manufacturer; popular ones are Prusa Slicer, Bambu Slicer or Orca Slicer. When slicing, the software generates machine-readable code, the so-called GCODE. It contains information about movements, temperatures, and speeds. The created GCODE file is transferred to the 3D printer via USB, WLAN, or the cloud. When slicing, it is crucial to set the correct printing parameters to achieve the desired printing result.

 Cross-section of a 3D printed object with gyroid infill.

• Print Temperature

The correct temperature for the filament is crucial. Too low temperatures lead to poor adhesion, while too high temperatures cause material deformation.

• Print Speed

Print speed affects print quality and print duration. Slow speeds ensure better details, while fast speeds result in shorter print times.

• Layer Height

Layer height determines the detail accuracy and stability of the print. Thinner layers result in finer details, while thicker layers lead to faster prints.

• Support Material

If your object has overhangs, it is advisable to use support material. This supports regions with excessive overhangs, ensuring that no sagging structures occur. Support material must be manually removed after the 3D print is completed.

• Infill

In FDM 3D printing, objects are generally printed with hollow spaces. The reason for this is the line-like extrusion process. With the help of infill, you can set how much infill material should be used in the objects. More infill (40-60%) leads to more stable objects, while a low infill of approx. 15-20% leads to lighter objects.

• Wall Lines

Wall lines can be used to define the wall thickness of objects. This setting can significantly contribute to the stability of 3D printed objects. Even 2 wall lines are sufficient.

Step 3: The Extrusion Process

Once the GCODE file is on the 3D printer, 3D printing can begin. First, the printer calibrates itself, then the heated bed and nozzle of the printer are heated. The print head of the 3D printer melts the filament until it is malleable. Then it is extruded through a nozzle and applied layer by layer to the build platform, at least if you haven't forgotten to load the filament. You should be familiar with the following components of a 3D printer.

 

 

• Print Head and Extruder

The print head is the heart of the printer. It contains the nozzle and the extruder, which feeds the filament.

• Heated Bed and Build Platform

The heated bed ensures that the bottom layer of the print adheres well and does not warp. The build platform is the surface on which the print is created.

• Control Electronics

The electronics control the movements of the print head and the heated bed, as well as the extrusion of the filament. They are the brain of the printer.

Step 4: The Role of Filament

Filament is the raw material used in FDM printing. It usually consists of plastics such as PLA, PETG, or ABS and is supplied on spools. The type and quality of the filament have a great influence on the final result. So don't skimp on the wrong thing!

 

 

• PLA

Polylactide (PLA) is a biodegradable plastic and the most popular material in FDM printing. It is easy to print and ideal for beginners.

• ABS

Acrylonitrile Butadiene Styrene (ABS) is robust and heat-resistant. It is suitable for technical applications but requires a heated build platform.

• PETG

Polyethylene terephthalate glycol (PETG) combines the advantages of PLA and ABS. It is strong, flexible, and easy to print.

• Other 3D Printing Filaments

In addition to the common materials, there are numerous special filaments such as wood, metal, and carbon fiber composites, which offer special properties.

Step 5: Post-processing of 3D Prints

After your 3D printer has finished manufacturing the printed object, you can easily remove your object after the print surface has cooled down. Use spatulas to easily detach your object from the print surface. Wow, your first printed object, congratulations! Small pliers are very suitable for removing support structures. Edges or so-called brims can be easily removed with a deburring tool.

 

• Removing Support Structures

Many prints require support structures that need to be removed after printing. This can be done manually or with special tools.

• Sanding and Smoothing

To achieve a smooth surface, prints can be sanded and smoothed. Sandpaper and chemical smoothing methods such as acetone vapors are suitable for this.

• Painting and Coating

To enhance the print, it can be painted or coated. Special primers and paints ensure a professional finish.

Troubleshooting in FDM Printing

Common problems include poor first layer adhesion, nozzle clogging, and warping of the print.

• Poor Adhesion and Warping

A heated build platform and a good calibration system help prevent adhesion problems. Use special glue sticks to improve the adhesion of difficult-to-print materials.

• Nozzle Clogging

Regular cleaning and maintenance of the printer prevent clogs. Clean the nozzle with a needle or use the "cold-pull method" to clear clogs from the nozzle.

Applications of FDM 3D Printing

• Prototyping

FDM printing in prototyping enables the rapid and cost-effective production of functional prototypes from thermoplastic materials, allowing designers and engineers to test, refine, and validate their designs before mass production.

• Art and Design.

Artists and designers use FDM printing to create complex and unique artworks. Thanks to this new technology, artists can create new objects that were previously impossible to realize with traditional methods.

• Medicine and Research

In medicine and research, FDM printing enables the creation of customized models of bones or organs, which are a valuable aid, especially for preparing complex surgeries.

• Architecture

FDM printing in architecture allows for the cost-effective and precise creation of models and scaled building components from thermoplastic materials, significantly accelerating design and planning processes.

Future of FDM 3D Printing

•  Technological Advancements

Technological advancements in FDM 3D printing include improved print speeds, higher precision, expanded material variety, automatic calibration, integrated error detection, and the development of multi-material and multicolor printing, significantly enhancing the application areas and quality of printed objects.

• Market Trends

The market for FDM printing is constantly growing. Market trends in FDM 3D printing include an increasing demand for personalized products, the integration of 3D printing into industrial manufacturing processes, the proliferation of sustainable and recyclable materials, the development of user-friendly printers for home use, and the growing application in medicine, architecture, and education.

FDM Printing vs. Other 3D Printing Processes

• SLA (Stereolithography)

SLA uses liquid resin and UV light to produce highly detailed prints. SLA is particularly popular for miniature figures due to its high resolution. Disadvantages of SLA include high material and operating costs, limited material variety, longer post-processing times due to required curing and cleaning, potentially hazardous resins, and limitations in the size of printable objects and the durability of printed parts compared to the FDM 3D printing process.

• SLS (Selective Laser Sintering)

SLS uses lasers to fuse layers of powder. It is suitable for robust and functional parts, but it is also costly. The disadvantages of SLS include higher acquisition costs for the printers, longer production times due to the need for cooling phases, rough surfaces of the printed parts that require post-processing, and limitations in material selection compared to other 3D printing technologies like FDM.

• Advantages and Disadvantages of FDM 3D Printing Technology

FDM printing is cost-effective and easy to use but does not offer the highest level of detail. Other processes offer finer details but are more expensive and complex.

Environmental Aspects of FDM 3D Printing

FDM 3D printing has various environmental aspects that need to be considered. On the one hand, biodegradable materials like PLA and recycled filaments can reduce the ecological footprint. On the other hand, 3D printers consume electricity, whose environmental impact can be reduced by using renewable energy sources. Waste is generated from support structures and failed prints, which can be minimized through optimized design and water-soluble materials. Recycling print waste into new filament also helps reduce environmental impact.

 

 

• Recycling of Filaments

Some filaments can be recycled and reused, which reduces environmental impact. Companies like Recycling Fabrik help you recycle your 3D print waste and offer recycled filament for your 3D printing needs.

• Sustainable Materials

There is a growing selection of environmentally friendly filaments that are biodegradable (PLA) or made from recycled materials (rPLA, rPETG).

Tips and Tricks for Beginners

•  Choosing the Right Printer

Beginners should look for user-friendliness and good support. Popular entry-level models include the Prusa i3 MK4 or Bambulab P1S.

• Care and Maintenance

Regular maintenance and cleaning extend the life of the printer and ensure consistent print quality.

FDM 3D Printing: A Versatile Printing Technology

FDM 3D printing is a versatile and accessible technology used in many areas. With the right knowledge and some practice, both beginners and professionals can achieve impressive results.