Types of 3D Printing

3D printing has become one of the most widely used technologies today. It allows manufacturers to create physical objects directly from digital designs. Instead of cutting the material, 3D printing builds objects layer by layer. However, over the years, different methods of 3D printing have been developed, giving rise to various types of 3D printing.

Each of those types has unique strengths, materials, and uses. Understanding these types is essential if you want to choose the right method for your project and avoid costly mistakes. So, are you new to 3D printing types? Worry not! This detailed article will explore all the major types of 3D printing in simple words. So let’s get started!

3D printing is not a single process. It involves various types; each one differs in the use of 3D printing materials and applications. Having basic know-how of those types is crucial to choosing the right 3D printing method. So let’s dive in and explore the common types with their specifications.

1- Fused Deposition Modeling (FDM)

Fused Deposition Modeling (FDM) is the most popular and widely used type of 3D printing. It’s often the starting point for beginners due to its easy handling. In FDM, the printer uses a plastic filament that comes in the form of a long, thin roll. You have to feed it into the printer, where it gets heated until it becomes soft and semi-liquid.

Then, through a moving nozzle, the melted plastic is carefully deposited layer by layer on the build platform. Once the first layer cools and hardens, the printer adds the next layer on top. This process continues until the final object is complete. The main benefit of FDM is that it can create complex shapes. However, for these shapes, it sometimes requires a support structure.

2- Stereolithography (SLA)

Stereolithography, or SLA, is the oldest 3D printing technology, invented in the 1980s. Even though it’s been around for decades, it’s still very popular due to its high accuracy. Unlike FDM, SLA works with a liquid resin. It uses a printer that contains a container (resin tank or vat) filled with this liquid. A special UV light shines on the liquid, and wherever it touches, the liquid resin becomes hard.

This process repeats layer by layer until the entire model is built. Once the print is done, the object is carefully washed to remove extra resin. In the end, the print is again placed under UV light for final hardening, called curing. This type of 3D printing can create very fine details. However, the resins and the printer itself are costly, making the SLA very costly.

3- Digital Light Processing (DLP)

DLP is somehow similar to SLA because it also uses liquid resin. However, instead of a laser drawing the shape slowly, DLP uses a digital light projector. So how does it work? Actually, inside the printer, there’s a tank of liquid resin. The projector shines light on the resin in the shape of a whole layer at once.

So instead of drawing lines, it flashes the complete design of a layer in one go. When the projector light shines, the resin hardens in that exact shape. The printer then moves up, and the next layer is projected and hardened. In the end, you have to wash off the extra resin to achieve a polished finish. Using this light projector, DLP 3D printing is high-speed and time-saving.

4- Selective Laser Sintering (SLS)

SLS is another popular type of 3D printing that uses powder materials. Those materials can be nylon, plastic, or sometimes metals. In SLS, the printer spreads a thin layer of powder across the build platform. A powerful laser shines on specific parts of that powder and heats it. As a result, the powder particles just melt enough to fuse to form a solid shape.

After one layer is complete, a new layer of powder is spread. The laser repeats the process, and the second layer is completed. Over time, the layers stack to form a complete 3D object. However, unlike many other methods, SLS does not require a separate support structure. Instead, the surrounding unfused powder itself acts as a natural support. This makes it suitable for printing hollow parts.

5- Binder Jetting

Binder jetting is a type of 3D printing that also uses powder material instead of liquid resins. However, those materials primarily include ceramics, sand, or metals. Binder jetting works almost like gluing sand together layer by layer. How? Actually, first, a thin layer of powder is spread on the printer bed. A print head, similar to an inkjet printer, deposits binder droplets onto the powder bed.

However, those droplets drop only where the object needs to form. That part of the powder layer gets stuck together, while the rest stays loose. The printer spreads another layer of powder on top, and the binder sprays again. This continues until the final shape is created. In the end, there remains only loose powder that acts as natural support and is removed.

6- Material Jetting (MJ)

Material Jetting (MJ) is one of the most advanced 3D printing types. It is often compared to a 2D inkjet printer. However, instead of spraying ink on paper, it sprays tiny droplets of liquid. That material is usually a photopolymer resin, which hardens instantly when exposed to UV light. In this type, a printer moves back and forth across the build platform.

It jets microscopic droplets of the liquid material, which allows for very fine details. After each layer of droplets is deposited, UV lamps cure (harden) the resin immediately. This ensures the layer becomes solid before the next one is added. However, due to complex shape creation, this may require added support. Therefore, a secondary material is also jetted alongside the primary material.

7- PolyJet Printing

PolyJet is a 3D printing type that works a bit like an inkjet printer. However, instead of spraying the ink onto the paper, it sprays liquid material. What makes it different from material jetting is the printer used in this type. Actually, it has a printer that has multiple tiny nozzles. It means you can use more than one type of material to build a single 3D product.

Moreover, these nozzles spray very thin layers of liquid resin onto the build platform. As soon as the resin is sprayed, UV lamps inside the printer shine light on it. The light makes the liquid resin instantly solid. This layering process continues until you get the final 3D product. If you are creating overhanging parts, then nozzles also eject a special support material.

8- Laminated Object Manufacturing (LOM)

LOM is one of the lesser-known 3D printing methods, but it is unique. HOW? Instead of using liquid resin, LOM works by stacking thin sheets of material. Actually, first, the sheets of material are cut using a laser or heated blade into slices. These sheets are cut into the shape of each layer of the object. After each cut, the sheet is firmly bonded to the layer below it.

This layering of sheets continues until the final shape product is obtained. One significant benefit of LOM is that it can create large objects at a relatively lower cost than other 3D printing types. Moreover, it is not limited to plastics like PLA vs PETG, like other filament-based 3D printing. Instead, it can use a wide variety of sheet materials, making it versatile for different industries.

9- Directed Energy Deposition (DED)

DED is another advanced type of 3D printing mainly used for metals. Instead of printing an entire object from scratch, DED is often used to repair, add material, or strengthen existing parts. So how does this type work? First, the raw material in the form of powder is supplied directly to the printing area. After that, a laser is focused on a tiny spot of the part.

As the laser hits, it melts both the raw material and a small area of the existing surface. This melted material instantly fuses, layer by layer. As a result, it forms new shapes or repairs damaged ones. What makes this type unique is that it uses a robotic arm that moves the deposition head in many directions. This allows complex repairs and even the creation of large industrial components.

10- Continuous Liquid Interface Production (CLIP)

CLIP is the most modern and fastest 3D printing type of all the above. It is somewhat similar to SLA (stereolithography) because it also uses liquid resin. However, the way CLIP works makes it much faster and smoother than traditional resin printing. The process begins with a container filled with liquid resin.

A special UV light shines through a transparent window at the bottom of that tank. This window allows both UV light and oxygen to pass through. Here, the role of oxygen is critical. It creates a dead zone where the resin does not harden, right above the window. Above the dead zone, the UV light cures (hardens) the resin into the desired shape.

Remember, there’s always a thin layer of liquid resin available and no pause between layers. Hence, the object grows continuously, not layer by layer. Because of this continuous growth, CLIP can produce parts up to 100 times faster than traditional 3D printing. Moreover, the parts are also very smooth, strong, and suitable for industrial use.

How to Choose the Right Type of 3D Printing?

3D Printing has a wide range of types. Choosing the right printing type depends on the requirements of your project. So before you make a final selection, here are the key factors you must take into account.

Material Options: All types of 3D printing support different materials. Hence, you should choose the type based on the material that fits your needs. For example, FDM, SLA, and PolyJet can handle plastics. However, EBM, DED, and SLS are specified for metals. Surface Quality: Different types of 3D printing offer different surface quality. So you should think about how smooth or detailed you want the object to look. For instance, for high detail and smoothness, SLA, DLP, and PolyJet are the best. However, for rough but functional parts, FDM or SLS is good enough. Speed of Printing: Not all types of 3D printing offer the same printing speed. If your business needs to meet strict deadlines, you must not ignore printing speed. So, if you need parts fast, CLIP and DLP are among the quickest. However, if speed doesn’t matter for your project, you can use LOM and binder jetting. Size of the Object: Not all printers can produce objects of the same size. It depends on the design of the model and the type of printing. So if you are making big parts, you should go with FDM and LOM. However, for small and more detailed parts, you can opt for SLA, DLP, and PolyJet. Budget and Cost: Lastly, evaluate your overall project budget. If you are just a beginner, FDM is the most common and cheapest option. SLA, DLP, and PolyJet are more costly because they give better detail. However, Metal printers like CLIP and DED are expensive and used in large industries.

Conclusion

3D printing has completely changed the way we design and create different objects today. From simple projects to advanced industrial products, this technology can handle everything. However, it includes various methods that lead to its types. In this article, I have explored the major types of 3D printing along with their uses.

Each of those types has its own limitations and strengths. That’s why understanding them is essential to choosing the right type for any project. For example, SLA is known for its accuracy, CLIP for its high speed, while SLS offers strength in the products. However, choosing the right type among those depends on the requirements of your business.