Selective Laser Sintering (SLS) 3D printers are used in manufacturing and engineering for structure prototyping, small-batch manufacturing, and custom designs. SLS 3D printers can make it easier, faster, and more cost-effective for industries to implement rapid prototyping into their operations.
Of course, this requires using the best SLS 3D printer. SLS 3D printers can vary in the materials they use, build platform size, printer speed, and much more.
This article will explore how SLS 3D printing works, some of the best SLS 3D printers, and what to consider before making a purchasing decision.
Table of Contents
How Does SLS 3D Printing Work?
The SLS 3D printing procedure commences with the development of a computer-aided design (CAD) model representing the intended structure. These CAD models are generated in a 3D modeling software and they represent the object to be produced. Once the CAD is created, it is sliced into a format that a 3D printer can understand and execute.
Inside the printer’s build chamber, a thin layer of polymer powder is evenly distributed on the build platform. The printer proceeds to preheat the powder to a temperature slightly below its melting point. This allows the laser to consume less energy as it moves across the powder, raising its temperature and solidifying it into the desired shape.
The laser scans each cross-section of the CAD model, selectively heating the powder and fusing the particles to form a single layer of the model. After completing a layer, the printer lowers itself by one layer and repeats the process until all the layers are completed.
After the model has cooled down, it can undergo post-processing techniques like cleaning, sanding, and painting to enhance its surface finish, strength, or rigidity.
SLS vs SLA
Stereolithography (SLA) 3D printing is a form of vat photopolymerization: a resin 3D printing technique that makes objects by selectively curing photopolymer liquid resin through light-activated polymerization. With SLA, the build platform is lowered into or raised out of a vat of liquid photopolymer resin during the process.
SLA resins come in various formulations, offering a wide range of properties such as flexibility, transparency, or high heat resistance. This helps SLA technology excel in producing highly detailed, accurate, parts with intricate geometries and a smooth surface finish.
Comparatively, SLS technology is compatible with a broader range of 3D printing materials, including nylon, thermoplastic elastomers, polystyrene, and even metals like aluminum and titanium. The powdered nature of the materials allows for more design flexibility and the production of functional parts with robust mechanical properties.
SLS vs FDM
FDM, also known as fused deposition modeling or fused filament fabrication, uses a heated nozzle to make and deposit melted thermoplastic filament layer by layer until the design is fully created. The plastic or thermoplastic filament is fed through a heated nozzle where it’s melted and then deposited onto the build platform. Once the first layer has cooled, the next layer is deposited. This continues until every layer is complete and the structure is fully formed.
Compared to SLS, FDM prints in a lower resolution–making FDM less desirable for printing intricate designs. FDM also has a tendency for warping, and a slower print time. However, it is also a simpler and more user-friendly option and can be a more affordable process than its SLS counterpart.
SLS vs SLM
Selective laser melting (SLM) uses a high-power-density laser to fully melt and fuse metallic powders to produce a three-dimensional structure. Like SLS printing, the laser is the heat source that melts the powder particles into one whole structure. However, unlike SLS printing where the laser selectively sinters and fuses particles, the laser in SLM systems completely melts entire layers of a part into one homogeneous solid part.
SLM uses metal powders such as titanium, aluminum, or stainless steel alloys to create metal parts. As a result, structures created using SLM printing techniques have higher density and superior mechanical properties.
Compared to SLS printing, SLM printing usually requires extensive post-processing, needs increased material usage due to the need for support during the printing process, and is more expensive.
Best Industrial SLS 3D Printers
With the numerous SLS printers available in the market today, it can be difficult to know which is the best option for your manufacturing and industrial-grade engineering needs. To help, we created this list of the best industrial SLS 3D printers for manufacturing and engineering operations.
1. QLS 820
QLS 820 is a quad laser system offering unprecedented production capabilities designed with automation and scalability. The QLS 820 produces up to 4x the throughput of traditional laser sintering 3D printers and other polymer powder bed technologies. The QLS 820 has smart automation, removing pain points in capacity utilization and downstream labor intensity. It can print up to 8 liters per hour at 20% job density.
QLS 820 has an open-source platform that allows for the printing of many materials, including PA12, PA11, and Polypropylene, as well as aluminum, glass, and fiber-filled options.
Nexa3D QLS820 is trusted by many reputable manufacturers for their production needs. The drone manufacturing company, SmartDrone, used the QLS820 to scale up its production throughput. SmartDrone gained a 60% faster build speed, 2x the packing density, larger build volume, hot-swappable build units, and more.
- Open source platform for plastic, metal, and fiber-filled materials
- High throughput (4x the throughput of traditional SLS printers)
- Smart automation & advanced fleet management software
- 350 x 350 x 400 mm build volume
Best For: High-volume production manufacturing in a variety of materials. Injection mold tolerances for full production capabilities, including high temp thermoplastics like PBT and PA6 materials.
2. QLS 236
QLS 236 is an open platform selective laser sintering 3D printer that offers limitless application options thanks to its compatibility with 16+ qualified materials including a range of Polyamides, PP, PBT, and TPU. Other than these approved materials, the QLS 236 printer is also compatible with patented metal powders from headmade materials®.
QLS 236 offers an unrivaled 21-hour cycle speed using a single 60 Watt CO2 laser and an estimated 22mm per hour build speed. With a 230 x 230 x 250mm build volume, it is perfect for rapid prototyping and the creation of end-use products using a broad range of high-temp thermoplastic materials.
QLS 236 has one of the lowest entry points in the professional selective laser sintering market, combined with lower operating costs due to its powder refresh rate of just 20% and use of third-party materials. It is also compatible with cold metal fusion and can produce titanium and steel parts.
- One of the lowest costs of entry in the SLS printer market
- Cold metal fusion compatible
- 230 x 230 x 250mm build volume
- Open material platform and material versatility (including a range of Polyamides, PP, PBT, TPU, as well as the patented metal powders from head made materials)
- Powered by two advanced intuitive software suites, Buildware, and XYZprint AMsLs
Best For: The QLS 236 printer is a workhorse best for harnessing material flexibility and versatility to create durable structures with robust mechanical and thermal properties. Also perfect for those who prioritize environmental sustainability, and are looking for a printer that can create titanium and steel parts.
3. QLS 230
The QLS 230 printer is one of the most affordable fast-cycle industrial SLS printers in the market today. It offers a swift 24-hour cycle speed using a single 30 Watt CO2 laser to manipulate a broad range of high-temp thermoplastic material into high-quality 3D structures.
The QLS 230’s versatility is notably one of its most important properties. It is compatible with 10+ qualified nylon and metal fusion materials and also works with recycled powders from HP and EOS for ultimate operational sustainability.
In addition to this, the printer’s compatibility with cold metal fusion makes it perfect for a wide range of metallurgical manufacturing processes in the engineering industry, including the creation of titanium and steel parts.
- Lowest cost of entry and low operating costs
- 20% powder refresh rate
- 230 x 230 x 230mm build volume
- Compatible with 10+ qualified nylon and metal fusion materials
- Up to 20mm per hour build speed
- Utilizes recycled powder from HP and EOS
Best For: Companies who look for versatility, swift printing, high-quality structures, and sustainability. They are especially great for creating durable and tough titanium and steel parts.
4. 3D Systems SLS 380
The 3D Systems SLS 380 is a production-grade system that offers high throughput, versatility, and repeatability for manufacturers looking to integrate SLS additive printing in their factory-floor ecosystem. It features a closed-loop process for consistency, a water-cooled laser for thermal uniformity, automated material handling, and a fully automated post-processing workflow.
The SLS 380 printer uses a complementary 3D Sprint software for all editing, printing, and management practices. It is compatible with production-grade nylon materials.
- 2.7 l/hr production speed
- Build envelope capacity 15 x 13 x 18 in (381 x 330 x 460 mm)
Best For: Industrial-scale, process controlled additive manufacturing.
5. HP MJF
HP Multi Jet Fusion is HP’s patented SLS printer. This printer works by depositing fusing and detailing agents in a bed of powder material, then fusing them into a solid layer. The printer distributes more powder on top of the bed, and the process repeats layer by layer. This industrial SLS printer offers high volume and scalability by combining inkjet printing and powder fusion techniques to create high-quality, functional parts. However, it does not offer sustainability as it does not recycle used powders.
- Large build volume
- Material flexibility
- Material reusability
Best For: Building swift and cost-effective intricate 3D designs with high accuracy.
6. EOS Formiga P 110 Velocis
The Formica P 110 Velocis is used to build small to medium-size structures. It is compatible with a wide range of polymer materials, including Polyamides (PA), Thermoplastic Elastomers (TPE) and Polyaryletherketones (PAEK). It has a low running costs that keeps maintenance fees to a minimum and a fast print speed. The Formica P 110 Velocis is a great option for rapid prototyping and the creation of durable end-use products. However, its inability to properly recycle used powder makes it a poor choice for sustainability.
- 200 x 250 x 330 mm build volume
- Build rate of 1.2 l/h with a packing density of 5%
- Approximately 600 kg (1.323 lb)
Best For: Companies that require low processing costs and small-scale production of high-resolution and intricately detailed parts.
7. 3D Systems ProX SLS 6100
The 3D systems ProX SLS 6100 is a large-scale, industry-grade SLS printer suitable for production of tough parts from a wide-range of production or engineering-grade nylon materials. It offers a fast build time, 25% larger build volume capacity, and repeatability (consistently creating identical designs). It comes with a Material Quality Control (MQC) system that enables automated mixing, recycling, and manual-free material transportation to the printer.
- Wide material compatibility
- 381 × 330 × 460 mm build volume
- Automated production capabilities
Best For: Nylon and thermoplastic 3D printing applications.
8. EP-P3850 – Eplus3D
The EP-P3850 Eplus3d is an SLS printer for industrial-grade production and research processes manufactured by Eplus3D, a Chinese company with two facilities in Beijing and Hangzhou. It is suitable for various polymer materials, including PA12, PA12GF, PA11, PA11CF, and TPU. The printer offers a large build size and is a great option for producing functional end-use products in various engineering industries.
- Build volume of 380 x 380 x 500 mm
- Works with a wide range of polyamides
- Detachable forming cylinder
Best For: Producing functional end-use products in various engineering industries.
Best Desktop SLS 3D Printers
Desktop SLS 3D printers allow users to create functional prototypes, complex geometries, and small-scale production parts with high accuracy and durability–right at their desk.
Although there are numerous desktop SLS printers available in the market today, some of the best options include:
1. Fuse 1 Formlabs
The Fuse 1 3D printer offers all the industrial features of a traditional SLS printer but on a smaller, more manageable scale, and with less footprint. It offers a 24-hour cycle speed and compatibility with SLS’s most in-demand industrial-standard powders. It offers swift production, maximum output, and minimum waste, all which are features you can find on many industrial-sized SLD printers.
- Touchscreen display and camera view of printing process
- Wide range of materials
- Build volume 165 x 165 x 300 mm 6.5 x 6.5 x 11.8 in
Best For: Best for manufacturing durable small-batch parts with industry-grade properties.
2. Lisa Pro Sinterit
The Lisa Pro Sinterit is an SLS 3D printer with an open environment and access to a wide range of materials. It offers an open printing system that supports multiple materials -which include multiple PA11 varieties, PA12, PP Polypropylene, and Flexa varieties. The Lisa Pro Sinterit includes 32 open printing parameters and an option to easily change materials.
- Max print volume: PA – 110 x 160 x 230 [mm] (4.3 x 6.3 x 9 [in]) Flexible – 110 x 160 x 245 [mm] (4.3 x 6.3 x 9.6 [in])
- 3 [mm/h] build speed
- Microsoft Windows compatibility
Best For: Prototyping and small-batch production of structures across various industries.
3. Sintratec S2
The Sintratec S2 3D printer is designed with a precise fiber laser and a sophisticated heating system for printing high-quality parts and prototypes. It is dedicated to a range of different materials, including PA12 and TPE, for scalable yet compact SLS printing operations.
- Dimension of 1,490 × 990 × 600 mm
- 10W CW Fiber Laser
Best For: Professional and minimalistic SLS printing operations.
Choose the Best SLS 3D Printer
To enjoy the numerous advantages this additive printing process offers, it is essential to invest in the right SLS 3D printers.
Although every printer on our list offers swift printing speed and high-quality operations, Nexa3D’s range of SLS 3D printers provide unprecedented capabilities, including smarter operations and the fastest print speed in the market today.
Designed with automation and scalability in mind, Nexa3D printers offer high quality, precision, accuracy, and large build volumes to accommodate numerous printing needs.
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