SLS vs MJF 3D Printing: What’s the Difference and Which One Should You Choose?

If you’re looking to print strong, functional plastic parts, two of the most popular industrial 3D printing technologies are SLS (Selective Laser Sintering) and MJF (Multi Jet Fusion). 

At a glance, they might look similar. Both are powder bed fusion processes and often use the same materials like Nylon PA 12. But under the surface, they work in different ways. Those differences can have a big impact on print speed, surface finish, material options, and overall part performance. 

Let’s take a closer look. 

How Are They Similar? 

Both SLS and MJF use a powder-bed fusion process. A thin layer of powder is spread across the print bed, and only the areas that make up the part are fused. The surrounding powder remains loose, providing natural support during printing. 

This approach offers several key advantages over more traditional 3D printing methods like FDM (Fused Deposition Modeling): 

• No support structures required 

• Excellent for complex geometries, including internal channels and overhangs 

• High level of detail and resolution 

• Efficient for batch production, with many parts printed at once in a single build 

  
  

The main difference between the two lies in how they fuse the powder! 

Sinterit Lisa X (Left) representing an SLS machine, HP MJF 5200 (Right) showing a Multi-Jet Fusion machine

SLS: Selective Laser Sintering 

SLS is a well-established technology that uses a high-powered laser to scan and fuse powder particles layer by layer. After each layer is complete, the machine spreads a new layer of powder and continues building the part from the bottom up. 

Strengths of SLS: 

• Handles complex geometries and internal features with ease 

• Compatible with a wide variety of materials, including flexible nylons and composites 

• Proven technology with a long track record in both prototyping and production 

• No support structures needed, allowing efficient use of build volume 

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MJF: Multi Jet Fusion 

MJF, developed by HP, uses inkjet-style heads to deposit fusing and detailing agents onto the powder bed. After these agents are applied, an infrared heating element passes over the surface to fuse the entire layer at once. 

This simultaneous layer fusion makes MJF notably faster than SLS in many applications. It also results in stronger and more consistent parts, especially in the Z-axis. 

Strengths of MJF: 

• Also excels at complex geometries and fine features 

• Faster build times, especially for large batch runs 

• High part-to-part consistency within and across builds 

• Smooth surface finishes and sharp detail resolution 

• High powder reuse rate, which reduces material waste and production cost 

• Improved Z-axis strength, with more uniform mechanical properties in all directions 

  
  

Which One Should You Choose? 

Both technologies can produce strong, high-quality nylon parts suitable for real-world use. The better choice depends on your specific application and priorities. 

Best For	SLS	MJF
Small to medium batches	Yes	Yes
High-detail, high-volume production	Slower	Faster and more consistent
Flexible or specialty materials	More options	More limited
Smooth surface finish and crisp edges	Good	Excellent
Cost efficiency at scale	Moderate powder reuse	Higher powder reuse
Complex geometries	Yes	Yes
Strong Z-axis properties	Moderate	Excellent

In short: 

• Choose SLS if you're working with flexible or composite materials, or need a broader material selection for functional prototyping. 

• Choose MJF if you want fast turnaround, smoother finishes, and strong, consistent mechanical properties in every direction, especially for production parts that will be under load. 

Not Sure Which One to Use? 

Choosing the right technology often comes down to your specific part geometry, surface finish requirements, timeline, and budget. If you're not sure which one fits your needs best, we’re happy to help. 

Send us your part files or reach out with your project goals. We’ll recommend the best process to get the job done right. 

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Tempus 3D is an HP Certified 3D Printing service bureau located in British Columbia, Canada. Tempus offers 3D printing services using HP MJF technology, Sinterit SLS technology, and Formlabs 3D printing technology to offer Nylon PA 12S, TPU, and a wide variety of resins including clear resin in house. Tempus serves clients across Canada and the US, and has next day shipping to most locations in Western Canada and the Pacific Northwest including Alberta, BC, Washington, and Oregon. Serving Vancouver, Calgary, Edmonton, Kelowna, Victoria, Spokane, Seattle, and Portland from its location in Trail, BC.