Multi Jet Fusion (MJF) and Stereolithography (SLA) are two of the most advanced 3D printing technologies — but they serve very different purposes.
- MJF is ideal for producing functional, nylon parts with high strength and production repeatability.
- SLA is the go-to for high-resolution, visually flawless prototypes, typically used for fit checks, cosmetic models, or molds.
This guide compares MJF and SLA in terms of materials, finish, accuracy, cost, and use cases — so you can select the best process for your needs.
🧠 What Is Multi Jet Fusion (MJF)?
MJF is a powder-bed fusion process developed by HP that uses:
- Nylon powder (typically PA11, PA12, or TPU)
- An inkjet printhead to deposit fusing and detailing agents
- An infrared lamp to sinter each layer in one pass
This results in strong, isotropic parts with good accuracy and a matte finish — ideal for end-use components.
💡 What Is Stereolithography (SLA)?
SLA uses a UV laser to cure liquid resin, layer by layer, into a solid part. The resin is held in a vat, and a build platform moves upward or downward depending on the printer design.
SLA produces extremely fine details and smooth, glossy surfaces, but parts are more brittle and UV-sensitive than MJF.
⚖️ MJF vs SLA: Side-by-Side Comparison
Feature | MJF (Multi Jet Fusion)
| SLA (Stereolithography) |
Material Type | Nylon powder (PA11, PA12)
| Photopolymer resin |
Strength | High, isotropic
| Brittle, non-functional |
Surface Finish | Matte, slightly textured
| Smooth, glossy |
Detail Resolution | High
| Extremely high |
Accuracy | ±0.003–0.010 in | ±0.002–0.005 in |
Durability | Production-grade | Cosmetic only (UV-sensitive) |
Support Structures | Not required | Required |
Post-Processing | Minimal | Requires washing, curing, cleanup |
Best For | End-use parts, short-run prod | Visual prototypes, fit models |
🎯 When to Use MJF
Choose MJF if you need:
- Functional, load-bearing parts
- Nylon materials with real-world durability
- Fast turnaround for small-to-mid production runs
- Clean finish and tight tolerances
- Complex geometries without support structure limitations
Ideal for: Housings, clips, brackets, jigs, functional prototypes, robotics, tooling components
🎨 When to Use SLA
Choose SLA if you need:
- A visual model or cosmetic prototype
- High feature detail (e.g., embossed text, sharp corners)
- A mold master for silicone casting
- A fast, affordable way to demo or showcase a concept
Ideal for: Presentation models, dental/medical replicas, jewelry patterns, early design iterations
🔍 Finish & Detail Comparison
Feature | MJF | SLA |
Finish | Matte black or gray | Smooth, glossy |
Feature Sharpness | High | Ultra-high |
Text & Logos | Crisp, readable | Micro-level detail possible |
Paintability | Yes (after priming) | Yes (very receptive) |
Custom Colors | Requires dyeing or coating | Tinted resins available |
🧪 Mechanical Performance
Property | MJF | SLA |
Impact Resistance | High | Low |
Fatigue Strength | High | Very low |
Heat Resistance | Good (PA12/PA11) | Moderate (can warp in heat) |
UV Resistance | Strong | Poor (resins degrade over time) |
💰 Cost Considerations
- SLA is cheaper per part for small visual models.
- MJF becomes more cost-effective for 10+ functional parts, especially when cosmetic finish isn’t the top priority.
Volume (units) | Recommended Process |
1–3 visual models | SLA |
5–500 functional parts | MJF |
500+ units | MJF (with scale pricing) |
🏁 Summary: MJF vs SLA
Use Case | Best Technology |
Functional plastic parts (end-use) | ✅ MJF |
Cosmetic or high-detail prototypes | ✅ SLA |
Snap fits, load-bearing, moving parts | ✅ MJF |
Clear parts | ✅ SLA |
Cost-effective small run production | ✅ MJF |
Display models | ✅ Either |
🏭 Get Expert Help Choosing the Right Process
At RapidMade, we offer both MJF and SLA printing — and we help engineers choose the best solution based on function, finish, speed, and scale.
Want help picking the right process for your part?
Get expert guidance and a custom quote at rapidmade.com
