MJF vs SLS 3D Printing: When to Use Which
Choose MJF (Multi Jet Fusion) for production parts and faster lead times — better surface finish and 30–50% cheaper at volume. Choose SLS (Selective Laser Sintering) for one-off prototypes, parts requiring colored dyeing, or geometries with very thin walls below 0.7mm.
MJF and SLS both produce strong nylon parts from powder beds, but their economics and finishes diverge sharply. The right choice depends on volume, finish requirements, and turnaround.
How They Differ Technically
- **SLS** uses a CO₂ laser to selectively sinter nylon powder layer by layer. Mature technology since the 1990s. - **MJF** (HP) uses inkjet heads to deposit a fusing agent on powder, then fuses an entire layer with infrared lamps. Newer (2016+), 10× faster build rate.
Cost & Lead Time
For batches of 10+ parts, MJF is typically 30–50% cheaper than SLS due to faster build cycles. For single prototypes, SLS and MJF cost roughly the same. Lead time at FormHub: MJF 3–5 business days, SLS 5–7 business days.
MJF vs SLS Comparison
| Property | MJF | SLS |
|---|---|---|
| Material (most common) | PA12, PA12-GB | PA12, PA11, PA12-GF |
| Tensile strength | 48 MPa | 50 MPa |
| Surface finish | Smoother (grey) | Slightly rougher (white) |
| Min wall thickness | 1.0 mm | 0.7 mm |
| Best for color | Limited (grey) | Excellent (dye-able) |
| Cost (10+ parts) | 1.0× | 1.4× |
| Lead time | 3–5 days | 5–7 days |
| Production volume sweet spot | 50–10,000 | 1–500 |
Frequently asked questions
- Are MJF parts as strong as SLS parts?
- Yes — within 5%. Both produce isotropic nylon parts with tensile strength around 48–50 MPa and elongation at break of 15–20%.
- Can MJF parts be dyed?
- MJF parts are inherently dark grey due to the fusing agent. They can be black-dyed for cosmetic uniformity but cannot achieve bright colors like dyed SLS parts.
- What is the minimum wall thickness?
- MJF: 1.0mm minimum (0.7mm possible with risk). SLS: 0.7mm minimum reliably. For very thin features, SLS is the safer choice.
- Which is better for production runs?
- MJF wins for production runs of 50–10,000 parts due to faster build rate and lower per-part cost. SLS remains preferred for low-volume custom prototypes.