Layer height is the vertical thickness of each deposited layer in FDM or SLA printing — the most impactful single parameter in determining part appearance, print time, and cost. Engineers new to additive manufacturing routinely default to 0.2 mm and move on. At Layer X in Ahmedabad, layer height is selected as part of every job's process specification, because the difference between 0.1 mm and 0.3 mm can mean a 3× cost gap and a visual quality gap that matters in some applications and is irrelevant in others.
FDM Layer Height Options
FDM layer height is constrained by nozzle diameter: maximum layer height should not exceed 80% of nozzle diameter for reliable adhesion. With the standard 0.4 mm nozzle, the practical range is 0.1–0.32 mm.
| Layer height | Print time (relative) | Surface quality | Z-axis strength | Best for |
|---|---|---|---|---|
| 0.1 mm (fine) | 3× | Excellent — near-invisible lines | Highest inter-layer bond | Visible surfaces, master patterns, display models |
| 0.15 mm (standard-fine) | 2× | Very good | Very high | Engineering parts requiring smooth cosmetic surfaces |
| 0.2 mm (standard) | 1× (baseline) | Good — lines visible but acceptable | High | Most engineering prototypes, functional brackets |
| 0.28 mm (draft) | 0.7× | Visible layer lines | Adequate | Concept models, fit checks, large structural parts |
| 0.32 mm (coarse) | 0.6× | Pronounced layer lines | Lower | Large internal structural geometry only |
Variable Layer Height: Best of Both Worlds
Modern slicers (PrusaSlicer, Bambu Studio, SuperSlicer) support adaptive or variable layer height — automatically using fine layers (0.1 mm) on curved and cosmetic surfaces while using coarse layers (0.28–0.32 mm) on vertical walls and internal geometry. The result is near-fine-mode visual quality at roughly 1.3–1.5× standard print time. Layer X applies variable layer height by default on all consumer-facing prototype prints.
SLA Layer Height
SLA layer height is independent of nozzle — it is controlled by the UV laser focal depth. The range is 0.025–0.1 mm. The tradeoff is purely between print time and Z-axis resolution. For most SLA work, 0.05 mm layer height balances resolution and build time.
- 0.025 mm: Dental, jewellery, and microfluidic applications. Near-invisible Z-lines. 4× build time vs 0.1 mm.
- 0.05 mm: Standard engineering/medical resin. Excellent resolution. Recommended default.
- 0.1 mm: Rapid concept models in resin. Acceptable for non-cosmetic prototypes only.
Layer Height and Mechanical Strength
Thinner layers create more inter-layer boundaries — which are the weakest planes in a 3D printed part. However, thinner layers also improve fusion between layers because the melt pool penetrates the previous layer more completely at lower heights. The net effect: parts printed at 0.1 mm have 8–15% higher Z-axis tensile strength than equivalent parts at 0.28 mm, but only 2–4% lower XY strength (more boundaries). For most structural applications this difference is minor; for fatigue-loaded parts the layer height becomes meaningful.
Choosing Layer Height for Your Job
- Concept models, fit checks: 0.28–0.32 mm — fastest, cheapest, sufficient quality
- Functional engineering parts: 0.2 mm — the reliable default
- Consumer product prototypes: 0.15 mm or variable layer height
- Master patterns for moulding: 0.1 mm SLA or FDM
- Dental/jewellery/microfluidics: 0.025–0.05 mm SLA
When you place an order at Layer X, our team selects the optimal layer height for your application as part of the process setup — you specify the outcome quality requirement, we select the parameters. Browse our process options and pricing in the shop.