Nexa3D QLS 820

The Nexa3D QLS 820 is an SLS 3D printer from Nexa3D with a 350 x 350 x 400 mm build volume.

Specifications

Technical Specifications: Nexa3D QLS 820

Laser System

Four 100 W CO2 lasers, each with independent control and scanning optics covering four quadrants of the build platform. The combined 400 W laser power and synchronized parallel scanning deliver up to 8 litres per hour: among the highest in the polymer SLS class.

Build Volume and Platform

350 × 350 × 400 mm for a total capacity of ~49 litres. Layer step is adjustable from 50 to 150 µm. Machine weight is 750 kg: reinforced flooring is mandatory.

Thermal Environment.

Calibration

Calibration: Nexa3D QLS 820

• Powder loading and coverage check: via vacuum system; for PA6, limit recycled powder to 60% maximum due to stronger thermal degradation at 240 °C. Expected: uniform, homogeneous layer with no gaps across the 350×350 mm zone.
• Heat-up and thermal stabilization: for PA6 jobs, plan 60–90 minutes to heat the massive machine to 240 °C. Start the lasers only when chamber temperature is stable within ±2 °C of setpoint.

Common defects

Common Defects: Nexa3D QLS 820

Warping in PA6

Edge deformations are more pronounced in PA6 because the operating temperature is close to Tm. Fix: extend preheat, orient parts at maximum angle, reduce cooling rate.

Laser zone mismatch

Visible boundary between four laser zones: caused by mismatched power due to wear or service intervention. Fix: factory laser calibration routine; if >8% asymmetry: service call required.

Orange-peel / porous surfaces.

What it is used for

Applications, Nexa3D QLS 820

Best-fit applications:

• Serial automotive production, 8 L/h throughput and PA6 at 240 °C meet the needs of Tier-1 suppliers for functional heat-resistant components.
• Aerospace prototypes and lightweight structural parts: PP, PBT, and PA11 offer low density and high chemical resistance for aviation interior elements.