UnionTech Pilot 250

The UnionTech Pilot 250 is an SLA 3D printer from UnionTech with a 250 x 250 x 250 mm build volume.

Specifications

Laser

355 nm Nd:YVO4 DPSS (diode-pumped solid-state) laser, 800 mW. The 355 nm wavelength (third harmonic) provides superior cure depth control and sharper cure boundaries versus 405 nm desktop lasers.

Optics / Scanner

Dual-axis galvanometer scanner with F-theta lens for distortion correction across the build area. Scan speed up to 12 m/s. Periodic scan field calibration is mandatory to maintain ±0.1% accuracy.

Build Platform

250×250 mm motorised Z-axis platform. Manual dial-indicator levelling. Z travel: 250 mm.

Chamber / Gas

Closed enclosure (active) with UV-protective panels. VOC filtration ventilation. Not an inert-gas atmosphere.

Build Volume

250 × 250 × 250 mm.

Calibration

Platform Levelling

Dial indicator check: planarity <0.05 mm/100 mm. Required after transport.

Scan Field Calibration

Calibration grid print + CMM measurement. Frequency: when deviation >±0.15% or every 6 months.

Jacobs Working Curve

For each new resin: cure depth series → Cd = Dp × ln(E/Ec). Request Dp and Ec from the resin supplier.

Laser Power

Power meter measurement every 3 months. Nominal 800 mW ±5%. M² < 1.3.

Resin Temperature & Viscosity.

Common defects

Geometric Error (Scan Field Distortion)

Cause: galvo scanner drift. Fix: scan field recalibration.

Layer Delamination

Cause: insufficient cure depth overlap. Fix: adjust Jacobs curve parameters; clean vat.

Warping of Flat Parts

Cause: uneven cure shrinkage. Fix: more supports; post-cure jig.

Recoater Streaks

Cause: cold resin or damaged blade. Fix: heat resin to spec; replace recoater blade.

What it is used for

Precision R&D Prototyping

±0.1% accuracy at 50 µm layer height: engineering verification and fit/form/function testing.

Medical Devices

Biocompatible 355 nm resins; anatomical models and surgical planning.

Consumer Electronics

ABS-like/PP-like prototypes with mechanical properties close to production material.

University AM Laboratories.