Mars 4 9K

The Mars 4 9K is an LCD 3D printer from Elegoo with a 143 x 90 x 175 mm build volume.

Specifications

Elegoo Mars 4 9K: Technical Overview

Light Source and LCD Panel

The Mars 4 9K uses a 36-LED COB (Chip-on-Board) array peaking at 405 nm, mounted beneath a 7-inch monochrome LCD panel at 8520×4320 px (9K) resolution. The COB design delivers uniform light intensity across the entire build area without the hot-spot issues common to single-LED arrays.

Optics and Resolution

The pixel pitch of 18×18 µm on both axes is unusually isotropic for this market segment: most competitors have rectangular pixels. This means fine detail is equally sharp regardless of orientation.

Build Platform and Motion.

Calibration

Calibration: Elegoo Mars 4 9K

1. Build Platform Leveling

Before the first print: loosen the platform locking nut, place a sheet of paper on the display, and lower the platform to the Home position. The platform should contact the paper evenly across the whole surface with slight resistance when pulled. Tighten the screws in a cross pattern. Expected result: Even first-layer adhesion across the entire build area.

Tip: Repeat leveling every time you change the platform or FEP.

2.

Common defects

Common Defects, Elegoo Mars 4 9K

LCD-001, Part sticks to FEP

Symptom: The part or supports detach from the build platform and remain stuck to the FEP during lift.

Cause: Insufficient Bottom Exposure Time or poor leveling reduces adhesion to the platform.

Fix: Increase Bottom Exposure by 20–30%; check leveling; clean the platform with IPA; lightly sand the surface for better adhesion.

LCD-002: Suction cupping.

What it is used for

Use Cases, Elegoo Mars 4 9K

Best applications:

Tabletop miniatures, The isotropic 18×18 µm pixels capture sub-0.5 mm details needed for 28–32 mm miniatures in games like Warhammer or D&D. The compact build area is entirely adequate for standard base sizes.