Geeetech A20

The Geeetech A20 is an FDM 3D printer from Geeetech with a 255 x 255 x 255 mm build volume.

Specifications

The Geeetech A20 is a mid-sized consumer FDM 3D printer designed as a larger and structurally upgraded successor to the A10. Providing a build volume that expands beyond standard 220 mm cubes, the A20 targets makers seeking a balance between budget and the ability to print larger components. A key design feature is the integration of the electronics and power supply within the sheet-metal base of the printer, which reduces cable clutter and provides a clean footprint.

• Extruder and Hotend Assembly

The printer utilizes a single Bowden extruder mounted to the left vertical frame pillar.

Calibration

To ensure stable print runs and accurate dimensional tolerances with the Geeetech A20, perform the following eight calibration steps:

• Y-Bed Roller Adjustment (Eccentric Nuts)

Due to the larger size (255x255 mm) and weight of the glass bed, the Y-axis experiences high inertial forces during direction changes. If the rollers are loose, the bed will twist, causing layer shifts along the Y-axis.

• Expected result: Smooth travel of the build plate without any lateral or vertical play.

Common defects

The Geeetech A20 shares several common vulnerabilities typical of entry-level printers:

• Hardware defects and mechanical weaknesses
• Cracking Plastic Extruder Tensioner Arm: The plastic arm on the extruder housing frequently cracks near the pivot screw on its underside. This reduces pressure against the drive gear, causing filament slippage and under-extrusion.

What it is used for

Best use-cases

• PLA Hobby Models and Organizers: Excellent for printing medium-sized boxes, cosmetic pieces, and functional prints that fit within the 255x255x255 mm envelope.
• PETG Utility Components: Suitable for printing outdoor brackets, clips, and enclosures where high-temperature enclosures are not required.

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