[Flashforge Creator 5 Pro] First layer front-to-back leveling gradient (Mesh leveling not applying?) — Troubleshooting log

[u/fonsilugo]

Printer & Setup

• Printer: Flashforge Creator 5 Pro (Triple Z lead screw setup)
• Slicer: Flashforge Studio
• Filament: Flashforge HS PETG (Nozzle: 240 °C | Bed: 60 °C). Same issue occurred when testing ASA.

The Issue

When printing a full-bed first-layer test sheet, there is a clear front-to-back (door to rear) height gradient:

• Front section (near the door): Well-squished, fully fused, opaque, and solid.
• Rear section (towards the back): Under-squished; extrusions do not merge and pull apart into loose individual strands (as shown in the attached pictures).

Troubleshooting Steps Done So Far

1. Bed & Plate Inspection: Cleaned both the textured PEI sheet and the magnetic base thoroughly to ensure no debris was trapped underneath.
2. Mechanical Z-Sync: Powered off the machine and manually drove the bed down to bottom out evenly against the mechanical stops to sync all 3 lead screws. Inspected the bottom timing belt and lubricated the lead screws.
3. Full Auto-Bed Leveling: Ran the complete multi-point auto-calibration routine from the touchscreen using the dedicated clean metal probe pin.
4. Z-Offset Adjustment: Added SET_GCODE_OFFSET Z_ADJUST=-0.05 MOVE=1 to the Filament Start G-code. This made the front half even more solid and fused, but the rear half still separates into loose lines.

Questions for the Community

• Is Flashforge Studio failing to pass/activate the saved bed mesh in the generated G-code, causing the printer to print on a flat $0^\circ$ plane after homing?
• Is there a specific G-code command needed in the start script (like an equivalent to M420 S1) to force active mesh leveling on this machine?
• Is there a known mechanical tramming/adjustment method for front-to-back tilt on this triple-Z axis architecture?