Elegoo Centauri Carbon Auto Print Clearing (Orcaslicer Print Automation)

Elegoo Centauri Carbon – Auto-Print Clearing Mod - Orcaslicer

This project provides a hardware add-on and custom start/end G-code routines that automate post-print part removal on the Elegoo Centauri Carbon printer.

The included Gcode routines are designed to work with Orcaslicer, just copy and paste the start/end Gcode into their respective locations and hit print! This will cause the printer to print one copy of the part just like normal, and it will attempt to eject the part after completing. It is recommended to try this first with one part before looping/concatenating prints. Stuck parts and crashes can cause wear or damage to the printer, so use at your own risk.

There is currently no provision with the stock firmware on the Centauri Carbon for looping prints (unlike open-source Klipper implementations), the workaround is to simply copy/paste the same G-code into the same file as many times as you want to print. Review the info below for additional details. 

Components

Plate Lifter/Flexer Mechanism
The flexer bar is attached to the bottom of the printer with double-sided VHB tape, and sits directly beneath the front overhanging edge of the flexible build plate (leave about a 4mm gap between the flexer bar and the front inside edge of the printer door frame, see photo). When the Z-axis reaches the bottom of its travel, the build plate contacts the standoff and flexes.
This controlled flex breaks the cured print free of the surface automatically.
Limitations: roughly 50 mm of Z travel is lost, reducing maximum print height to 215 mm (update this in the slicer settings!), and prints should be placed toward the front of the build area for consistent release (also to provide clearance for the printhead at the back of the buildplate for the push-off sequence).

Angled Support Stands
Printed stands tilt the entire printer to about 15 degrees. Tests showed the machine remains stable up to ~20 degrees, so the 15-degree tilt provides a margin of safety while ensuring that gravity helps the released part slide or fall clear of the build plate, reducing the likelihood of jams. Make sure to re-run input shaping with the printer in its new angled orientation with the support stands installed.

Bed Clips

It is necessary to attach the plate to the print bed at the rear to get a good flex on the plate. I used only the rear clips from this project (the front ones would prevent the flexing behavior): https://www.printables.com/model/1409211-elegoo-centauri-bed-lock-clips

All parts were printed in PETG w/ 3 walls and no supports.

Custom G-code Start/End routines
Included start and end routines drive the bed/printhead through the motions needed for automatic print clearing. I've also included my Orcaslicer preset bundle. Use at your own risk.

• The start script is relatively unchanged from stock aside from removing the purge line. Because there is no purge line, it is recommended to add a small brim (~2mm) to your parts to make sure the nozzle is primed.
• The end script lowers the plate to engage the standoff and flex the build surface, then moves the printhead back and forth to push the print out. In the version provided here, the printhead scans across the printbed in steps of about 50mm. It is highly recommended to customize the Gcode depending on the specific parts you intend to automate. Make sure to leave the door to the printer open so the print can be ejected. Or if you want to be fancy you can make a custom door-opener mechanism, but that is out of scope for this project.

The sequences are tuned for medium-to-tall prints; very small or short parts may not release reliably. Monitor the first run carefully—mechanical jams or unexpected part geometry CAN DAMAGE the printer. The files are offered as-is with no guarantees for a particular model or application.

Custom Orcaslicer Printbed Graphic:  

Shows a keep-out zone at the back of the printbed and the area where the flexing occurs for easily identifying ideal print placement. To load the printbed image, open Orcaslicer and go to Printer Settings > Basic Info > Printable Area > Set. When the new window opens click Load > choose the location of your downloaded file > choose the image you want to use > Open > OK. Download the PNG from the images or download the .svg to customize and export as PNG.