⚠️ IMPORTANT ADVISORY: This is maintained here purely as a legacy in case this information is needed again in the future. ABL as it exists today is functional. If you are unable to get a good first layer, please refer to the Printer Hardware Pre-Flight Check guide within this wiki and/or reach out in the AnkerMake Community Discord. We will help you figure out the problem or at the very least determine that you may have a mechanical failure that requires an RMA.
You have:
1) Run the auto-leveling routine with filament removed from printer and a clean nozzle.
2) Adjusted the ‘Z-offset’ control.
However, you keep getting a 1st layer that is slightly closer on one side of the bed. If so, this fix might help.
Hopefully, Anker will come out with a fix in firmware in the future. (********!!! THEY HAVE !!!********)
First you can test if this is a problem for you by printing the Full Bed.gcode (/bed-levelling-assets/am5_full_bed.gcode) and you might see something like this, where even though you set the Z-offset correctly on one side, the other side is too high and has small gaps between the printed lines.
https://wiki.printed.boats/bed-levelling-assets/full_bed_result_before.jpg
In this case the left side is too high, or another way of thinking about it is the right side is too close. This modification will lift the right side so it is the same height as the left side. We can adjust the total ‘Z-offset’ down so everything is correct.
When the printer runs the auto-leveling routine it first aligns the Z-axis gantry to be parallel with the print bed. It does this by probing the bed repeatedly on the left and right sides using the nozzle and making small adjustments to the left and right Z-axis motors until it meets the set tolerance. When it is time to print, the alignment is recalled by applying an adjustment offset from the initial ‘home’ position of the Z-axis.
https://wiki.printed.boats/bed-levelling-assets/printer_overview.jpg
The home position of the Z-axis is set independently on the left and right hand side by a ‘sensorless’ homing system that is inside each vertical column. Unfortunately this system appears to be inaccurate. It works as described:
If we cut away one side of the right hand vertical column (the left operates the same way) we can see there is a vertical screw running the length of the column to which the touchscreen (and gantry beam) are attached by a metal block. The metal block houses a nut that travels on the threaded rod, a sliding block that runs inside a groove in the vertical beam and a 'finger' that is highlighted green in the images. When the Z-axis is homed it moves towards the bottom of the printer in the direction of the arrow. The metal finger hits the metal plate highlighted blue. When the finger hits the metal plate the motor current increases due to the resistance and the printer determines this as the home position from which all other motions are calculated.
https://wiki.printed.boats/bed-levelling-assets/printer_side_section.jpg
https://wiki.printed.boats/bed-levelling-assets/printer_right_side_section.jpg
Therefore if we place a thin material such as tape (yellow) under the area where the metal finger (green) touches the base plate (blue) we can change the home position slightly so the desired alignment is achieved. Note that this must be done AFTER the auto-leveling routine or the printer will apply 'correction' for our added material and the result will be null.
https://wiki.printed.boats/bed-levelling-assets/printer_side_section_2.jpg
https://wiki.printed.boats/bed-levelling-assets/tape_on_z.jpg
It can be difficult to place the tape in the correct location as it must be done though the slot in the vertical beam. The use of long tweezers or a flat head screwdriver may help as will shining a flashlight inside the column. The thickness of the added material will depend on the adjustment required. If the adjustment needs more than 2-3 layers of tape (~0.5mm), there is likely a more significant issue with the printer that needs attention first.