I’m late to the converstion, but found this when searching for a way to get more “squish” out of my first layer due to uneven fill lines causing tiny gaps in my first layer. This just started when I switched from the factory 0.4mm nozzle to the Bambu 0.2mm nozzle, and it was not a “plug and play” operation as it was on the 0.4mm. In the filament definition alone, I had to change temps upward 15-20C to get enough flow that I wouldn’t stop extruding from slipping/backpressure, and I had to manually adjust the volumetric flow speed and extrusion flow ratio about 20 times before I got the right amount. I had to slow certain areas of printing and adjust initial layer height a few times as well in the Quality page of the slicer.
To answer the original question, which became a holy war of “I must adjust the Z!” versus “You can’t adjust the Z!” - I came from Prusa so of course I was assuming I’d be tossing in some sort of “Live adjust height” Gcode somewhere, but ultimately, I understand the position of “Bambu doesn’t need that.” While technically true, I THINK it’s just because they’re fundamentally doing different things to get the same effect here. Where I had success in the end was adjusting these three values: “Initial Layer Height,” “Line Width → Initial layer,” and “Elephant foot compensation.” Removing the compensation allows more flow on the first layer, as does slightly increasing the line width and slightly decreasing the line height on the first layer.
I hope these tips help you solve your “perfect first layer” issues, fellow makers!
This is where Z-hop / z-hopping can come in. It’s a good function to lookup/look into. Also you could turn on Avoid Crossing Walls, that one usually helps with stringing but also with certain grid infill patterns to keep from ‘slapping’
I also would like to adjust the Z offset and here’s why…
When I run the manual bed tramming GCODE from Bambu Lab to manually level the bed, I have to raise the bed so high to reach the nozzle. The adjustment spindles under the bed are clinging onto the bolts for their dear life. I actually had two of them pop off and the bed come loose during a multi-hour print. I didn’t think to check them because I’ve never had that problem before with any bed-slinger or Core XY printer.
If I could adjust the Z offset and use that as a means to raise the bed so I can screw the spindles on more so they don’t come unscrewed over time due to vibrations from printing would be a lifesaver. The auto bed leveling, which does what it’s supposed to do and does it well, does not address this issue.
Either you are not following the correct tramming procedure, or your Z-belt is badly mis-timed, causing extreme bed tilt.
From the starting position, with all three knobs flush with the bolt ends, tramming should require less than two turns of a knob, and more likely less than one.
The tramming procedure is here:
If your adjustments are still extreme, remove and replace the Z-belt to correct the timing, following the instructions:
You are apparently new to the forum, so I’m assuming you are also new to Bambu printers. Bambu does many things differently than other manufacturers, so while you may know how to tram a printer, you don’t necessarily know how to tram a Bambu printer. Follow the Wiki instructions.
99% of the time, if you think adjusting Z-offset will fix a problem with a Bambu printer, there is another method or setting that will fix the problem without touching Z-offset— that’s why Bambu does not make it easily adjustable. Tramming the bed is not in that other 1%.