Hi folks, I've had my ender 3 v2 for around 2 years and it's been trouble-free until lately. Recently, I've had major issues with the first layer. I found a few worn components, so I got a dual gear extruder and replaced the nozzle, recald the esteps, bed level and z offset. Nothing I do seems to work.
The issue happens on the first layer when it first starts to extrude. The first 5mm or so of extrusion curls up behind the nozzle, then the extrusion sticks to the bed and it continues normally... Until it needs to starts a new extrusion, then the same thing happens...the curl.
I have to think it's something with temperature, but I haven't changed anything about the filament since these issues started.
What print do you use to calibrate the Z distance? Slice a square that's 1 layer thick. The exact thickness (0.2, 0.3, etc) isn't as important. You want 1 layer. If the lines aren't touching, then you're too far. If the lines are touching but you've got ripply texture, too close. If the lines are touching and it's smooth, you're just right. See this for visual examples: https://help.prusa3d.com/article/first-layer-calibration-i3_112364
That's a great article, thanks for the link. I had a suspicion that a ripple texture between lines is an indicator of too low, but it's good to get that affirmation. I usually do a real-time final cal when it's printing the skirt (micro up/down)