When printing on my Ender 3 Max Neo (stock except for a PEI bed), the right side of the bed is always printing too close. I manually leveled the bed, and then I run the auto-leveling sequence. I also have it set to run auto-level before every print, and confirmed that it’s enabled using M420 S1 after the G29 in the opening gcode.
I also disabled it in one test with M420 S0 and confirmed that it is making a difference so it appears to be working, but the auto-level map seems to be incorrect every time. Any ideas?
You get different map every time? Maybe your sensor is not trigering consistently? Is it wobbly? Hopefully its the sensor issue, otherwise its probably hardware issue (X Gantry or bed).
the right side of the bed is always printing too close
If the height diffetrence is always the same, you can try manual bed mesh leveling (sensor not even required). Create one map and load it every time. You can also just eddit existing map if you know what is wrong.
I did some research and was able to pull the mesh. I put it into a visualizer and found that the right side is definitely incorrect (as it matches with the “too low” behavior that I’m seeing. I tried to copy the image here, but Sync won’t let me, but here’s the values.
0 1 2 3 4 5 6 7 8 9 10 11 12 0 +0.03500 -0.02855 -0.09156 -0.15566 -0.22250 -0.29867 -0.38125 -0.45758 -0.51500 -0.54590 -0.55844 -0.56363 -0.57250 1 +0.01869 -0.01856 -0.05355 -0.09305 -0.14383 -0.21602 -0.30324 -0.38746 -0.45064 -0.48415 -0.49888 -0.50610 -0.51707 2 +0.00234 -0.00695 -0.01215 -0.02553 -0.05938 -0.12765 -0.22023 -0.31329 -0.38297 -0.41951 -0.43676 -0.44629 -0.45969 3 -0.01393 +0.00144 +0.02248 +0.03217 +0.01352 -0.05072 -0.14723 -0.24723 -0.32193 -0.36066 -0.37977 -0.39103 -0.40621 4 -0.03000 +0.00178 +0.04016 +0.06533 +0.05750 -0.00240 -0.09922 -0.20143 -0.27750 -0.31633 -0.33563 -0.34711 -0.36250 5 -0.04428 -0.00747 +0.03596 +0.06615 +0.06324 +0.00837 -0.08337 -0.18082 -0.25285 -0.28864 -0.30564 -0.31512 -0.32836 6 -0.05734 -0.02364 +0.01604 +0.04376 +0.04156 -0.00781 -0.09062 -0.17835 -0.24250 -0.27303 -0.28596 -0.29184 -0.30125 7 -0.07236 -0.04528 -0.01310 +0.00888 +0.00535 -0.03877 -0.11166 -0.18823 -0.24340 -0.26810 -0.27650 -0.27838 -0.28352 8 -0.09250 -0.07094 -0.04500 -0.02781 -0.03250 -0.07238 -0.13719 -0.20465 -0.25250 -0.27246 -0.27719 -0.27582 -0.27750 9 -0.11980 -0.10205 -0.08041 -0.06654 -0.07207 -0.10913 -0.16849 -0.22982 -0.27275 -0.28955 -0.29183 -0.28831 -0.28770 10 -0.15219 -0.13878 -0.12196 -0.11197 -0.11906 -0.15424 -0.20929 -0.26559 -0.30453 -0.31884 -0.31920 -0.31399 -0.31156 11 -0.18660 -0.17777 -0.16597 -0.16010 -0.16902 -0.20270 -0.25387 -0.30559 -0.34092 -0.35300 -0.35165 -0.34493 -0.34090 12 -0.22000 -0.21563 -0.20875 -0.20688 -0.21750 -0.24949 -0.29656 -0.34348 -0.37500 -0.38473 -0.38156 -0.37324 -0.36750I see the mesh, but cant tell what is wrong with it. Is your mesh about the same every time after running ABL? If you check any point on the right side, do you think your bed and nozzle are at the same distance after every ABL run, but sensor reading is wrong on that side?
Basically you have to identify is your sensor faulty, otherwise your bed or X gantry might be moving in Z over time. Faulty sensor can be fixed or replaced or just go to manual mesh leveling.
I would try probing the same point multiple times in a row and see what difference you see in readings. You could also do a manual mesh and compare it with auto bed mesh.
Move nozzle close to the bed, disable XY motors and move nozzle around while observing the gap. 0.1 mm variation can be seen by naked eye (alternative to paper method) and you have 0.6 mm according to your mesh.
Use a metal ruler (or something flat) and a light to confirm how much and where is bed bent, again visual inspection.
The mesh ends up being pretty similar every time, showing that the right side of the bed is lower than the left. The concern is that, when printing after auto leveling, the nozzle is far too close on the right side, causing first layer issues, but all is well on the left. It’s almost like the printer believes that the nozzle is further from the bed than it actually is, but only on one side.
I found that the bolts holding the gantry to the base had come loose slightly, and tightened them. That seemed to help a bit, but the issue is still there. I was going to try leveling the x gantry, but I’m still trying to figure out how to do so.
How do you edit, or even view, the map that’s built?
What kind of probe? Are you preheating before auto levelling? Have you manually calibrated an offset? I used a sheet of paper which was good enough to rough it in and then fine tuned from there. Have you followed marlin’s bed levelling steps?
G29 S0should return mesh results, plonk the reaults of that into a visualisation tool of your choice if you don’t have the ability to visualise with your printer interface (klipper does and if I recall so does octoprint) to help see if you need further adjustment. Definitely do your mesh levelling at your expected print temperatures, give it a good heat soak of like at least 15 minutes before testing, preferably longer but good enough is usually fine.How did you manually level? I ended up doing a silicone tube mod on my prusa to get the build plate as level as possible,
now within ~0.1mm deviation over the build plate at 90c which is definitely good enough for me. I also moved from a pinda probe to a tap probe, induction probes are definitely fine imo, you just need to tune the offsetThe bed leveling is done with the bed and nozzle preheated to printing temp. As for the probe, it’s the stock probe on the Ender 3 Max Neo.
The interesting part is the heat soak. I typically heat it and then only wait a minute or two. I’ll let it sit for a while and try again.
To be fair, I only find it needed on stuff above pla, and even then it’s often good enough to preheat first, changed my start gcodes around to preheat before mesh levelling.
Not sure if creality has a macro to calibrate the z axis, totally possible there’s a bit of skew across the x gantry, running the z axis just past its max usually sorts it on my franken-prusa, trying to adjust bed levelling with skew is a mess and made it look like the entire bed was going downhill.
I’ve got a long shot, but I saw a similar post a while back where someone was having extrusion issues on specific parts of the bed. After everyone was digging through diagnosing the gcode, extruder, hotend etc, ended up that the bowden tube was getting bent/stuck at certain positions and was keeping the filament from flowing properly.
IIRC, your printers cables running to the nozzle come from the left side… are they maybe getting caught on something as the nozzle moves to the right? Or anything else that could cause your print head/ sensor to get pulled or pushed while on that side of the printer?
I saw in a comment you’d mentioned some bolts had come loose - check the bolts holding your z-axes bolts and make sure they aren’t loose too. Have you tried calibrating bed tilt? (I don’t have dual z so don’t know much about this but do know it’s a potential problem)
Hope you get it figured out!