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?

  • morbidcactus@lemmy.caEnglish
    0·
    6 months ago

    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 S0 should 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 offset

    • pepsison52895@lemmy.oneOPEnglish
      0·
      6 months ago

      The 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.

  • rambos@lemm.eeEnglish
    0·
    6 months ago

    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.

    • pepsison52895@lemmy.oneOPEnglish
      0·
      6 months ago

      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 -0.36750
      • rambos@lemm.eeEnglish
        0·
        6 months ago

        I 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.