Adjusting the Z 0 height

Discussion in 'Getting Started' started by Andy Cohen, Oct 4, 2019.

  1. Andy Cohen

    Andy Cohen Well-Known Member

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    I already adjusted per the method in the Guide, but it's not as close as I would like it.
    Is it best to adjust the overall bed distance using each tool's offset? The way I did it on my other Duet machine does not seem to apply to the TC since the method required measuring the hotend tip distance from the bed. Perhaps if I picked up T0 then set the bed to home then measure with something that I slip between the nozzle and the bed?
     
  2. Greg Holloway

    Greg Holloway Administrator
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    To get the bed offset I pick up a tool and move it over the bed to X0 Y0 and then adjust the bed up/down until it is just touching the glass and then use the vale as an offset. You can get surprisingly good results.
     
  3. Andy Cohen

    Andy Cohen Well-Known Member

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    Use the value as an offset where exactly? There are so many places where things can get redundant.

    I assume it's the G10 lines at the end of the config file, but my assumptions have been wrong before.
    It did work though!
     
    #3 Andy Cohen, Oct 6, 2019
    Last edited: Oct 6, 2019
  4. mhe

    mhe Well-Known Member

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    It is the G10 line. I just made a square with 0.2 layer thickness. Adjusted it first with baby steps and slowly dialled it in with a few iterations. Now got it to where I can do a single layer to 2/100 of a mm exact, which is way more than good enough. Takes quite a bit longer than the procedure outlined in the calibration part of the documentation, but the results speak for themselves.
     
  5. Greg Holloway

    Greg Holloway Administrator
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    Yes, the G10s in teh config file. those are the only offsets that should be adjsuted. thre shouldnt be any anywhere else.
     
  6. mhe

    mhe Well-Known Member

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    Also, if you start with the E3D github config, there are TWO blocks of G10s: the first one resets the offsets to start with a clean slate, leave these alone. And then there is a second block, consisting of just 4 lines. These are the ones to adjust. If you adjust the upper ones, then nothing will change as they get overridden by the lower ones, don't ask me how I know... ;)
     
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  7. Andy Cohen

    Andy Cohen Well-Known Member

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    So if the number for the Z axis offset goes further less then zero is that add more distance between the nozzle and bed or less???
     
  8. Nibbels

    Nibbels Well-Known Member

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    I have a short path Hemera: Z-5.28
    I have a TitanAero where the nozzle tip is lower: Z-7.75
    And a vulcano would have more minus.

    I always think that I adjust the bed, not the nozzle. That makes it easier for me to understand.
    Does this help?

    I adjusted my nozzles two days ago. I used a cheap usb microscope for it and had the maximum focus set. Then I drove the nozzles to the point where they looked the shapest. I guess that I now have +-0.02. But I will probably add a switch to my bed which can equalize all my tools nozzles faster.
     
  9. Spoon Unit

    Spoon Unit Well-Known Member

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    I use a slightly different method for Z alignment. I pick up the Tool, move it to the center, adjust Z with the dashboard or G1 H1 moves if I can't move low enough. Once I have the bed just right according to my eye, I then issue G10 commands until the dashboard reflects exactly what I'm seeing. Once I have Z0 shown in the dashboard, the last G10 command issued is the one I place in config.g.
     
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  10. Nibbels

    Nibbels Well-Known Member

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    Your method is better than my microscope tuning.

    I today tested the microscope tuned offsets and kind of failed. It first looked awsome and logical but it was more like +-0.02..0.03 nozzle to nozzle and that turned out to be unusable.
    Next I try to install some flat micro switch attached to the bed. Only to equalize nozzles. Babystepping is another last tune then.
     
  11. Andy Cohen

    Andy Cohen Well-Known Member

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    Yes thanks. About to switch all the E3d V6 nozzles to the Micro-swiss with the longer, more conical tip.
     

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