Z probing and Material height etc

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This topic contains 5 replies, has 4 voices, and was last updated by  jimboh 3 days, 6 hours ago.

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  • #96899

    jimboh
    Participant

    I have my MPCNC printing crowns great. Have dual endstops and I have been manually moving pen to material surface lowering pen to touch and then resetting the mpcnc. In my gcode I then do:

    G90
    G92 Z0
    G00 Z2.0000 F480
    G28 X Y
    G0 X100 Y100 F10000
    G92 X0 Y0

    So my pen is within the printing area and z0 is set and the frame is nicely squared thanks to dual endstops.

    Reading the “Basic” instructions…

    When Zprobe is used the guide shows homing as G28 x y z which is off material. Whereas I assume from what I have read I need to zprobe on my workspace?

    So what method do most people use (who also use endstops) to get X, Y and Z in the correct position to start cutting/drawing?

    If you disable steppers and move z and y to a reference point does it still know where it is (x/y coordinates) when steppers are re-enabled?  – I am thinking home to square frame, turn off steppers, M0 to pause, move to correct point, resume, z probe and then G92. Does that sound right (guess I should try). Interested in other methods though.

    Also, anybod zprobing when not using a metallic cutter. eg plotting with a pen? What are you using as a probe?

    • This topic was modified 1 week, 1 day ago by  jimboh.
    • This topic was modified 1 week, 1 day ago by  jimboh.
    • This topic was modified 1 week, 1 day ago by  jimboh.
    #97024

    Aaryn
    Participant

    If you disable steppers and move z and y to a reference point does it still know where it is (x/y coordinates) when steppers are re-enabled?  – I am thinking home to square frame, turn off steppers, M0 to pause, move to correct point, resume, z probe and then G92. Does that sound right (guess I should try). Interested in other methods though.

    If you disable the Steppers then no the machine will have no idea where it is.  You would need to do something like this.

    • Manually Home X and Y from the LCD or Repetier. (So it is square)
    • Use the controls to move the machine to your reference point from LCD or Repetier (So it is over your material)
    • Home Z (with probe)
    • Use G92 X0 Y0 Z(probeThickness)  to make the machine thing that 0,0,0 is the very top of your work piece.  This can be done as part of the Starting gCode.

    To do some of these steps from the LCD you have to have the individual homing options enabled in the firmware.

    #97057

    Jamie
    Participant

    Also if you disable steppers the machine might not hold itself square.  Another reason to do as Aaryn describes.

    #97223

    jimboh
    Participant

    Ah, thanks Aaryn. That is what I feared regarding disabling steppers.

    I suppose I could use center of the bed as 0,0,0 and make sure the material was always positioned over the center. I could then do in gcode –  Home, Raise Z to max, move to center, Z probe and g92 X0 Y0 and Z(probe).

    I could  then set up fusion 360 so that 0,0,0 is always in the center of my bed (I am new toFusion and can’t remember the correct terminology).

    Unfortunately the LCD is not the friendliest interface for maneuvering the gantry around. It would be nice to have alternative controls at the machine. Perhaps I will have to investigate  a joystick controller I seem to recall seeing discussed on this forum.

    I do have spare laptops & tablets so  I could use SW. I am happy using Octoprint with my 3D printer with a pi,  I also have a smaller printer with Octoprint running on a w10 laptop. I stopped using Pronterface because it did not seem to have a stop print function??  Have not tried repetier yet, and only dabbled with Estlcam control. Trouble is my workshop is  a very dusty place for a laptop.

     

    #97354

    Ryan
    Keymaster

    Trouble is my workshop is a very dusty place for a laptop

    Slap a pi on there, use Jeff’s V1Pi, and control with your phone. It is by far the easiest way to get better control, adding joysticks and extra hardware can not compare to a cellphone connected wireless.

    #97509

    jimboh
    Participant

    Slap a pi on there, use Jeff’s V1Pi

    The pi I have on my Cubex Duo reprap conversion has Jeff’s V1Pi on it and a webcam. Neither are bolted down so I could share it between both, Unlikely I will need to use both at the same time. Yes you are right, it is a great way to control. Just struggle a bit with touchscreens and  big fat (and )dirty fingers lol.

    • This reply was modified 3 days, 6 hours ago by  jimboh.
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