Print always too tall.. Negative Z offset

  • Im running into issues where my print is always slightly taller then it should be.. I know what your thinking.. check your Steps per mm on your Z.. and i did
    when i move Z it moves the right amount.

    If i print something that is 10mm it will end up being 10.5, if i print something 100mm it will be 100.5
    My extrusion multiplier is good.. other dimensions and holes are accurate.

    My printer is inique in how it homes.. it has a negative Z offset of -1.5mm. when it homes the Nozzle is pushed up and triggers an endstop. this allows me to have no x,Y offset but means a negative value. I also use mesh Grid Compensation. Im wondering if having A negative Z offset and also using mesh grid is causing some bug. which is messing up the height.

  • Moderator

    @adamfilip said in Print always too tall.. Negative Z offset:

    Nozzle is pushed up and triggers an endstop.

    But then it drops back down again when you lift the head again, right?

    How have you measured the trigger height?

  • well the trigger height is my Z offset, it plunges 1.5mm, am i missing something?

  • Moderator

    Yes. The trigger height isn't going to be accurate because the nozzle position changes after it's triggered. It drops back down.

  • it triggers at the same height each time. what makes it not any more or less accurate then having the endstop below the nozzle

  • After calibrating via the unique endstop, G0 Z0 results in nozzle just touching the bed? Passes the paper test?

  • after homing running G0 Z0 its was loose.. i fit 4 sheets of paper. I will adjust by 0.2mm and try again

Log in to reply