Going to far up in Y-Axis

When I start a print or hit home on the Z axis. The printer head moves up crashes into the top of the z axis (top of printer) and creates a horrible noise. Any idea how to fix this? Thanks in advance.


John Fitzpatrick

I got an email back from support and they suggested checking the end stop trigger but I can’t seem to locate it. Anyone know where it is?

  • John

This may be it.


It’s a black switch that will bump into the bracket when Z-Home is reached. If that switch isn’t activated, I believe it will continue trying to go to Z-home even though its already at the top. Thus making all those noises you don’t want to hear.

I found this picture on step 4.


Granted I’m only a week into my ownership of the Mini and this is my first 3D printer, so I may be wrong.

Check out step three here:


It is the third switch.

If you are indeed talking about the Z-axis max limit switch and not the y-axis like the thread title, then yes that should be it. Check the wires first to see if a wire came loose out of a connector, then you may try taking off the electronics cover and using a multimeter to ohm out each limit switch wire to make sure there isn’t a break in one of the wires from all the bending they do. If those check out then ohm out the limit switch and see if it’s still good.

Yes, it is the z-axis end stop trigger. It is a millimeter to low. How do I adjust the height so it gets triggered? Thanks for all the help.

Are you sure it is not the right side Z nut being higher and running up and hitting the top brace before the switch on the left is triggered. You should see even spacing at the top position for left and right Z nut to brace spacing.

It could be. I will check it tonight when I get home from work.

It was the z-axis stop trigger. I ended up putting a spacer on the frame so it wouldn’t crash into the top anymore. Thanks again for all of the suggestions.

When you say “top of the printer” are you referring to the top of the frame or the bed? If you’re homing the nozzle, I assume its the top of the bed. To adjust the Z-endstop, there should be a knob the the lower left adjacent to the electronics enclosure. Here’s what it looks like:

If homing the Z causes the toolhead to crash into the frame, then something else is wrong. I believe its controlled by the firmware, but there is an off possiblity that you have the Z inverted in your slicing software… I’ve never tried to invert the axis, but you may want to check. When you home through the LCD, does it move towards the bed?

I have a Lulzbot Mini and added a damper from this post https://forum.lulzbot.com/t/nema-17-motor-vibration-damper-night-and-day/2367/1 which is when the problem started. I stuck a spacer on the top inside of the frame because I couldn’t figure out how to adjust the end stop.