[Ultimaker2 won't print correctly. Nozzle is too high up]

Or maybe it's not backwards but something is wrong with the Z switch.  With power off pull the bed up and look at the long screw beneath.  Then figure out where the hole is where that screw enters when the bed is down.  Look in that hole - there should be a limit switch in there.  If bits of plastic get in there they can interfere with the process.  Make sure if you push the bed all the way down you hear it click.

What I said above.  That's the issue.  Your bed NEVER goes down.  The arduino thinks it is constantly hitting the Z limit switch.  You got some junk down in there I think.  Clean it out.  Problem solved.

I mean it goes down after hitting the head very hard but that's because it's moving very fast then and the steppers can occasionally go the wrong way if they are being pulsed fast enough and you shove them the wrong way to get going.  So ignore that.  Basically it is SILENT every time it should be going down.

That is exactly what you expect when the limit switch is stuck in the down position.

Thank you so much this fixed it!

[Ultimaker2 won't print correctly. Nozzle is too high up]

Did you change firmware recently?  If so go in there and select "factory reset".  That should fix things.

If you could show a short video of the first few seconds when it moves the bed that would be helpful.  There are several possibilities.

It sounds like maybe your Z axis is moving backwards?  Like it homes up instead of down?  I can't think of anything that would do that other than a broken arduino chip which would require a new board.

Or maybe it's not backwards but something is wrong with the Z switch.  With power off pull the bed up and look at the long screw beneath.  Then figure out where the hole is where that screw enters when the bed is down.  Look in that hole - there should be a limit switch in there.  If bits of plastic get in there they can interfere with the process.  Make sure if you push the bed all the way down you hear it click.

Other things can cause what you describe (you don't describe much so there are lots of possibilities).  In particular if you loaded UM2 extended firmware on a regular UM2.  Or if the microstepping jumper got messed up (it's on the white PCB under the printer in the center of everything).

Show us a video of this slamming you speak of and what happens just before.  That will help a lot with diagnosis.

 

Here's a video:

 

Also when I go into settings and lower the bed it goes up instead.

I fink that the steppers worked correctly until I had to remove the filament tube because of some old filament that was stuck inside so I probably disconnected some wire in the process.

https://imgur.com/aI0Ngww

This is what the wiring on top looks like. Note that the lowermost connector isn't connected to anything.

I tried factory reseting it.

[Ultimaker2 won't print correctly. Nozzle is too high up]

Today I tried to get my Ultimaker2 working and everything seemed fine until I started the printing process. The nozzle is super high up when it prints so everything just becomes a mess.

https://imgur.com/a/MQQRw

I've tried calibrating it as well. Also when the printing starts the bottom "slams" into the nozzle and goes down again.

All help appreciated

/A n00b