Ultimaker + z-axis not zero after homing

[ibp1012 0]

Hello,

I posted the following message under the software section a few days ago, however I did not get any help. Hopefully here I will get more responses.

I am new to the 3D print community and have just put together my Ultimaker +, however sadly my prints do not work as I hoped. When I auto home the axis, the x and y components of the head go into the left front corner as supposed to and hit the end switch. After that the plate from the z-axis does the same thing, hits the end switch and is basically set in the right position, ready for printing. However, when I look at my UltiController, the coordinate reading says 0 for x and y, but -49.5 for z. When I hit print, the plate goes down to its relative zero point. This zero point is not 49.5 mm down though, but 141 mm down. Has anyone encountered this problem before?

As a side not, if I home all the axis and turn the printer off and back on, then everything is still homed and my readings are actually all 0. With an SD card I can also get a print going then, without the plate going down 141 mm.

Hope somebody can help.

[SandervG 1,521]

The answer can be found here