Rotating object

Hi,

I am trying to rotate a floor, like a trap door. My pivot is at the end of the mesh( Scene component ).

So it is

192616-scene.png

No matter what way i try to rotate it in BP, using Relative / Local or World in the tick I get some strange values.

If I rotate it down it will go from 0 -90 then start at -90 then 0 to 90 then 90 to 0. Also opposite values when I rotate it the other way.

What is the cause of this ?