changing rotational axis this setup is rotating anticlockwise like a screw  (I've added the keyframes for the rotation) but now, I want to slant this set up a bit (30 degrees) when I do so, keyframed values are not working properly. I tried changing the pivot points and all, but nothing helped me. I did some research on the internet regarding this, but i cannot understand it clearly. I'm a very beginner to blender, please be kind enough to guide me through this. 

-peace-
Create a controlling empty and use as parent.


Create an empty in a useful place.  Perhaps the base.
Parent the components to the empty.  You may choose to not include any object already parented to others. Do this by selecting the children first.  Select the parent last.  


Press Ctrl-p
Select from the pop up menu

Rotate the empty which should rotate all the children in unison.