Linking and a minor problem.

While I was examining procedures of adding bones to mechanoids. I saw a video were bone parts were linked to each other insted of "attach bones". Then it hit me, that I could do the dreadnought claw animation by simply linking, no need for bones.
I went to my scene and linked the claws to the rotating part of the arm, then rotated the arm to be in the angle I wanted. This is when problems occured. While the arm was in the upright positiom the rotating part of the arm would rotate around the axis I wanted, when I repositioned the arm it would seem it spined on a diffrent axis.
So I selected the pivot point at  tryed repositioning it by hand and by "center to object" align to object" "align to world" with no effect, I must have spent 2-3 hours to fix it. It took so long that my computer needed restarting.
After the restard it seemed to behave normaly as expected and rotated perfectly in an angle.

So I did some animation of the rotating piece.

This first piece was my first attempt with bones on 2 basic shapes, notice how the long part twists when I roatated the bone. Not an effect desired when animating mechanical parts. Apologies sor the small sequences.

* At a previous post "Group,attach or boolean?" I sujested attach for animation completly forgeting about link. So I attached the claws to the rotatting part. What I did not take in mind is that when attached you can't not alter the pivot point even in element mode. Here is a render of it anyway.

The video bellow is a rendering on the upright position with link showing the claws and the rotators work fine.
this is in the upright position after this i spent half my day trying to figure why it would act the same when the arm was in a diffrent angle.

And my working video of the first scene (with the arm at an angle) working on the rotator.