IK rig spins out of control I'm following a tutorial on youtube about IK rigging. So far I've set up an FK rig and am creating an IK rig. I have put an IK constraint on the left upper arm and the left forearm. But if I try to move the left hand, the whole arm goes crazy. It doesn't follow the hand like a proper IK rig should. And the movement seems random to me.

I use Blender 2.71

Blend file: https://dl.dropboxusercontent.com/u/61219663/Character_Rig_01.blend

Images of Rig:




Images of rig going crazy:
Found the solution:
You need to clear the parent of the hand_IK.L
So hand_IK.L needs to be a separate object from the rest of the chain.

Go into edit mode, select hand_IK.L and press ALT + P. Choose "Clear parent".