Disconnecting Rotates From Rigid Body

[bendingiscool]

Hey, I am having syntax troubles.

Basically I make a cube, make it a rigid body, but now want to disconnect its rotates so I can have them effected by other inputs, so far I have this...

CODE
cube = mc.polyCube()
rigidBody = mc.rigidBody(mass=1, bounciness=0, damping=20, impulse=[0,0,0])
mc.setAttr(rigidBody + '.allowDisconnection', 1)

#### problem here:
mc.disconnectAttr('%s.sz' % cube,'%s.impulseZ' % rb)
####

but am now unsure of the disconnectAttr syntax when its between the variables of a rigid body and it's parent.

Thanks, Chris

[kurianos3d]

CODE
mc.disconnectAttr('%s.sz' % cube[0],'%s.impulseZ' % rigidBody )

i dont know i am right