Fix an object against forces

I have a hand of my player I can position somewhere in the world per drag and drop with a jointy arm on it (the players arm for egoview).
Now, when I have positioned the hand, I want it to be fixed at that location for visual stability (the hand will grab there). But when I turn my player due to looking around, the joints of the arm adds a force to the hand and make it move/wobbling.

I’ve tried to make the hand isKinematic, to freeze it’s position and rotation, iterate the position per script, increase mass and drag, set velocity/angularVelocity to Vector3.zero, lock the rotation per surface normal detection… nothing works.

How can I make it firm as a rock?

Making the hand’s rigid body have isKinematic=true is definitely the correct thing to do, though you may need to set its angular/linear velocity to 0 as well if it’s already gained velocity.

If that’s not working then perhaps something elsewhere in your game is changing its position/velocity/isKinematic setting?