kuligs2
thanks for reply.
This project is just created, so no code at all.
All I did is on this screenshot, in which I:
1) add two RigidBody, setting one of them static (or adding a StaticBody instead)
2) give them MeshInstance3d and CollisionShape3D
3) assign these RigidBody to a 6DOFJoint
4) turn off the Y in Linear Limit, turn on the Y in Linear Spring
The RigidBody below just keeps falling with no effects from the joint. I tried to mess with some numbers on the right side, still nothing changes.