joints – Limits of FixedJoint in Unity

I’ve built towers of cubes where each cube is connected to the one before with a FixedJoint. At 30 high they flop about as expected, but at a certain point (demonstrated at 100 high) they explode and do something crazy, moving around at light speed.


Is there a limit to the amount of force/torque a FixedJoint can simulate properly? The forces are set to break at infinity.