Rigidbodies giving trouble

I’m a noob to Rigidbodies, so this exercise is just a simple test, but I can’t get it to work as I want.

I’ve ‘hung’ a series of balls from ‘cables’ with hinge joints. I want to lift up the first ball and for it to knock the second, third and so on, so that the last ball swings on out and then back again. Most people have seen these office stress busters (or inducers!).

But I’m having trouble restriciting the direction that the ball and cables can be rotated. I’m not sure what objects I should be setting up Constraints on. Also the cables seem to detach from the balls.

Any help would be greatly appreciated?

You’ll probably find that the configurable joint works better for this kind of thing than the hinge joint. You can set the X/Y/Z motion constraints to Locked (as appropriate) to confine the balls to a single plane while still allowing rotation around the hinge point.