Bingham

These come loose even if screwed on using the screw underneath the joystick as tight as possible. A solution that is neat, clean and simple and non-permanent is to use plumbing tape/teflon tape/thread seal tape. It is cheap and can be purchased from any hardware store. It is used to protect and help bind the thread on connections.

teflon tape

Wrapping this around the joystick does the job very effectively. The balltop stays on securely and won’t budge no matter how much battering. Wrap the plumbing tape around the shaft thread area a few times and then tighten on the balltop.  There is a screw underneath the shaft (see picture) that allows you to safely put counter pressure while screwing in the balltop. You need to undo the 4 screw on the PCB. Be careful - there are 4 washers and screws underneath that can fall out.  

If you don’t have access to the screw underneath to secure while fastening, then use a pair of pliers to hold it. But make sure you don’t scratch the shaft. Put a piece of rubber or something soft around the shaft for protection.

Be extra careful to protect the shaft if securing with pliers

The entire process should only take a few minutes. Good luck!