Our UPVC kitchen window was always stiff and took quite a yank to close, over time this has weakened the threads in the locking mechanism that the handle screws to. I've re-screwed it time and time again and now the screws no longer bite, the internal thread has all but gone.
How can I re-attach the handle? It is of the type where you depress a button and turn it 90 degrees to unlock and then open the window.
Justin.