I've just had a sweaty one with a rear wheel coming off

When I refitted the wheel I have discovered the thread is worn on the rear stub axle, as I have fitted a new nut but it will not take any torque . Has anyone tried recutting the thread and fitting a slightly smaller corresponding nut?
I've also posted a wanted for a stub axle in the wanted section just incase anyone has a spare they are willing to sell ?(am I right in thinking they are different to 14")