hammer does work but really aint the best method, use a proper chainwhip and lock ring tool, like the dura ace one you linked to. really mate dont just use your hands, that willl never really work. if you are not putting the lock ring on tight this can thread the hub, then you is buggered. maybe try putting a decent lock ring on...dura ace campag (this depends on the thread). but remember no more fingers.
hammer does work but really aint the best method, use a proper chainwhip and lock ring tool, like the dura ace one you linked to. really mate dont just use your hands, that willl never really work. if you are not putting the lock ring on tight this can thread the hub, then you is buggered. maybe try putting a decent lock ring on...dura ace campag (this depends on the thread). but remember no more fingers.