Va tror ni om det här, någon som provat ? Och vad är pva ? ///Kjelle But if u want to blacken the cones wait for a warm day pva(wood working) glue 40% hot water 60 % or 50%-50% will do keep mixing through the process take a cloth a dip it in your water glue mix and go around in circle`s 1 direction till the cone wet,then set it out to dry the theory goes that the cardboard takes on the pvc the water resets the cone and dryes off leaving the cone stiffer i do it ot all my drivers and it makes them look like new and never had a prob no matter how much i crank them morbo!