HI, I have a really long hairline crack in a sculpture that just came out of bisque fire :/ The crack is from the base to the neck, goes all the way through but very thin. Been doing research regarding Bisque fix, Mend it and paper clay. Looking for advise on which is better for hairline as cannot assure product completely fills the middle. Really want to glaze this to cone 6 without it separating even if I have to rebisque.,