The two fighters needed to be separated by security after the weigh-in.
Wilder, the WBC heavyweight world champion, is set to be ringside on Saturday night and is expected to fight Fury providing he beats Pianeta. Fury is an overwhelming favorite to win his return fight, whereas as Pianeta is not a boxer with any career prospects of note.
So, it could be real or could not be. but one thing's for sure, it's a hell of a lot of fun.
Wilder (40-0, 39 KOs) had only landed in Belfast that afternoon but went straight to Fury's weigh-in at the Europa Hotel.
Fury weighed in at 258lbs, some 18lbs lower than he was for his fight with Sefer Seferi in June.
Tyson Fury responds to taunts from Deontay Wilder. It is likely, however, that Wilder wasn't familiar with the venue, as he shouted his "Bomb Squad" catchphrase repeatedly. Joshua will fight Alexander Povetkin on September 22 at Wembley Stadium, and Wilder could be destined for a fight with Fury later this year.
Of John Fury, he added: "I'll get my grandfather out of the grave to knock him out". The interim WBO featherweight champion Frampton, 31, appeared dry on the scales and after stripping naked came in exactly on the nine-stone limit.
Another wrote: "I hope they make this fight".
It looked for a while like Wilder might finally fight Anthony Joshua (21-0, 20 KOs) in a heavyweight unification bout, but those plans fell through.