Irate coaches demanded the scales be checked after some boxers tried to sweat off weight by using saunas or going for runs only to return and weigh more than before.
"It is a farce, but there is not a lot more we can do, I have never seen this before," Australia's assistant boxing coach Don Abnett told Australian Associated Press.
Northern Ireland coach Stephen Friel added that the incident was unprecedented. "The whole place was in uproar," said Friel. "All of the coaches here said they had never seen anything like it."
Competition manager Lenni Gama initially tried to brush the issue under the carpet, saying: "The scales are perfect".
But Gama eventually relented and the weigh-in was postponed to Tuesday morning, just ahead of the opening bouts. The scales will be recalibrated.