Town hall chiefs had to bring in an outside firm to put things right after trusting volunteers to overhaul the Mirror Ball.
The artwork has been reinstalled on the Prom in South Shore after being taken down for an £80,000 revamp last November.
But it was months behind schedule – with the council initially saying it would be back up for the busy summer season.
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Andy Farrell from Thornton firm Mirror Finish NW said his team was drafted in just 10 weeks ago to completely re-tile the spinning ball.
“The council asked us to come and have a look because they were having a few issues,” he said. “We hacked off everything that was on there already.”
Students from Blackpool and The Fylde College had been tasked with replacing some of the 47,000 tiles.
When asked about their work, Andy said: “Obviously there aren’t many people who have tiled mirror balls before, especially not at this scale.”
Andrew Walker from the college said he was aware tiles had to be replaced, but that the work had been "signed off" before leaving the college by a project lead - while a council spokesman said of the students: “They were learning a new skill to give them hands-on experience.
“Unfortunately lockdown impacted on the time the students were able to spend on the project, and Mirror Tiles NW continued the project.”
Coun Tony Williams, leader of the opposition at the town hall, said it was “unfair” of the council to put so much responsibility on the shoulders of students.
He said: “We can’t criticise the college. It’s great the college took this challenge on but the council really should have supervised the work and brought in experts who could have project managed the whole thing.”
The council spokesman added: “The project has been a team effort with different parties playing their part.
“The students were learning a new skill to give them practice experience. We were delighted by their efforts, enthusiasm, and their work with other team members.”