Radcliffe and his co-stars including Emma Watson and Rupert Grint initially shot the scenes which see the characters 19 years in the future at Kings Cross station earlier in the year.
"We are re-shooting some parts of it," the actor told Hit Fix. "It was an interesting one.
"I think we made it very hard on ourselves because we shot it at King's Cross for real. And this time we'll be shooting it at Leavesden on set. To have to rush that sequence, and it's an important sequence, is not something any of us want to do."
He continued: "It's a train station and people actually needed to use that platform. We made it very hard on ourselves and we really want a slightly slower, more measured pace next time."
Watson, who revealed that the reshoot would take place "at Christmas", joked that their time on Potter had still not come to an end.
"It's not over. It's not over yet," she said.
The scenes will feature in the concluding part of Harry Potter And The Deathly Hallows, due to release next July.
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