Rod Stewart banned a BBC film crew from filming his model railway because it is private despite opening up on screen about his hard-living days and complicated private life.
The 68-year-old singer collaborated with the corporation on a new documentary about his career, called Can't Stop Me Now, which mixes archive footage and interviews with himself and his family.
But he told the Radio Times some things had been off limits - including the railway set at the top of his house.
He said: "There are very few places in my life that I like to keep private: that's one of them, and another is soccer on Sunday morning. We sneak to the location and the team has never given me away. Every three years Model Railroader magazine puts me on their cover, which is better than Rolling Stone."
Rod refused to rule out a reunion with his old band, The Faces, who featured current Rolling Stone Ronnie Wood on guitar.
He said: "Ronnie and I talk about it, and when the Stones finish - Mick Jagger is several years older than me - we'll have a window of opportunity if we're not on zimmers. Keep the faith. I've always looked on myself as one of a band and never sought a solo career."
Rod, who has been married three times, became a grandfather after his daughter, Kimberly, gave birth to Delilah - her daughter with Oscar-winner Benicio del Toro.
The singer praised the actor who he said was 'great and has been generous financially'.
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Patrick McLennan is a London-based journalist and documentary maker who has worked as a writer, sub-editor, digital editor and TV producer in the UK and New Zealand. His CV includes spells as a news producer at the BBC and TVNZ, as well as web editor for Time Inc UK. He has produced TV news and entertainment features on personalities as diverse as Nick Cave, Tom Hardy, Clive James, Jodie Marsh and Kevin Bacon and he co-produced and directed The Ponds, which has screened in UK cinemas, BBC Four and is currently available on Netflix.
An entertainment writer with a diverse taste in TV and film, he lists Seinfeld, The Sopranos, The Chase, The Thick of It and Detectorists among his favourite shows, but steers well clear of most sci-fi.