He has undergone a seven-and-a-half hour operation to replace his hip, knee and femur.
It was a case of life mirroring art after Star Wars fans saw Darth Vader’s body rebuilt following his duel with Obi-Wan Kenobi.
But the real-life op means 6ft 7ins gentle giant Dave - who was also the Green Cross Code Man - can now walk again, with the aid of a stick.
And the 76-year-old, who also beat prostate cancer two years ago, is determined to keep going to meet the thousands of fans who turn out to see him at conventions around the world.
He will also be signing copies, plus photos and Star Wars memorabilia at Waterstone’s, in Orchard Square, on Saturday from 12noon to 3pm.
In an exclusive chat with The Star’s digital editor Graham Walker he said: “I’m very well indeed. I had a big operation in May. It was an operation on my hip, femur and knee. I had it all replaced.
“But I’m getting over that and I’m mobile again, getting around nicely.
“I’m definitely getting bionic as I get older!” He added: “I’m doing the big Waterstone’s tour, which is every branch in the country. We’ll be bringing photos and other items. Fans can also pay to get their own items signed.”
The book tells Dave’s larger than life story, including how he competed in the Mr Universe contest alongside lifelong friend Arnold Schwarzenegger and trained Christopher Reeve for his role as Superman.
He was the man behind the Darth Vader mask in the first three Star Wars films and his voice was over-dubbed by James Earl-Jones. The two plan to meet up for the first time while the veteran American star is starring in Driving Miss Daisy in the West End.
Dave appeared in many other films, including A Clockwork Orange, but says his greatest job was as the Green Cross Code man during the 1970s. Annual child road injuries and deaths in Great Britain were halved to 20,000 and he got the MBE.
He added: “The kids knew the Green Cross Code Man was Darth Vader. It had such a beneficial effect.”