Paint and brushes have never been part of David Mach's artistic artillery, and sure enough, when he comes to pick me up at Kirkcaldy train station, there's a yellow hazard jacket stuffed into the back of his car.

"I've been working on a new piece of public art and the metal frame assembly requires heavy lifting and welding gear," he explains as we drive along the coastal road. "I've been doing that in a designer mate's yard in Aberdeen, though it's now in Kirriemuir for the next stage of assembly." Commissioned by Morrison's supermarket for the Esplanade in Kirkcaldy, the abstract piece will be made of driftwood collected from the beaches at Largo and Leven. It's due for completion next month.

"It's f****** huge, 40ft long and very tall. I'm putting it all together with a million nails of copper and steel. I work best to the rythmn of repetitive movement, which makes sense, as I've always been dopey laddie." He calculates the million figure from the fact "you get 200,000 of them in a 40kg box".

If the miner's son and former Turner Prize nominee appears somewhat wired, it turns out he has come from visiting Lesley, his wife of 35 years, in a nearby private care home where she has spent the last two years.

She had a brain tumour removed five years ago in London, aged 52, and though the operation itself was successful, she suffered a series of complications which required further surgery. Mach, who is still based in London but now comes to be with Lesley for two weeks every month, says: "Her original operation in London was very good but the immediate aftercare was terrible. She has undergone 17 operations, a spell in critical care, and a long time in the High Dependency Unit. In Edinburgh, she was in intensive care for three months."

He is critical of the NHS's ability to provide post-emergency care: "You have to

be there every step of the way. God help you if you're in there by yourself with nobody to protect you."

Nevertheless he remains typically upbeat. "Les has difficulty walking and talking and her short-term memory is gone. She is an amazing woman; I've seen her cry only once and only for a few seconds. We're now trying to get her voice back by playing music and encouraging her to sing. I find myself loving being with her."

He has bought a cottage close to the beach in Lower Largo, near his home town of Methil, to facilitate trips home and accommodate visiting family and friends.

He's also working extra hard. It becomes clear his new environment is proving artistically fruitful. He says: "I realise almost everything I've ever done has been inspired by where I come from."

Mach has used matchsticks and pins in previous works, perhaps most effectively in Golgotha, part of Precious Light, his colossal celebration of the 100th anniversary of the King James Bible (now in Gloucester Cathedral). Golgotha featured three massive cast-iron crosses hung with tortured figures covered in thousands of pins made from steel coathangers. He is also fond of the tighter texture of coloured matchheads. Even his 1998 Big Heids on the M8 in Lanarkshire, made of welded steel, can appear like hollow nails.

He stops off to show me the new memorial to the 1st Polish Parachute Brigade in Leven, which he designed partly as a tribute to his own father Josef, a Polish miner who served in the brigade when he arrived in Scotland in 1941 after serving two years in a PoW labour camp in Siberia where he was sent by the Soviet authorities. The brigade was based at Leven and trained at Largo House before being dropped into battle at Arnhem. Unveiled last month, it is made of stone and bronze nails hammered in closely to form a kind of shield or scaly skin. Mach worked on it with his younger brother Robert, who lives nearby, and he is clearly proud of it.

Matchsticks and pins seem to radiate energy. What effect do nails create? "It's interesting, like a great skin or cladding," he says. "In fact, they would make fantastic castle doors."

Like most of his sculptures, the new one for Kirkcaldy requires huge physical effort. Mach, stick-thin himself, thrives on this despite complaining he has "stabbed himself in the foot" by specialising in it. "I play myself out, it's a radical way of making a performance. I can't just spit out my work onto a page. It's my own fault." It means he rarely works alone. For his largest installations he can have a team of up to 30 assistants. He says he's always had a "greed" for materials, and that it's the making of his work that is the best bit for him. "The physical side is really me. I'm driven to make this stuff."

He reckons he's different from other artists, as he doesn't crave solitude and isn't an egomaniac. "I do have massive talent, but I don't go round thinking the world's waiting with baited breath for my next piece. There's a lot of egotism in the art world, and I'm constantly dealing with pretentiousness. I like irritating people by using everyday objects like coathangers, though I suppose that's its own form of pretentiousness."

He's been a Royal Academician since 1998, a privilege he cherishes despite being describing himself as a maverick, as serving on the council gives him influence and access to fellow members such as David Hockney ("a really nice bloke"). He's suspicious of minimalist art because it's "too easy". Growing up in Fife, he was immersed in heavy construction like the colliery shafts, oil rigs and so on. "It was massive, hard stuff. The work ethic seeped in through the soles of your feet, and it was a huge influence on me. I guess that's why I'm suspicious of what I regard as easy work."

He never gets attached to his pieces. "They're not my babies. It's like, 'f*** off, I never want to see you again' once I've delivered it," he laughs. Asked which has been his most affecting, he replies: "My most exciting project is my next one."

That's not to say he isn't absorbed in his metier. "I suffer from feeling over-inspired a lot of the time, but time is the enemy." His restless energy is immediately manifest not only in his roll-up smoking habit but also in the jumble of elegant jars filling his windowsills with green glass fragments, blue-and-white pottery pieces and glazed terracotta tiles, collected on the beaches around Lower Largo. "I'd love to cover the cottage with them. It's a local tradition."

At the moment he's "massively" into collage, revisiting an artform he began as a boy and continued as a student at Duncan of Jordanstone College of Art in Dundee. Working with tiny precision-cut pieces of paper is the antithesis to his giant works. "Small is a joy after the massive, some of which cost £20,000 just to construct," he says.

In the front room are boxes of vintage Commando action comic books, published in Dundee and purchased at a London charity shop. Some of the figures feature in the urgent, energetic collages he has made for the Architecture Meets Art fundraising auction for Enable Scotland, which will also help the Glasgow School of Art Fire Fund. The three works feature the famous Charles Rennie Mackintosh building with smoke billowing out of it and people running in panic.

The figures contain an echo of his father as a young man. In fact Mach is writing a novel based on Josef's life and a draft is with a London publisher. He is also writing poems and short stories, one of which is based on a dish of pickled cabbage his Polish aunt Milka used to make.

"I had a very odd upbringing from very unusual, eccentric, fantastic parents," he says, regaling me with stories about his mother from Maryhill, Glasgow, who sadly never achieved the optimistic outlook his father had, and which Mach himself has inherited.

He drops me back at the train station with just seconds to go. I'm happy to find I'm a tiny bit wired myself.

Architecture Meets Art at the

Italian Centre, Glasgow, October 15-29. Visit