THE American poet Ralph Waldo Emerson once said: "Passion, though a bad regulator, is a powerful spring." It is an apt saying for 67-year-old Mun Chor Weng, for whom a simple suspension spring fuelled what has become a lifelong passion.

Mr Mun is a Singaporean pendulum clock collector and restorer - one of only a handful in the world - whose collection of over 200 torsion clocks holds some historically significant pieces.

Over the years, his unrelenting passion has turned him into an authority on torsion clocks. He is a founding member and director of The International 400-Day Clock Chapter No. 168 and is considered by many to be an expert on striking clocks, having published almost every article written on the subject in the last 10 years.

The retired biology teacher grew up in a clock shop. His father was a clock repairer and the young Mr Mun, who had picked up basic clock restoring skills, would collect "simple" clocks like quarter chimes and Viennese regulators. A quarter chime, as its name suggests, chimes every 15 minutes, while Viennese regulators are a style of antique wall clocks that originated in Vienna and is renowned for their exceptional quality.

In 1975, a friend gave Mr Mun a torsion clock in need of repair. Torsion clocks, Mr Mun says, are notoriously difficult to maintain and fix. Even the smallest disturbance, like a gentle nudge, can affect the clock's adjustment. Hence, repairers tend to shun these clocks as sometimes, their clients would collect the repaired clocks only to find upon reaching home that the clocks' adjustments have gone askew once more.

Up for a challenge, Mr Mun tried his hand at repairing the clock. "There are only five gears in a torsion clock, so I bought a suspension spring and had a go," he said excitedly. "It wasn't that difficult - I repaired it. And from then on, I was hooked!"

Mr Mun began buying more torsion clocks and spent much of his free time learning how to repair them.

He became so deft at repairing these clocks that he eventually disproved Charles Terwilliger, the noted author of the 400-Day Clock Repair Guide, who wrote: "Everyone who owns (a torsion clock) will confirm that it is difficult to get the clock to strike properly."

Mr Mun compiled a detailed article on the "Common Problems In 400-Day Striking Clocks" and how they could be overcome. The article was published in March 2005 in The Torsion Times, the quarterly journal published by The International 400-Day Clock Chapter No. 168.

Sitting on a goldmine

Torsion clocks are pendulum clocks that are also known as 400-day clocks or anniversary clocks. "Torsion" refers to the twisting motion of the pendulum, while "400-day" refers to the amount of time the clock can run autonomously after being fully wound. The Americans coined the term "anniversary clock" as they were often presented with it as a gift on their birthdays or anniversaries.

The bulk of torsion pendulum clocks produced in the last century were made in Germany. Yet, only a handful can be found in German museums. These clocks are no longer in production. So many visitors at this year's Tempus - The Temple of Time were surprised when they came upon Mr Mun's extensive collection of lovingly restored torsion clocks. "Even the Swiss watch dealers who came here expressed surprise at the vast collection we have here in Singapore," said Mr Mun as he beamed with pride.

Among his collection are seven rare clocks from The Horolovar Company, once owned by Mr Terwilliger. The earlier versions of Torsion clocks were very inaccurate, being affected by normal temperature changes. Mr Terwilliger developed a temperature compensating suspension spring that enabled the 400-day clock to keep time decently, and made it acceptable to the populace in the 1950s.

Another clock, a rare Schnekenburger wall striker housed in a pristine walnut case, was once owned by the legendary millionaire collector Joseph Meraux. "This clock has worked for over a hundred years," Mr Mun enthuses.

There is a wall clock with a rare verge escapement made in 1881 and an early cylinder escapement clock dating back to 1875. The escapement measures beats and controls the speed of the linked mechanical parts in a watch.

Some clocks Mr Mun acquired several decades ago for $5,000 are now worth six times or more their original price.

"To me, the clocks are not commodities. I am not a dealer. Even if I make a healthy profit selling one of these clocks, I lose a part of my heart. Everything I do for this hobby is voluntary. I'm just so passionate about it," he says.

When asked if he will leave his collection to his three children as his legacy, he smiles and says: "I don't want to think that far. For now, I am just enjoying my hobby."