When medical undergraduate Jonathan Han set out to buy a watch more than two years ago, little did he know he would end up starting a bespoke timepiece label.

Schaffen - the online start-up that he set up with his elder brother Nicholas - retails watches that are custom-built to suit different tastes, lifestyles and preferences.

A fourth-year medical student at the National University of Singapore, Jonathan, 22, said it all began when he failed to find a watch he fancied.

"I had certain criteria: price, movement and the materials used. There were some options, but none which I really liked," he recalls.

Trawling watch websites, including hobbyist ones, threw up an intriguing possibility: assembling his own timepiece.

"I am good with my hands so I thought I'd give it a go," he says.

He spent $500 shopping for different parts, including a stainless-steel case with sapphire crystal from a German online retailer and a Chinese mechanical movement from eBay.

There was a lot of trial and error. "I kept removing and putting things back together again," he says.

With a sheepish grin, he says what he finally came up with did not keep good time at all. "But it told me that building your own watch was definitely feasible and possible."

The exercise fascinated his father, a regional manager in an ink company, who asked him to build him one.

Jonathan did, this time to perfection, using an ETA 2824, a famous Swiss movement used in many watches. He even inscribed his father's signature on the dial.

"My father really liked it and showed it to his friends and colleagues," he says.

He sounded Nicholas, 25, out on the idea of starting a business selling affordable and good quality watches where customers get to choose their own dial, hands, strap as well as inscriptions on the dial and caseback.

A final-year economics and business student at the Singapore Management University (SMU), Nicholas says he was initially sceptical of the idea. But he was more than game to help Jonathan explore it.

When the two brothers found out about a watch fair in Hong Kong, they decided to fly to the former British colony.

Nicholas says: "We learnt a lot at the trade fair. Everyone was there, from people manufacturing watches to those selling glass displays for timepieces. We met 60 suppliers along the chain and came back with a good understanding of what it would take to be a player in the industry."

Probably because of their youth, the duo were at the receiving end of some snarky remarks. "We told a major player we planned to inscribe personal details on the watch. He said sarcastically, 'How will you do that? Using your pencil?'"

They took it in their stride.

Nicholas put what he had learnt in his business studies to good use.

"I've had a few mentors and the first thing they teach you is to validate that you have a customer base," he says.

At the watch fair, he and his brother interviewed at least 100 people. "We asked them what they thought of our idea and if they would pay a premium for customisation," he recalls.

They also did surveys at Changi Airport to find out what styles were popular.

The response was encouraging. Nicholas says: "About 88 per cent said they would pay a premium if they could customise their watches. They said it was unique and made owning the timepieces more meaningful."

The surveys also showed that dress watches were the most popular.

Realising that they would benefit from all the help they could get, the brothers applied and got into an incubation programme at SMU's Institute of Innovation & Entrepreneurship. The year-long programme helped them plot the different stages of growth and culminated in a pitch to investors.

With the help of their father, the brothers put in more than $50,000 to get Schaffen - which means "to create" in German - rolling. They sorted out the supply chain and got on board a veteran watchmaker who has worked with some of the biggest names in the business.

"Initially, he thought we were one of those who didn't care about the quality of watches. But when he met us, his opinion changed and he came on board," says Nicholas, adding that the veteran trained the watchmaker now engaged on their payroll.

Through the incubation programme, they received a couple of offers for equity funding from interested parties. But they opted for debt funding and to work with key advisers, one of whom is a serial entrepreneur and another, a former creative director at Walt Disney.

Equity involves selling interests in the company to raise money while debt means borrowing money to be repaid.

"We wanted to start small. If we had gone with institutional investors, they would have expected us to scale up much faster," says Nicholas, adding that Schaffen operates out of a small workshop in Jurong.

Besides a full-time watchmaker who assembles all the watches, Schaffen has a team of freelancers and interns to help with assembling, administration and marketing.

The brothers are also heavily involved in the business. Nicholas, Schaffen's CEO, will be running the business full-time when he graduates next year. Jonathan has a six- year bond to serve after graduating from medical school.

Since last October, more than 300 Schaffen watches, priced at $300, have been sold. Orders have come from as far as Germany, the United States, the United Kingdom and Lithuania.

Sales surged especially after the company started collaborating with Filipino artist Kerby Rosanes whose "geometric beasts" illustrations have earned him a huge international following. A couple of exclusive Rosanes drawings are available for engraving on the caseback of Schaffen watches.

Besides selling their watches on the official website, the brothers have also gone into tie-ups with K+, a pop-up space in Scotts Square which champions works and products by local artists and designers.

Their latest platform is Just Two Questions, an online store selling stylish home decor and lifestyle goods from independent designers and artisans in the region.

Meanwhile, the siblings are planning to release two new models with Swiss automatic movements, costing between $700 and $1,000, later this year. The current models have quartz movements.

"We will be pushing personalisation and customisation to a greater degree," says Nicholas.

Jonathan adds: "Our ambitions are not huge. I wanted an alternative watch product, one which is good-looking, well built and allows you to have a say in the design."

Nicholas agrees. "We do have dreams of going international, but, for the moment, we just want to fill the niche of a micro brand, one which makes bespoke watches."