Could the future of fishing rods be triangular?

The future of rods may no longer be round, it could be D-shaped. That’s the shock news this week following the launch of a radical concept in fishing rod design which could see the traditional round cross-section of a rod blank consigned to history.

New ‘D-Flex’ technology invented by fly-fishing physicist Dr Chris Underwood allows the manufacture of rods with an over-emphasised ‘spine’, meaning they are significantly stiffer bending one way than the other.

This unique property is the result of Chris having based his design on the fact that an equal-sided triangle has more integral strength than a circle, a factor incorporated into the unique ‘extended Reuleaux’ shape of D-Flex’s cross section.

“I first developed the idea when learning to Spey cast while salmon fishing a few years ago,” explained Chris, whose 30-year career has been spent designing artificial blood vessels.

“A triangle isn’t practical for rolling rod blanks, but the shape I have come up with - a unique piece of geometry called a curve of constant width - is perfect for fishing rod manufacture,” he claimed.

According to Chris, the D-Flex cross section reduces stress loading, making casting control easier, more accurate and significantly more powerful, and can be used to make rods for fly fishing, spinning, waggler fishing, distance casting and even pole fishing.

With the sale of fishing rods exceeding 100 million annually, Chris is looking to sell his design concept to any major rod manufacturers who think it might help them secure a larger share of the $5bn a year global market.

It’s not the first rod blank design to steer away from the norm. In 2007 Shimano launched its ‘Aerocast’ rod based on Oval Blank technology that provided a stiffer casting action and a softer fish-playing bend.

And according to one leading carbon fibre manufacturer, Tricast, the new D-Flex concept has merit.

“We looked at triangular blanks around 15 years ago and concluded that they would be best served in a fly rod. When it comes to this D-Flex design we felt it would be most suitable to a salmon fly,” explained Tricast’s sales and marketing director Roger Harris.

But others have questioned how expensive the D-Flex rod mandrels - the steel tubes that carbon fibre sheets are wrapped round to make rod blanks - will be to manufacture.

“We developed a curved carbon throwing stick and it was a nightmare to make using standard technology,” said Daiwa’s marketing manager Stephen McCaveny.