‘Crinkle Cut’ And 3D-Printed? Surely It Ain’t Surfing

Remember the revolutionary* golfball like dimpled fins from 3D fins? Or the dagger-esque rudders from Cheyne Horan that were more knife-like than surf fin-like. 

Well, they weren’t exactly revolutionary, and other than the types of materials used and the entry systems developed, there hasn’t been much in terms of fin re-designs that have definitively worked, or at the very least made a mark.

Now, there’s a bunch of University of Wollongong professors and researchers who think they’ve printed the next shift in fin designs – that’s more analogous with fried potatoes than surfboard fins. And somehow pitched a grant so convincing they spent six days surfing Macaronis loosely veiled as ‘research’. 

Other than scoring a government-funded surf trip though, the researchers aimed to try and develop a 3D printed fin that went beyond the typical rake, cant, and base width designs of which rudder discussions typically revolve. Similar to what 3D fins did with their golfball inspired design, UOW decided to focus upon the fin’s exterior.

“3D printing enables us to print virtually anything we can imagine and that includes surfboard fins,” said Dr Beirne from UOW.

Geez it’s tough being a researcher at UOW

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UOW

“Think of a potato crisp, hence the name crinkle cut,” Professor Marc in het Panhuis said, and based on the images, he’s bang on. Like a crisp, the fins have crinkles cut out, in this prototype through the bottom third of the fin, which is argued to ‘improve the way the water flows past it’ and to ‘increase [the] lift to drag ratio’. Essentially, the crinkles in the fin act as miniature foils, which as you and Kai Lenny know, increase lift. 

The researchers first conducted tests in small controlled environments and found the fins to perform better than the typical fins on the market in terms of objectively measurable criteria – drag, lift etc.. But the only way to truly assess the subjectivity of performance surfing – I’m looking at you speed, power and flow – is to surf actually place the fins in a board and surf them; as fin performance and more broadly surfing goes far beyond easily defined or measurable variables.

But to make it a little more scientific than what surf R & D typically involves (rider feedback), UOW ensured the surfers were ‘blind’ to the fins they were using and monitored speed, number of turns, and the amount of rail engaged and other data via onboard recorders. 

Six surfers – three goofys and three natural footers – from the uni travelled over from Wollongong to Macaronis for less than a week to test out the fins. In science, a non-variable canvas is what you pine for, and aside from wavepools (Kelly’s isn’t open to research just yet) Macaronis is as close to replicable as you’re going to get – plus the tropical waters, superfluous tubes and distance from the uni’s HQ weren’t downsides either, surely. 

“Now if you could just plop some safety glasses on your head so it at least looks like you’re not purely talking about surfing.”

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UOW

“We tracked and counted our participants surfing more than 450 waves and performing more than 1700 turns in all types of weather conditions over six days, for up to eight hours per day,” said Professor Steele, but we’re still unconvinced surfing in Sumatra truly constitutes a day of solid research – it certainly trumps crunching data on a computer back in the lab.   

The fins are still in their early stages of development, but in addition to positive early data, the surfers blindly selected the ‘crinkle cut’ prototype fins as their preferred from the set of three tested; now they’re hoping of a company will back the tech and place it into production. Or if you own a 3D printer you could probably print out a set yourself. 

The data isn’t published as of yet – they’re analysing it now – but if it’s as convincing as they’ve alluded to, then perhaps it’ll be a hit.

Brent Connellan putting the crinkle cut’s through their paces.

Photography

UOW

Author’s note: We’re psyched to see Brett Connellan back in the water and ripping after suffering a harrowing shark attack back in 2016 at Kiama. His surfing’s almost good as it was previously, and while he might not be in top competitive form just yet, his surfing takes centre place in the above clip.