FINSCIENCES MODERN SURFBOARD FINS AND SUP FINS

FAQs About FinSciences Fins

FAQs About FinSciences Fins 1

FAQs About FinSciences Fins

What's the difference between FinSciences stiff and semi-flex fins?

Our semi-flex and stiff fins all have the exact same shape.

But our semi-flex fins give a bit of “pop” when coming out of bottom turns—they have a bit of liveliness to them. If you take our longboard fin (the WG2) in your hands and push hard from the ends into the middle with your thumbs, maybe you’ll get about 3/8″ of tip flex—not a whole lot, but enough to be noticeably different from our stiff fin. The semi-flex fins are translucent (you can sort of see through our clear, blue, and orange fins), except for the gloss black, which is totally black.

Our stiff fin is made with fibers that eliminate flex. With both hands on the ends pushing into the center of it, you won’t notice any bend. Some surfers report that they prefer the feel of this fin. The stiff fins are opaque, with a matte finish, and they’re currently available only in black.

What size fin or fin set should I buy?

A good benchmark is what you’re surfing or paddling with now—find out the total area of your current set in square inches (for the math-challenged: length multiplied by height = area). Now what you want to do is buy a set of our fins that is 20 to 30 percent smaller than what you currently have. Use our fin size calculator page for more detail about this.

Longboards and SUPS

For longboards and SUPs we have a 9¼” WG2, which has 30.7 in² area. The WG2 works really well as a single fin, even if your current board is a 2 + 1 setup. For bigger surfers, and more classic, hard-to-turn boards with flatter rocker and softer rails, add in sidebites, starting with small 4.8″ fins for a total 2 + 1 area of  50.88 in². If you feel you really need lots of fin, which is rare, go with the 5.7″ fins for a total 2 + 1 area of 59.8 in².

Ride a thruster setup? Try three of our 4.8″ fins. Most surfers find that setup does the trick—and it’s a lot less area (30.42 in²) than surfers are used to. Most medium thruster fins on the market today measure about 14.5 in²—giving you a total area of 43.5 in². So if you compare the area of your set to a FinSciences thruster set (30.42 in²), there’s a drop in area of about 30 percent, which gives you more speed. For a bit more hold, add in our 5.7″ fin as a tail fin. See more on our fin size calculator page.

Quad Setup

Ride quads? Most people do well with a set of four 4.8″ fins, which has a total area of 40.56 in². This is a big drop in area from a typical set. If you feel you need more bite than the four small fins, then get two 5.7″ fins, giving you 49.44 in². Or you could go big, with four 5.7″ fins, but this is a lot of fin, generally not necessary even for larger riders on harder-to-turn boards.

I want to replace a thruster set. What should I buy?

Ride a thruster setup? Try three of our 4.8″ fins. Most surfers find that setup does the trick—and it’s a lot less area (30.42 in²) than surfers are used to. Most medium thruster fins on the market today measure about 14.5 in²—giving you a total area of 43.5 in². So if you compare the area of your set to a FinSciences thruster set (30.42 in²), there’s a drop in area of about 30 percent, which gives you more speed. For a bit more hold, add in our 5.7″ fin as a tail fin. See more on our fin size calculator page.

I ride a longboard. What should I buy?

For longboards and SUPs, get a 9¼” WG2, which has an area of 30.7 in². The WG2 works very well as a single fin, even if your current board is a 2 + 1 setup. For bigger surfers, and for more classic, hard-to-turn boards with flatter rocker and softer rails, add in sidebites, starting with our small 4.8″ fins, for a total 2 + 1 area of  50.88 in², and if you feel you really need lots of fin, which is rare, go with the 5.7″ fins for a total 2 + 1 area of 59.8 in². See more on our fin size calculator page.

I want to replace a quad setup. What should I buy?

Ride quads? Most people do well with a set of four 4.8″ fins, which has a total area of 40.56 in². This is a big drop in area from a typical set. If you feel you need more bite than the four small fins, then get two 5.7″ fins, giving you 49.44 in². Or you could go big, with four 5.7″ fins, but this is a lot of fin, generally not necessary even for larger riders on harder-to-turn boards. See more on our fin size calculator page.

What fin boxes or templates do FinSciences fins fit? FCS? Futures?

The 9¼” WG2 fits Bahne and Fins Unlimited standard longboard fin boxes.

The 4.8″ fins and 5.7″ fins fit FCS1 and, with an adapter like the Wasabi Surf adapter, they fit Futures bases.

What are the fins made of?

We use Lexan® polycarbonate, a material that is used in bulletproof glass, fighter-jet canopies, headlight lenses, eyeglasses and other applications requiring great strength. There are many different brands of polycarbonate, and Lexan® itself has dozens or perhaps hundreds of varieties with various specifications. We chose two kinds of Lexan®, one without fiber that is translucent for the semi-flex fins, and one that has a percentage of fiber for the stiff fins.

Do I need sitebites with the longboard fin? Will the WG2 work with sidebites?

Yes, the 9¼” WG2 fin will work either as a single fin or as part of a 2 + 1 fin setup.

But really this is a question of how much fin you need in total, and what is your preference for speed versus turning. How much turning force do you need or want? For paddleboarders, how much resistance to turning, or how much tracking ability, do you need or want?

As a general concept, smaller fins will be faster because they have less area, and thus less-skin friction drag. Think sports car versus SUV.

On the other hand, larger fins will produce more power—more side-force/lift/hold for more turning ability or for resistance to turning—tracking ability.

We advocate a reductionist philosophy—less is more—and recommend the smallest surfboard-fin surface area that gives you the turning and tracking ability that you want.

So what is just the right size?

Fins with winglets, like airplane wings with winglets, behave as though they are about 20–30 percent larger than they are in terms of producing lift (hold and drive), while having less drag because of their smaller area. So if you have a typical 2 + 1 fin setup, a typical center fin of, say, 46 square inches, plus two sidebites of 14 square inches each, your 2 + 1 fin setup has a total fin area of about 74 square inches. You can pop out the center fin of 46 sq. inches, pop in the WG2 of about 30.7 sq. inches, and you have dramatically reduced your total fin area—a 21 percent reduction. If you’re like other surfers, you’ll feel a significant improvement.

But why stop there?

We recommend that you try surfing with the WG2 as a single fin—it produces a lot of side force by itself, more than adequate for most surfers’ turning and maneuvering needs. And, by removing the sidebites, you’ve reduced your total fin area by 59 percent versus the typical 2 + 1 setup.

Use the scientific method to test your new FinSciences fins. Stick the the sidebites in, ride a few waves, pop them out and ride the WG2 as a single fin, see what you think. Lots of surfers find that removing the toed-in draggy sidebites and using only the WG2 really improves performance.

What's the size of these fins compared to what I normally ride?

We’ve Maximized the Power of Our Fins

Our fins have a lot of power. They generate a lot of hold and drive for their small size. In more scientific terms, they have a lot of lift per unit of drag. The smaller area still gets good hold—and the smaller area means less drag, more speed and acceleration, easier paddling, and longer surf sessions.

Finlets and other features we use make our fins about 20 to 30 percent more efficient than larger, older styles.

As a result, our fins are a lot smaller than you’re used to.

A typical medium fin is roughly 4¼” with about 14.5 in² in area. Our comparable fin is the 4.8″ with 10.14 in² fin area—a 30 percent reduction in area—less skin-friction drag.

In other words, our fins have the power (hold and drive) of a set of three typical thrusters, but with the drag penalty of only two. This means more speed and better acceleration—bigger air if that’s what you want.

So you need to downsize from your current set by about 20 to 30 percent. Less is more. Less drag = more performance. See our fin size calculator page for more about this.

 

Where in the surfboard fin box should I put the FinSciences WG2 fin?

About 2 inches back from where you locate a typical dolphin fin (see diagram).

Because the FinSciences Surfboard/SUP fin is an upright (or low-sweepback or low-raked) fin, we recommend putting it back in the box about 2 inches from where you place a typical dolphin-shaped fin. This will pretty well line up the center of area of your current fin with the center of area of the WG2.

But that’s just a place to start.

We recommend putting it even further back in the box if in doubt.

Another benefit of using our fin is that it has a very short fin base, a bit more than 4″. This means that in an 8″ box, you have 4″  of adjustment. Most typical fins are about 6″ in the base, leaving only 2″ for adjustment. Bummer. Try the WG2 all the way back in the box. Just don’t tell your friends.

FAQs about FinSciences Modern Surfboard Fins

Start with the WG2 about 2″ back inthe box. Or move it even further back.

 

 

Can the WG2 longboard/SUP fins carve wide radius turns? Is the WG2 just a pivot fin for pivot turns?

The WG2 fin is an upright fin. But thinking of it as a pivot fin that can’t go straight isn’t right.

First, fins generally have forward velocity, they aren’t just rotating by themselves.

Second, in terms of hydrodynamics, surfboards don’t pivot around the vertical axis of the fin. Instead, pivoting or rotating occurs around the Center of Lateral Resistance (CLR), which is the center of the sum of the areas of the board-and-fin system that’s immersed in the water.

Fins, of course, have a lot of lateral area and are a big factor in where that pivot point is. We can imagine pivoting on a board that has no fins at all—the board pivots around the CLR even without fins. If you sink the tail, the CLR moves back, or aft. And if you lean or move forward, the CLR moves forward too.

If we add a fin, the CLR moves toward that fin. If we add a few fins, then we have to figure out the CLR for the fins system, because the CLR of the board alone will shift toward the CLR of the fin system.

Yes, a longer fore-and-aft fin will have more resistance to pivoting, by itself.

But fins are attached to boards and are part of a system comprised of board and fin.

Being an upright fin doesn’t mean that the WG2 can’t do long turns or go straight. Just because a Porsche 911 can turn on a dime and really hold the road on a switchback (while a Hyundai can’t), doesn’t mean the Porsche won’t go straight on the freeway too.

FinSciences surfboard and SUP fins have a high aspect ratio. They are tall and thin. Low-aspect-ratio fins are shorter and squatter. Tall and thin fins have less drag than shorter and squatter ones.

Anybody who calls our fin a pivot fin that can’t go straight or give beautiful wide turns has clearly not tried it.

What difference does the WG2 surfboard fin make?

The key concept behind FinSciences fins is their efficiency. Because they are so efficient, they can be smaller in area, and because they are smaller, they have less drag, which means more speed and power–more hold and drive.

Surfers report easier paddling, and better wave-catching ability. This is key for those big beautiful waves that are sometimes deceptive as to the best spot in the lineup. Also, where lots of other surfers are around, you want to be the one to claim the wave. So smaller fin means less drag. Less drag means more acceleration.

But we put other feature into our fins too. We have a foil share that resists stalling. So when you make a sharp cutback, you don’t lose the wave, as you might with more typical fins that stall out.

Most surfers notice several things.

First, surfers tell us they do feel a difference—and often they are surprised. Lots of surfers have bought other fins claiming this or that, only to be disappointed when those fins didn’t live up to the claims. We’re not selling snake oil here—these fins really work—and are based on solid science.

Second, many surfers report feeling as though they are higher and lighter in the wave, especially when dropping in. This is because they don’t have the tail-sink associated with a draggy fin or fin set; and they’re faster.

Third, many surfers report surprise at the ability of the fin to turn, not only in the wave, but also in the flat or in mush—summer California waves, and some East-Coast waves. This is due to the low-drag features of the fin and the foil shape, designed to maintain lift over a wide turning angle.

Fourth, surfers have described a feeling of “pop” coming out of turns. This is a product of the high-lift, low-drag design features–and a result of the material flex—the WG2 semi-flex has a moderate flex characteristic that loads up then rebounds. The WG2 stiff fin does not flex like this.

Fifth, surfers report easier paddling and better acceleration, both on surfboards and SUPs, as well as excellent tracking ability on SUPs.
All these reports are consistent with our design goals—increasing lift per unit of drag—and make complete sense. See testimonials on our home page.

FinSciences fins look different from what I'm used to. Do they work?

FinSciences fins are different. By design.

Yes, our fins look different. And they work.

We started with a blank slate.We used science.

We didn’t just refashion dolphin fins that have been around for 50 years.

We didn’t use a grinder and sander in our shop and say ummm, this looks good, even though the fin has no cognizable foil shape.

We didn’t just pump out another fin, spray paint it with graphics, and call it good.

We didn’t pay surfers to ride our fins to the exclusion of others.

We didn’t partner with pro surfers and get their names stamped on our fins.

Science proves that winglets work. Winglets make wings—and finlets make fins—produce 20-30 percent more lift for their size without increasing drag. The secret is not just adding winglets or finlets. Instead, FIRST we made a major reduction in fin size, THEN we added  back teeny tiny finlets for an overall reduction in area.

Not too long ago, we’d get on airplanes and puzzle over the winglets on the end of planes’ wings. But now they’re pretty normal—or wings without wiglets are even unsual. This is because winglets work.

Surfers are surprisingly resistant to change. They like retro gear. They figure if it wasn’t adopted by the sport’s grandaddies or film legends of 1950s and 1960s, it must not work. But that just reminds me of a quote from Charles Duell, Commissioner of the U.S. Patent Office in 1899, who said: “Everything that can be invented has been invented.”

Just because FinSciences fins are new and different doesn’t mean they’re bad or don’t work.

Several prominent surfers experimented with winged fins over the years. Some added wings too existing fins, thinking wings are magic. But adding wings adds area. The secret is to chop off like 30 percent of a fin’s area, then addd back a few percent in the right place, for a big overall reduction in area.

Does the WG2 surfboard fin help noseriding?

Yes, but only because the fin allows surfers to maneuver to the best spot in the wave. The teeny-tiny winglets provide little tail-hold-down force—that’s not their intent—they’re about the size of a postage stamp.

Many surfers report excellent noseriding with the WG2 fin. We attribute that noseriding capability to the surfers’ ability to better maneuver their boards to the right place in the wave.

Are FinSciences fins hydrofoil fins?

No. The fins’ winglets are not designed to lift a surfer out of the water—and they don’t. For that there would need to be a much larger horizontal area. The winglets are about the size of a postage stamp. The purpose is to keep laminar flow across the tip of the fin, making the fin tip more efficient.