WoodDave, no directional control but I’m addressing that with the next pair of flippers.
Bob, no contact with reef at all. You know how some people are lucky in love or always happen to get the best deal. I’m the guy that never hits the reef. Having said that I’ll probably get flogged and cheese grated tomorrow.
All the commercial fins are pressure molded so they have to bulk up to create rigidity but I’m using glass so I should be able to make flippers that are much lighter with flex and swap in other materials for a perfect fit. I’m thinking a rubber heel strap but with a silicone foot pocket for comfort.
I also want to see how I can turn up the sides to direct the water straight out the back when you kick as well as providing some real direction hold and control for your feet.various brands talk about it but I’m not feeling the control as advertised. Maybe have the blade sides 2 or 3 inches high, but Flippers with real hold would revolutionise body surfing.
So here’s the foam mold that I’m going to glass over. It will create a sole with both sides angled up and out to grab and hold more effectively that a flat fin. As it’s just the blade and sides I’ll add the heel strap and foot cover later. I’m thinking silicone for both maybe even a silicone lining inside the flipper.
By having both sides angled it should control the water against the blade and direct it more efficiently off the end of the blade rather than washing off the sides.
The sole of the flipper is the same template as the Voit Duck Feet.
The wider top template is from DaFin so I’ve covered some of the argest and widest popular flippers.
im hoping that are more effective design will bring improved performance. If the sides create better drive they may need to be smaller overall.
The other aspect is the shape of the angled sides to give real control for bodysurfing. With increased grip you wouldn’t need to be Cunningham to tube ride. I can see 2 variations of the sides that could work. First putting the area increasing towards the end of the flipper so the sides work like rear surfcraft fins. The second is to put the most area closer to the middle of the length of the flipper so it’s closer aligned to where you have control with your feet.
It’s a simple vac system. Vac then tube into bag. The tube is perforated inside the bag with an old t-shirt wrapped around it so the holes dont get blocked by the bag or resin.
I’ve found that a longer flipper gives a better response than a wider flipper.
Out of the mold and even with just 6 layers of glass it’s quite rigid but has some torsion so rather than lay another 6 or maybe 12 layers , I’ll first trim it down to shape and then look to specifically strengthen it in certain planes.
The Voit weighs 675g, the DaFin weighs 350g and this glass one weighs 260 but will probably hit the middle ground.
Ive just ‘pool tested’ it and the sides definately give a lot more resistance so it’s holding water better and it feels like it’s shooting water directly out the back. The widest point of the blade end is 9 inches but I think I’ll do another mold just 6 inches wide. Like Bob Green said about the stiffer blades being a chore, this 9 inch size is a lot of work so a smaller version is needed to get it closer to current flipper feel.
I kept the anhedral sides as full as possible. Even in basic water tests you can feel them forcing the water along the flipper.
so I’m doing a new design with a max width of just 6 inches, ( compared to Da Fin at 9 in) using the anhedral sides to create a smaller but more efficient flipper.
Given a few days to think about anything , I come up with ideas like…
being as the downkick is the useful stroke, maybe the blade should be on top of the foot instead of under it ?
but there’s already a lot to do so I’ll keep that ideas for later.
With the new side design to play with I thought why stick to a constant angle ? Why not have the sides grab max volume quickly in the stroke and then direct as much of that water down the blade.
So here’s the new design, a slimmer blade, but with the sides angled out at 45 deg near the foot, and then wrap the sides in slowly closing the flow with the sides up near 90 deg at the end of the blade.
The heel strap pulls the foot forward into the foot pocket but the common comment about flippers is poor fit so I figure to make a fitted left and right pocket.
Yes guys , I figured out that while doing a Left and a Right is customising, it’s also double the work. Bob, you’re right, it’s possible to make a universal foot pocket that does Left and right quite comfortably. See pics below. I had a thought about water ski bindings I used many years ago and translated that to flipper design.
i use clear vinyl so I can see how the foot is fitting.
And the last pic is of the latest blade design with the angled sides flared out wide close to the foot to grab water and then standing up vertically closer to the end of the blade to effectively channel the flow out the back.
interesting that the wider the blade is closer to the foot, the greater the force possible.
And here’s the foam mold, Wooda had it done sooner but the surfs been like blue champagne this week.
You can see how the the sides an out close to the foot and then square up to channel the water put the back. I’m hoping the square sides will act like surfboard fins and give some real hold in steep waves.
I also picked up some 3/4 in EVA strap for the heel strap and 4 mm EVA sheet for the foot pocket.
Moving the area closer to your heel gives better torque for the essential few kicks to get on a wave so I’ve moved these panels higher. The Darin’s have more area higher and I’ve been riding them day after day learning how the shape works. I like the side panels that tilt up, I think they give a bit more direction that a flat flipper.so I’ve added some side fins to the flippers, first with 2 side fins on each flipper and then with one fin on the outside of each flipper so they’ll be on the inside of the wave face.
I can move these fins back and forth, toe in or out to test what effect each variation has.
“You never know if you’ve gone far enough until you’ve gone too far.”
Have to test having the inside fin or both side fins , am thinking both sides will have better torque / push and hold. I’m never concerned about safety in the surf, I’ve ridden so many foils for 14 years now and never lost skin or blood. I feel completely at ease for some reason with carbon and aluminium.
Having said that, I’ll probably lose a leg on the next wave.
Yes Bill, any sort of tracking would be new and good for grip on the wave when bodysurfing or bodyboarding. One of the problems with body surfing is slipping when it’s tubing, I think everyone’s had the dream of pulling into a tube and bodysurfing out of it. Combined with a handplane it could give a full surfing experience with the minimum of equipment.
So I tested the top version with the area closer to my toes, it’s good, plenty of thrust but I feel the thrust is from the end of the arc of the kick,I’ve got to fully snap my leg to get maximum thrust.
So the next version ( 2nd pic) is to bring the side fins closer to my heel, bringing the resistance closer to the power in the kick. Having that lateral resistenace might be the best place to put the fins for control.
