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.
Here’s the latest foam mold and the glass blade made with 9x 6 Oz and epoxy resin.
And fitting the foot pocket to the first blade.
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.”
I think the "fins" on the outside edge have potential. But for safety, I think you need semi-soft/flex twin-fins like these:
Swaylocks Surfboard Design Forum: thoughts & theories ... practical & theoretical
RAIL PROFILE http://bgboard.blogspot.com/2014/03/march-82014-afterr-seeing-recent.html
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.
So on the down stroke which is the power stroke the flipper with a single side fin gives a lot more drive as expected.
What I didn’t see beforehand was that the flipper was unbalanced during the stroke because of the resistance from the side fin.
with the side fin it slows the flow off that side of the flipper and because of the greater resistance the flipper rotates as it moves thru the water.
It will need a balance design that allows the blade to stay horizontal thru the kick.
Seems like you have a design trade-off to consider -- tracking vs. thrust.
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.
sent you an email.
The side fins on the flipper do give more directional thrust than a flatter flipper.
Having the fins closer to your heel creates thrust sooner during the kick arc.
Ill have a think and come back with a design.