Bob Evans Designs-VAULT

[meesier42]

Jet fins can be made out of anything from rubber, polyurethane, monoprene, wood, metal, to latex coated cloth reinforced pressure sensitive tape (aka Duct Tape) and it wouldn't change the performance one bit.

To be honest, a couple years ago Bob tried a version of the UDT fin (aka Duck Foot) and it was basically worthless. There was a glimmer of potential there, but the footpocket and flex profile basically made it a flop. Even with all efforts to modify the footpocket failed to make it something usable. Pretty, but that was about it.

The Flying Force isn't really a more refined version of the Pro/Original, it doesn't frog any better then they do. The Excellerator and the Hockey are the 2 better frog kicking fins out there.

 

[huwporter]

Jet fins can be made out of anything from rubber, polyurethane, monoprene, wood, metal, to latex coated cloth reinforced pressure sensitive tape (aka Duct Tape) and it wouldn't change the performance one bit.

I don't think that is really true - I certainly prefer the performance of my Scubapro Jetfins (rubber) to my OMS Slipstreams (monoprene) despite the fact they are a (completely) identical shape. The Slipstreams don't have the same springyness to them, have a tendency to fold rather than flex under high stress. I would expect the tan delta material would have an even nicer springyness to it than the rubber.

I've owned Excellerators, I'd certainly give the hockey fins a trial if I had an opportunity, but not to the extent of buying a pair and having them shipped over, particularly since I'm far from dissatisfied with the performance of my current fins.

Like I said, I'd buy a pair of tan delta Jetfins on spec (so long as they were black, natch ), but I can certainly understand Force Fin HQ being reluctant to consider the idea given their maveric brand positioning.

Cheers,
Huw

 

[Blair Mott]

To put it to rest Force Fin will never make a jet fin knock off as Bob is convinced he wants to keep moving forward and not backwards with fin design and increased efficiency when it comes to moving through the water.

 

[Blair Mott]

Thanks again for all your posts they are much appreciated. I will be moving some of these posts to the Design and Materials thread for what I believe are obvious reasons. This is Bob Evans Design Vault thread after all.

Why did Bob Evans aka Fin Doctor choose polyurethane over any other material or manufacturing process for his Force Fins? Rebound, snap and recovery. When you are ready to investigate the design and materials used in Force Fin products, you are ready to understand how and why Force Fins are the most efficient fins on the market.

Polyurethane is an elastomer, a class of plastics designed to mimic the characteristics of rubber…. And then some. The special polyurethane formula used in Force Fins has been designed to maximize its SNAP. Some of us might remember it as a “super ball” effect. The energy that is put into flexing the material (as in kicking on the power or downward stoke) is stored then released as rebound energy. A kick with power and recovery is the most efficient, but Force Fin gives you even more. When the fin snaps back on the recovery or upstroke, water is thrown behind at a faster rate than you can kick any other fin through the water. Propulsion during the recovery is unique to Force Fin

Force Fins are one solid material so the energy applied and extracted are not loss or filtered out by having to go through different materials that are glued, fused, bonded, bolted or tied together. This is one reason that makes kicking Force Fins so naturally efficient.

We have received countless comments from customers explaining how natural the fins feel when kicking them. Their first impression is that the fins are not even on their feet. I talked to a research diver last week and he told me he uses Force Fins. His first impression was he jumped in the water and thought he was not going anywhere and almost started to panic when he looked to his side and saw that he was fast approaching the oil rig and understood his energy input to energy output in his new fins doubled.

Some of this is due to the patented open toe design and the upturned trailing edges, but it is the rebound or snap of the fin that releases a force of propulsive energy. It happens automatically on the recovery phase of a kick cycle in response to compression of the structure of material within the Force Fin blade. The structure is most apparent with the backside ribbing of the Excellerating Force Fin.

During the recovery phase of your kick the recoil gives propulsion without any real energy input from the diver or swimmer.

To free your body, you must first free your mind. If you have been using other fins for sometime, then you should commit to dive Force Fins 3 or 4 times to allow any mental and physical conditioning your mind and body have built up over the years to fade away. Then you will be ready to welcome the freedom in using Force Fins.

Materials - Poly Who?



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