Bob Evans Designs-VAULT

[Blair Mott]

Bob has amazed me again by sharing these photos and some words about one of his older blade designs. Enjoy another piece of Force Fin history.

ABAF
Adjustable Blade Action Fins.

“This swimming blade was designed to adapt different flexible fiberglass battens. This PRE-dates other fin designs that used battens and it shows that I have always have been designing and thinking about how to make a better fin. All I do is create fins. Other Force Fin prototypes allowed the battens to be pulled back under the foot area changing the stiffness of the blade.

We also used surgical tubing to change fin blade stiffness but found Force Fins preformed better by adding winglets; which are now part of our Force Wing accessory line that allows the diver to use variable thrust technology by simply changing the angle of the attached wings. Winglets control water flow which changes blade flexibility from flexible to stiff."


Force Fins - We have been changing the way water flows over you fins!

 

[Blair Mott]

As I walked into the pearly gates of Force Fin today I noticed a pair of fins that I had never seen before. No surprise as Bob has been designing and producing the most innovative fins since 1981. What really caught my eye was that it had a very similar shape to my favorite Force Fins the Excellerating Force Fin. Tin this fashion. Sacred fin “don’t Touch” I thought. As the phone started ringing I started to man the front lines of Force Fin HQ.

Later in the day Bob Evans brought me the fin for a closer look. I immediately recognized the flat blade that is on the Rip Force. I knew the fin was decades old, but Bob proceeded to show me the flex and rebound in the blade and I was impressed again with the materials Force Fins uses to make their fins.

Bob explained to me that when this blade goes through the power stroke in the kick cycle water wants to spill off the sides, so he began to experiment with a flat blade design and adding a series of Force Wings attachments to the blade to increase tracking, advance performance and change the way the water moves over the fin blade.“This baby flew through the water” Bob Evans

He also began to use two designs elements that were firsts in the fin market and part of his signature finovations found in certain Force Fin models today. One is the first adjustable foot pocket that could accommodate a variety of foot sizes and second- my favorite - is the distinctive ribbing on the backside of the blade that “gave my signature of POWER and RECOVERY to the design” Bob Evans

The whiskers are not attached with the gear surfaces as they are today and were tested inline with the fin blade. This fin went through many other changes that finally landed into today’s Excellerating Force Fins.

Backside of the 2002 Tan Delta Excellerating Force Fin

 

[Bob Evans]

Blair, Thanks for posting the winglet testing I did years ago. The idea of using surgical tubing to change fin blade flexibility came first and will find those fin experiments as I clean up 35 years of fin designs. I found that changing the silicone tension I was able to change the stiffness of the fin blade..but it was the same surface area moving thur the water. Nothing really changes BIG with this type of design, plus it had a way of breaking over time and was hard to change with cold hands. The Force Wings work with the water changing the blade flexing in a way that works and makes sense. When you spend half a life time making all sorts of fin designs you find what works and what ends up in the R&D box. Just like those fins with the hinging device that are splitting. I also tried that approach but it failed due to the hard flexing and split, right at the split.

 

[uncleavi]

Bob,
Tester # 1 fell off a Scaffolding and got hurt but, looking at you fins make me feel better.

 

[csicnomore]

Avi, Hope your completely better soon.

 

[uncleavi]

Thank you very much. I am seeing the Orthopedic folks tomorrow.

 

[Blair Mott]

Uncleavi,
Looking forward to hearing the good news tomorrow after your visit with the Doc. Our prayers are with you and to a speeding recovery!

 

[Blair Mott]

Uncleavi,
You face a long recovery and we wish you the best! This is not your first rodeo and we know you will be making great strides in the healing process. In the meantime keep diving and Explore the Ocean with eDiving ! You can even dive your Force Fins.

eDiving is very dynamic and is packed with useful simulations. Salutes to DiveNav and what you are doing to improve and promote diving!

 

[Blair Mott]

Just had to pull this from a previous thread as it really shows that Bob Evans is always trying to design a smarter fin.

Bob Evans in his workshop displays a fin concept he tested in 1999. Modeled from a Tuna tail. Water is weaved through the Red Force Fin attachments.

 

[Blair Mott]

Another example of the diverse blade attachments for the Force Fin Launch Pad Foot pocket.

Bob Evans has designed numerous blades ( like the OPS Force Fin ) that are suitable for a wide range of water activities. It is simple - attach the blade for the right dive or environment to the Launch Pad and you are ready to get wet.