The Art of Design

The Art of Design
The Innovative Designs of Bob Evans, Erik Buell and Burt Rutan
©1998 Prof. Harry J. Wirth

May 2, 1998

Introduction

Design has many meanings in this world. The context I have chosen here is design as the process of creation. Design can be defined as a noun or as a verb. The word usage I wish to employ here is that of the verb or the action word. The process of design being the creation of an idea or object as a result of a need, want, or desire. As to art, that word has many and varied connotations as does design. In this case I apply the word art again as a process. This would be a process of discrimination to a very high level. Therefore the Art of Design would be the careful selection of concepts as it applies to the creation of an object.

A design exhibition I recently produced was titled “The Art of Design”. It highlighted the design work of contemporary American designers of graphics, products and architecture. The exhibition illustrated the process of design as well as the finished products. The design process was displayed as conceptual sketches and models along with narratives by the designers documenting the evolution of the product development. This method of display allowed the viewers to compare and contrast not only the products, but also the methodology employed by each of the designers. As might be expected, the design process of each of the designers had similarities as well as great differences. Some designers used sophisticated design methodologies whereas others used a more serendipitous method, that which some of us refer to as “hands-on”. This latter method of being more tactile in the experimental process and allowing new connections to occur and then recognizing the results as potential positive attributes to the design. The key in this more crude design method is discrimination--the ability to recognize the accidental discovery as a positive.

Three designers whom I have come to know through my exhibitions are some of the most talented, innovative people in America, Bob Evans, Erik Buell and Burt Rutan. The three are all very intense designers, each share a high level of enthusiasm with varying personalities. Each has a very private side. Rutan prefers to not give interviews as it takes him away from designing airplanes. These designers are from far different fields. Bob Evans designs swim fins, Erik Buell designs motorcycles, and Burt Rutan designs aircraft. I will use their physical designs to help illustrate their creativity and involvement in dynamic design. The three design for transportation, and their work involves moving objects through air or water. I feel it is their unique personalities that leads to the their innovations. The innovation as evidenced in their work is a result of their enthusiasm, passion, vision, courage and ability to implement a design into the marketplace.

Evans, Buell and Rutan use simple tried and true methods in their design process. It is now a common practice for designers to utilize computers in the design process. All three design and visualize through the use of three dimensional physical models. Evans especially prefers to work with the actual materials in hand. He had tried computer design, but states that he cannot “feel” the weight, nor can he sense the texture and smoothness of the form. Both Rutan and Buell use computers while they are in the design phases of developing a solution. Their use is predominantly in the testing of stress and strain of material, and wind loading on the streamlined forms. Evans and Buell prefer to work with life-size test models, quickly building mock-ups to try human fit and technical function.

As to their similarities, all three are extremely energetic individuals. They are obsessed with their work and their designs. Each designer applies technology and utilizes the latest materials in their work. In fact, they tend to invent technology which makes them leaders in their fields. All are about the same age, early fifties, and late forties. The energy level is so high, in fact, there is very little else in their lives except for their work. Needless to say, the stress levels run high as well. I want to emphasize here individuals, as each one essentially works alone. They do utilize teams of people and specialists in their work, however they tend to be alone in the design process. Each one is driven by their desire to improve upon that which exists. Each is truly an innovator who is making a significant contribution to their respective industries. The individuality, I believe comes from a strong belief in one’s philosophy or ideals. Each is autocratic in their management style. Each one is also a maverick, a person who tends to go against the norm, who dreads sitting in on committees, and who abhors bureaucracy. Each one comes from a one-man shop initially, where design and experimentation was a daily course of activity which lasted well into the night.

Evans, Buell and Rutan are design hybrids. I would call all three artists as well as designers. They are also relentless entrepreneurs. Essentially self-taught in business practices each has an uncanny feel for the market and what could sell. Is this an American trait? I don’t know. However, I do know that in the USA we have many people like these three gambling on a “long shot”. They take risks and experiment with ideas of which others seem to laugh. It is this fortitude, courage, and energy that drives them. In the face of opposition, it seems they get stronger with their beliefs. I believe their passion for the product is equal to their entrepreneurial skills. Being also highly intuitive, they have the ability to make connections and predict outcomes of untried ideas.

They are artists in the sense that their products are things of beauty as well as having superior function. Each man has the final word as to what the object will look like, and each discerns well the balance and proportion weighted against the ultimate function for which it was designed. Similar to the way nature works, these three have the inherent talent to be able to tie all of the disparate elements and processes together to a unified, balanced and beautiful whole.


Bob Evans and the Forcefin

Bob Evans was and still is an accomplished scuba diver. He initially became interested in the beauty of sea-life and thus became an underwater photographer. He is quite an accomplished man with the camera as his photographs have been published widely in books and magazines. Having worked underwater extensively and after logging thousands of dives and expeditions, he became intimately involved with the many difficulties of swimming and maneuvering while attempting to photograph his submariner subjects.

Evans literally grew tired of the constant pushing and pulling of water with the conventional fins as he watched the effortless gliding of the fish around him. He had observed and continues to this day his observation of water as a three-dimensional living substance. He realized the fin cannot be designed with the typical two-dimensional mentality. Another observation was that the faster, more efficient fish had a split tail as a main thrusting feature. All of the fins on the market at the time were flat single fins. As Evans puts it, the flat type is very clumsy and inefficient for swimming and diving. The reinforcement ribs restrict water flow around the fin and increase unwanted drag.

An astute and observant individual, Evans made intuitive connections between man and nature. He found that the highly evolved fish shapes could be adapted to the human form. Humans are “by nature” one of the most inefficient and awkward objects moving in the water. In essence, he wanted to make the human body more fish like, but in a simple manner with the application of an appropriately designed fin.

The basic “Forcefin”, the first model, was physically conceived in 1980, however, the initial concept was realized in the early 1970’s. Evans painfully and diligently evolved the design through many developments of configuration, size and materials. His design methodology was the handling of the design as a dynamic object rather than that of a static one. There was an extensive undertaking of the study of the movements of the foot, ankle, and leg in order to get a good understanding of the dynamic movements of the parts together and separately. An interesting drawing Evans compiled from these leg-movement studies hangs in a prominent place in his studio as a work of art. The innovation was a result of observations of nature in the sea and the application of those observations.

Quickly made of crude materials, many designs were tested, rejected, and refined for quick evaluation. His many configurations were quickly prototyped with chicken-wire and newspaper. His feet would get cuts and bruises as he tirelessly tried concept after concept until he arrived at a shape that worked. Evans would make the molds himself in his shop, pull the product and run to the beach to try a new shape. To this day he still follows the same basic “hands-on” method of design development. Many new materials were tried, tested, and evaluated to seek out the best formula suited for his needs with the fin. He needed a stable compound with the necessary snap and flex that would augment and amplify the movements of the leg and foot.

The latest material being applied to the fins is a two-part liquid polyurethane with a good memory of shape. Evans found this material to be quite forgiving in his unique composite molds. Once the fin was formed and pulled from the mold, he discovered the polyurethane had a chain-molecular bond arrangement that allowed it to be more durable, yet flexible on the flipper ends or as he calls them, the deflecting foils. He found this product while perusing technical journals and saw that it was good for mallet hammers and heavy duty wheels. It was resilient, yet very durable and flexible.

It is the split ends on the fin that are so special. Observing fish with split fins, Evans saw the tremendous maneuverability of these fish. Trying to do a roll underwater with conventional long stiff fins is quite difficult to accomplish. With the shorter Forcefin, and the flexible tips, which work independently of one-another, maneuverability underwater is smooth and easy. Divers who take their first swim with the Evans’ fins first remark that the fin isn’t working because they feel no resistance. Evans is quick to point out that this is the quality he was striving for, an efficiency that makes underwater kicking effortless.

Another unique feature to the Forcefin is its ability to flex and snap. This action-reaction of the polyurethane structure increases the divers thrust. As Evans states, “when in operation, it has power in one direction and then collapses while throwing water behind in the other direction so that it can get back to where you kick against it without strain.” He saw that this action was the same action as what he had seen occur on the fins of a harbor seal on a slow motion video.

The Forcefin is an elegant, organic, fluid-formed device that becomes a natural extension of the human leg. Looking rather strange in our dry conditions walking about on the pier, once in the water the beauty of the design is immediately apparent and functionally is better and more efficient than any other fin on the market. Other models followed as the design became more widely accepted. He now has the “Beaver”, the “Rip Force”, the “Tan Delta” and the most advanced, the “Pro Model” with adjustable “winglets”.

The Adustable Model Forcefin is an adjustable fin to suit the diving and kicking preferences of the diver. Two, independent, small winglets are attached to either side of the fin. These are mounted with hex-head bolts to allow for adjustment in the field. A diver can increase thrust of the stroke by moving these winglets in or out dependent on the performance desired.

Recently, the US Department of the Navy conducted an exhaustive test of many diving fins. Bob Evans' Forcefins came out on top in the tests. The tests concluded that divers using the Forcefin used less oxygen while active in diving than with any other design. Interestingly enough, the elite Navy Seals teams use the Forcefin as further proof of their superiority as a dive fin. “Eventually,” as Evans states, “all fins will be made this way.”

The Forcefin is continuing to catch on. The sales have increased to such a high level, Evans has to consider now the future of his small company and where he wants to go with it. His desire is to design newer fins and try new technologies, but at present the pressure of meeting the tremendous consumer demand for his superior product is taking most of his time.


Erik Buell and the Buell Motorcycle

Erik Buell was and still is an avid motorcyclist. It was at one point in his life he wanted either to be a musician or a motorcycle racer. He lived on a farm during his formative years and loved horses and motorcycles. His first motorcycle was a Honda “step-thru” 50cc. Once a potent racer on the circuit, Buell became very concerned that there weren’t any USA motorcycles being raced in the superbike class. Having had training as a mechanical engineer in Pennsylvania, Buell travelled to Milwaukee, and to the heart-center of American motorcycling, the Harley-Davidson company. There, in 1979, he joined HD and made significant achievements in innovation by getting the company several patents in suspension technology and design. His air-assisted anti-dive mechanism incorporated in his Harley-Davidson FXRT Sport Glide of 1984 and work on the FLT model gained him much recognition far and wide for their engineering as well as styling advancements.

He approached the high level management at Harley-Davidson asking for a chance to work on a new sport motorcycle concept he had been entertaining during his spare time. The grand idea he had did not sing music to the ears of the company executives, and Buell found himself quitting a good job and going home to his modest shop in his garage.

This is the place where much innovation in design is born in the USA---the back yard garage. There, with a few dollars to his name he began the project that would change his life and the lives of many others. From his perspective as a motorcycle racer, he drew out rough specs as to what his ideal sport motorcycle would be. Light weight, aerodynamic, rigid frame, short wheel base, and good looks. He started welding and building, first alone, then with just a few assistants.

Simplicity is the common factor in all Buell designs. Buell had been a motorcycle mechanic while attending engineering school. Working “hands-on” in a multi-brand shop, Buell recognized early that most motorcycles are too complicated and have too many parts. He also observed that many of the motorcycles were difficult to maintain and tune. A key requirement was to let the rider ride the motorcycle, instead of worrying about valve timing and tune-ups. His motorcycle was also going to be lighter, more efficient, user friendly and easy to maintain.

Buell uses simple laws of physics and engineering artfully applied for his purposes. Not a follower of tradition, he supplants the common stand-by application of exotic materials with common sense. He notes that many other designers over complicate the design, then to make it practical, they use very expensive, exotic, lightweight materials. Such is the argument of the single front brake rotor featured on all Buells. Buell maintains one large rotor is enough and keeps the unsprung weight low. Other designers overburden the front wheel with two rotors, then have to shave weight with material substitutions to make it work.

Buell bought the Barton engine in England, which had become available, an advanced, two-stroke square four racing engine of 750cc. He enclosed this special engine in his first perimeter geodesic chrome-moly frame. A fully enclosed fairing was added for maximum aerodynamic efficiency. Thus the first Buell motorcycle was born in 1983, the Buell RW 750. This was the first fully enclosed high performance motorcycle. Full body work had been seen before on motorcycles, but not to the extent in which Buell incorporated it, especially on a consumer street machine. His intent was to race this machine, however the AMA Formula One racing rules changed and he had to abandon the Barton project. The positive outcome of this project were the precedents for future projects, the fully enclosed fairing, stable geodesic space frame and simplicity of design.

The first successful consumer-available project to come from his garage in 1987 was the Buell RR1000. Fully enclosed with body work, this machine was and still is one of the best performers in the wind tunnel. The RR1000 incorporated the HD XR1000cc Sportster motor. This motor was the most powerful HD ever produced. Buell took this opportunity because nobody including HD wanted it. Being in such close proximity to the HD factory and engine plant, Buell had access to the latest engine technology in Milwaukee. He found that Harley had a surplus of unused XR 1000 engines and they were available for Buell to purchase. Buell preferred and still does prefer the Milwaukee in-line engines as it allows him to achieve better cornering characteristics, narrow body, as well as mass centralization. Innovative in this model was his perimeter geodesic space frame surrounding the motor, rear suspension components slung under the motorcycle, and one-single massive front six piston brake. The space frame was not as new of an idea, however the single front brake configuration and the underslung suspension got Buell noticed in the world of Motorcycles.

Most of the public’s response to this machine was mixed. It had superior performance but others did not care for the bulbous body work, which Buell believed was quite necessary for a high-performance road machine. He achieved simplicity in the components he selected and the basic configuration. His subsequent model, the RS 1200 of 1989 lost some of its body work as a response to public opinions. However, the other Buell signature components remained on this machine. In 1991 he introduced the inverted front fork to the first production motorcycle. Buell began to sell his products well in many countries especially Japan. His small factory with a very limited number of specialists produced about 500 hand-built machines between 1988 and 1993.

In 1991 Buell was asked to design a “mountain bicycle” with suspension for the Paramount Bicycle Company in Waterford, Wisconsin USA. His signature under-frame suspension was utilized in the bicycle in a similar way he applied it in the motorcycle. A “D” shaped swing arm kept the rider level while pedaling and was a breakthrough in bicycle suspension technology. The rear suspension featured a full 4”, 102mm of travel.

Buell says he’s autocratic and strong-minded in his dealings with subordinates. He does his research, and when he gets his mind on an idea, he is relentless to follow it through to the last detail. Whether it is successful, or not, he is untiring in making sure the project is complete. He is heavily influenced by automobile designs of the yesteryear, unique styling excites the mind of this designer. His design mentor is Raymond Loewy and his favorite car design is the Studebaker Hawk.

Ironically, in 1993, almost a decade after Buell left Harley-Davidson, the motor company came knocking on Buell’s door with an offer to fund his projects. In return Buell would give them a substantial share of stock in his company. The timing of this offer was perfect as Buell needed the financial support at this critical stage. This new relationship with the large Milwaukee company with its distribution network in place allowed Buell to finally fulfill a dream to get Buell motorcycles out to the public in numbers never before seen. During this period Buell produced the S2 Thunderbolt. Following and still in production is the S1 Lightning, the S3 Thunderbolt and the M2 Cyclone. All share the same perimeter space frame and similar suspension and brake units. They are the lightest motorcycles in their class of 1200 cc motors and have the shortest wheelbase.

Buell reworked the conventional HD factory Sportster motor, and squeezed more horsepower out of it than ever expected. For a street-legal machine, Buell was able to increase performance to 101hp and make the S1 one of the quickest machines off the line. He accomplished this by suggesting a shaved flywheel and new head and cam configurations. The free-breathing air box coupled with a non-restrictive exhaust propelled the Sportster engine into the high performance category.

Buell’s fledgling company is still in its infancy and he still believes in innovation and technology above all else. Buell is satisfied that his “David and Goliath” fight is becoming in his favor. Erik Buell truly is a garage-born, lone missionary who is changing the way the world looks at, and rides motorcycles.


Burt Rutan and the Scaled Composites Company

As an eleven year-old boy, Burt Rutan’s room was a workshop for model airplanes. As his famous pilot-brother Dick Rutan puts it, “Burt was a little different, if I were the wild greaser, Burt was the pimply science kid, obsessed with airplanes.” As a youngster, he won several model airplane competitions with models of his own design. His physics course in high school was a pivotal point in his life where he saw scientific principles that could have practical uses. Later these principles, enhanced by his intuition, would be applied in his involvement with aviation. His mentors are the great Kelly Johnson of Lockheed and Wernher von Braun, the rocket pioneer.

Rutan has little time for anything other than designing airplanes. His wry sense of humor is evident whenever talking about existing norms in aviation design or construction. He says he was dissatisfied and bored with the direction he saw aviation going, and he wanted to change that course.

The airplanes he designed are easily identified at air shows and airports, most share the front canard wing configuration and the so-called “pusher” prop. The canard is a small wing located at the front of the fuselage. The pusher prop is a propeller pushing back, behind the airplane. Essentially the canard improves the handling and decreases the possibility of stalls. The pusher prop helps keep a smooth airflow over the plane. It is interesting to note that the Wright brothers’ planes had these features as well. Generally dropped by the aviation industry, Rutan reused this early aviation innovation to his advantage in his unique aircraft designs. In the early 1970’s Rutan got noticed for three little home-built airplanes he designed and built which revolutionized the industry. His planes the VariEze and LongEz and VariViggen were years ahead of the typical boxy “stick and fabric” home built aircraft of the time.

With new materials and new wing and fuselage configurations, Rutan was able to make any shape possible and cut much of the unwanted structural weight. As a result, the planes were faster, smoother, longer range, safer and easier to build. Rutan was able to sustain himself by starting the Rutan Aircraft Factory and selling plans and supporting kit-builders around the world. Sadly, because of the extreme product-liability concerns in the USA, Rutan had to halt his production of plans for his home-building enthusiasts. The threat of lawsuits on his experimental designs put a halt very quickly on his small aviation firm and its related support industry.

That negativism did not stop Rutan. He created a new company called Scaled Composites and became a consultant to the aviation industry. Rutan would sequester himself in his hangar in the Mohave Desert, and on speculation, unveil new designs in quick succession. Now companies, with the belief in innovation in design, consult Rutan and incorporate many of his ideas into their planes. One such example is the Beechcraft Starship. This is an elegant business class plane with two rear engines, canard and swept back wings and is similar to the early VariEz but much larger. Also made of composite materials this plane was and is a top performer. Market acceptance however, had been slower than expected.

Rutan’s most famous and challenging venture was the design of the Voyager. This was an aircraft that had to fly around the world non-stop and without refueling. This was a challenge indeed, one which no large corporation or military organization had ever accomplished. This feat was considered the “last-first” in aviation history. Using the basic aerodynamic formula of thrust, weight and drag, Rutan calculated what it would take to carry all of the fuel necessary for such a flight. The plane weighed 4,400kg empty, 22,000kg loaded and the amount of fuel needed was that of a fully loaded tanker truck, about 5,000 liters. The fuel accounted for 72% of the total weight of the plane. A unique configuration was arrived at with two motors, one pushing and one pulling in-line with the fuselage. Both motors were used during the take-off climb, after that only one was needed for level flight.

Rutan’s brother Dick and friend Jeana Yeager were to pilot this experimental untried design. Rutan put his reputation and the lives of loved ones on the line with this project. The unusual design consisted of carbon-fiber composite technology. The plane was hand built by the pilots and an army of friends and volunteers. Technology had to be invented on the spot as the plane was completed. With a modest budget, the plane was then ready for the world flight.

In 1986, the pilots were in the air for nine days straight and completed their mission after logging more than 42,000 kilometers. Burt Rutan was now a famous aviation designer with a very reliable reputation. He received the Presidential Citizen’s Medal of Honor.

Many new projects and challenges followed: including an ultra light car design for GM and a racing plane. The Pond racer was a radical new twin-engine entry in the unlimited racing class in Reno, Nevada. Recently, his asymmetrical designs for aircraft have become more apparent at aviation conventions. These modified configurations coupled with new technology of engines and lightweight composites, resulted in breakthroughs in modern aviation as seen in the Rutan designs. One very new design of his, the “Boomerang” is an example of the asymmetrical twin-engine design. Built for himself, it is a test-bed for new technology, new materials and new avionics. This was seen for the first time in Oshkosh, Wisconsin in 1996.

Asymmetry in aviation design is rare. Rutan observed that twin engine propeller planes are dynamically unbalanced even though they appear balanced symmetrically. Through the process of elimination, he arrived at a solution that provided dynamic stability through an unconventional asymmetrical design. He also wanted a safer twin engine plane that would have stable one engine on, one engine off, operating performance. He built this in his spare time in the “back room” at Scaled Composites and is experimenting with it until he finds a marketable outlet for its features. It is this speculative design nature of Rutan that is unique.

The most recent project, the Proteus is a twin-engine high-altitude aircraft capable of many tasks. Unique in its structural configuration and modularity, is an extremely versatile aircraft. It is an all-composite canard design, typical of Rutan. With “HALO” (high altitude, long operation) the plane can loiter in the air for up to 18 hours and at an altitude of 96000 km. Telecommunications signals can be bounced off the pod slung under the aircraft for a fraction of the cost of other planes like the U2 or satellites. The plane is also capable of carrying orbital and sub-orbital boosters to make space access more affordable. It is this design that will take Rutan into space. His dream of making space flight affordable is becoming reality. With the Proteus, Rutan has plans to win the “X Prize” competition. This is a challenge to see who can become the first “citizen” to design, build and fly in the first non-commercial, non-military manned space vehicle. The award is $10 million US dollars to the first team to accomplish this feat.


In Conclusion

These three men accomplished remarkable feats with little support. They are the pioneers of our time. They are all competitive, dedicated and have persistent self-motivation. Another common trait is their ability to follow-through and implement their designs into reality. They were alone with their unconventional ideas and the challenge to succeed helped them move ahead. With their unique vision and stamina, they beat the odds against them for their success. These men, single-handedly against huge multi-national corporations and research and development departments of the industry were successful with their dreams. Harley-Davidson Inc. couldn’t do it, Buell did. US Divers Corporation couldn’t do it, Evans did. Boeing Corporation couldn’t do it, Rutan did.

The function of the products presented is remarkable in addition to their having unique inherent visible beauty. In conclusion, using the words of all three of these men, “Just go ride the motorcycle, just go swim with the fins, just go fly the airplane.” The proof of good design is in the look and most importantly the performance. I assure you that if you do take this simple advice you will find yourself amazingly impressed with the advanced creations of these talented men.




Sources:

Angelucci, Enzo, The Rand McNally Encyclopedia of Military Aircraft, 1914-1980. (New York, 1980) 239, 314, 325.

Buzzelli, Buzz Harley-Davidson Sportster Performance Handbook. (Oceola, Wisconsin, USA, Motorbooks, International, 1992) 64, 65, 151, 178.

Chaikin, Andrew, Air and Space. (New York, National Air and Space Museum, Smithsonian Institution, Little Brown, 1997) 282

Cox, Jack, Sport Aviation magazine. “Boomerang” (Oshkosh, Wisconsin, USA, October 1996) 19-28.

Greenwood, John, Milestones of Aviation. (New York, Macmillan Publishing. Smithsonian Institution Publication. 1989) 75-77.

Hallion, Richard P., Designers and Test Pilots. (Alexandria, Virginia, USA, Time-Life Books, 1983) 167

Kostman, Chris, Aqua Corps 13 Magazine. “Fin Doktor” (Key West Florida, USA. Feb/Mar 1996) 62-72

Sucher, Harry V., Harley-Davidson, The Milwaukee Marvel. (4th Edition. England, Haynes Publications 1992) 280, 312, 313, 327.

Wirth, Harry J., Biographical Questions sent to the designers for this writing and personal conversations with Bob Evans and Erik Buell. Conversations with Burt Rutan through Kelly Hall. April 1998

Wirth, Harry J., Personal notes from previous design exhibitions. Notes from the Experimental Aircraft Association Conventions, Oshkosh, Wisconsin USA, Other personal notes from meetings and interviews. 1993-1998.

Wirth, Harry J., The Art of Design 2. (Exhibition Catalogue, Salem, Wisconsin, USA 1993)

Wolff, Anthony, OMNI Magazine. “Rare Bird” (New York, July 1980) 100-104

Yeager, Jeana and Rutan, Dick, Voyager. (New York, USA, Random House)



Web page addresses:

Bob Evans, www.forcefin.com
Erik Buell, www.buell.com
Burt Rutan, www.scaled.com
Harry J. Wirth, www.harrywirth.com


Correspondence:

Prof. Harry J. Wirth
Associate Professor of Design
School of Art
Northern Illinois University
c/o
The Crow’s Nest Studio
4515 256 Ave.
Salem, WI USA 53168

Phone: 262.210.1183
email: hwirth@tds.net

Happy Holidays!

Tis the season when we all celebrate the Holidays. We wish a warm and healthy December and a prosperous New Year to all. At Force Fin we are kicking off a 30% discount on over 12 Force Fin models until January 13th. So you could be looking at The New Year gift to start the year right. We have even put on the Flying Force as part of the Program.


Safe diving, fair winds and following seas,
Bob Evans

My Favorite Fitness swimming Fin

I have used the Adjustable Slim Fin for over a decade , but it was the last 10 years that I have used it 5 days a week in the Los Banos pool to start my mornings. It is called the Adjustable Slim Fin because it adjusts over the bridge of your foot to your size or to the varying foot sizes and equipment combos that are found in team settings and in different environments.



Similar to all of the models in the Adjustable Force Fin line, once the fin is adjusted to your foot- there is no more adjustments. Now if I wanted to use my same fins in the Ocean and wear a aqua sock, booty ect I could adjust the foot pocket to my new foot wear. With a bungie heel strap standard, the Adjustable Slim Fin is my Favorite Fitness swimming fin.