SEAWORTHY

FIT OR SAFE TO TRAVEL AT SEA
(Merriam-Webster)

SPEED

VS

STABILITY

A FINE TUNED BALANCE



SEAWORTHINESS IS NOT A FORGOTTEN FACTOR

Learn why not all hull designs are created equal. Speed and economy come with sacrifice and can ignore the ultimate factor of safety.



Detailing the mold for the Bahama 41

Throughout the evolution of modern FRP (Fiber-Reinforced Pressure) vessels, there has been a tendency for boat designers and builders to concentrate on hull shapes that produce ever faster speeds. Unfortunately, some of the very same features that reduce drag, such as hull steps, also have a tendency to significantly reduce directional stability and efficiency in various sea conditions.

Seakeeping: The established limits for the vessel’s responses. "These are based on the vessel motions and accelerations experienced and include comfort criteria and performance based values such as involuntary speed reduction and observable phenomenon such as bow immersion." (St. Denis, 1976)

Bahama Boat Works considers safety at sea to be its FIRST design criteria, not an afterthought! Each of its hull forms was computer designed based on data collected from over 80 years of documented planing hull research and application. Hydrodynamic efficiency is achieved by the initial design shape combined with maintaining incredibly close dimensional tolerances from the digital design program, thru the CNC cut model, to the lowest shrink tooling system available for the mold making process.





Bahama Boat Works hulls are as symmetrical and fair as modern technology will allow. Natural dynamic directional stability in all seaways - whether head seas, cross seas, or following seas - has been of primary consideration to their design team. Likewise, questions of ready pitch and roll trim range were treated with the utmost importance.

As a result, every Bahama Boat Works center console boat hull offers unusually predictable stability, control and comfort - not only when seas are flat, but most importantly when conditions turn dangerous. Shooting an inlet in a large following sea becomes a pleasantly reassuring experience, not an unpredictable scary thrill ride. This is the result of hull shapes that were created and engineered to work as well at slow speeds as they do at high speeds. Their seakeeping ability makes them unusually seaworthy. At Bahama Boat Works seaworthiness is not a forgotten factor and your safety is not an afterthought!

We invite you for a trial run, and let the ride speak for itself.



Lets explore even more of the key factors at play...

ENGINEERING FACTORS

Let's consider some of the engineering factors that are extremely critical in the manufacturing process of these larger “super-center-console” boats, and why?

One of the first and foremost considerations is the structural integrity of the hull design itself.

There are many methods used in the marine industry, but not all of these produce a well-designed hull that will not only ride smooth and dry but support these increased LOA boats upwards of 40 feet in length, yet maintaining a reasonable weight to size ratio that does not require additional expense in powering a boat that is too heavy, or so light that it reduces the overall ride and comfort and still maximizes deck space.

The strength and structural integrity of stringers, bulk heads and the integration of the liner and cap can also mean the difference between unnecessary vibrations and stress cracking in critical locations over time that can be costly to repair and reduce the value of the boat in a short period of time.

Then you have the balance concerns, especially when it comes to console, power generation and gas tank placement and installation methods.

Let’s address these engineering factors.

TRUE MOLDED HULLS

Fiber Reinforced Polymer (FRP) composite boats have been in production for over 70 years. During that time period, much information has been collected on the best engineering and fabrication practices to follow. As the hull sizes for center console boats have increased in recent years, proper engineering has become ever more important. Bahama Boat Works has employed the lessons learned by the industry to manufacture the most structurally sound and durable center console vessels possible with current technology.

FRP CHARACTERISTICS

It is extremely important to acknowledge that fiber reinforced polymer composites are non-isotropic in nature. That is to say that they do not display the same physical characteristics in all directions like metals do. Instead, they are inherently highly directional. While the resin matrix used will behave in an isotropic manner, the fiber reinforcements that are held in column by the cured resin will distribute stress in a linear fashion – kind of like how spokes on a bicycle wheel work. “Load paths” can be accurately defined and positioned. When FRP composites are simply considered to be isotropic, the considerable potential benefits provided by the reinforcing fibers will most likely not be enjoyed.

INTEGRATED STRUCTURE

The advent of monocoque construction techniques revolutionized both the aircraft and automobile industries. The term monocoque means that the skins of a structure assume all or most of the loads that might be applied. For example, in the automobile industry, “unibody construction” yielded stiffer, lighter, more durable and safer structures than the older “body on frame” techniques. Load energies could be more widely distributed. Structural strength is defined by the amount of applied energy that can be distributed over the largest area possible. When a structure is “integrated”, the increase in area produces a great benefit in strength, if for no other reason than the increased surface area. When equal consideration is given to both the shapes of a structure and the load paths provided by the materials used to fabricate it, a synergy is produced that can yield a highly durable result.

THE END RESULT

The Bahama hull is engineered with these factors in mind; to provide the most elegant solution possible for an unusually safe and durable vessel. The construction technique and the painful attention to every detail, although quite technical, is as follows:

  • Using Bahama Boat Works’ True Molded technique, after being gel-coated and skinned with vinylester resin and all hand laid chopped strand mat applied, all hulls are vacuumed to their mold for the entire three week, 24 hour per day period of their construction. While other boat companies will remove a partially finished hull from its mold in order to make room for the next order in their production cycle, Bahama Boat Works resists this temptation in order to produce a hull with the highest fidelity to its original CAD/CAM model. All internal structure has been completed and cured before the interior liner is applied; then the liner is ALSO vacuumed into place. Only after both hull and liner are fully cured is the hull vacuum on the hull mold released and the completely integrated structure removed from its mold. It’s not the fastest process, but it is absolutely the BEST process!
  • After initial skinning with hand laid chopped strand mat, hull bottoms receive two layers of biaxial fiberglass in their spray strakes before special purpose-engineered elastomeric putty is used to fill them. This allows the following bottom laminations – six alternating layers of 0-90 & 45-0-45 biax on the sides and nine alternating layers in the center – to provide straight load paths across the bottom. From the chines upward, the topsides feature three layers of 1 ½ oz. hand laid chopped strand mat, 1708 biax, 1” Corecell foam vacuumed in place and 3610 quadrax fiberglass fabric.
  • All five stringers employed in the hull are solid fiberglass laminates, produced by four layers of 3610 quadrax in a vinylester resin matrix. This fabrication technique produces stringer reinforcement that does not produce hard points in the bottom when they are applied, thus eliminating the “hinge effect” of glassing non-flexible frames to the craft’s bottom.


SETTING THE STANDARD OTHERS ASPIRE TO



DESIGN & ENGINEERING

DESIGN & ENGINEERING

At Bahama Boat Works, the prime directive for the design and engineering of all of the electrical and mechanical systems necessary for the operation of the vessel has always been durability and ease of access – not necessarily the ease of manufacturing. Each element is analyzed not only for its initial quality and efficiency of function, but also for ease of access throughout the life of the vessel. We feel that nothing can be more aggravating than discovering that a component cannot be accessed and worked on. To this end, we spend extra time putting ourselves in the place of the owner or mechanic when maintenance or repair eventually becomes necessary. The results of this predictive analysis are manifested in lovely, logical systems layouts with intuitively understandable means of access.

DEPENDABLE PERFORMANCE

DEPENDABLE PERFORMANCE

We believe that the use of first quality components is the most direct route to efficient and dependable performance. At Bahama Boatworks each component is analyzed for its initial quality and established history of performance and durability, and if it doesn't measure up, we design and manufacture it ourselves. It’s not that we believe that “cost is no object”. We do strongly feel that when cost is necessary for the quality required, then cost should not be design prohibitive. This is how we achieve our industry standards of dependability – by NOT taking shortcuts.

TRUSTED RELIABILITY

TRUSTED RELIABILITY

When insightful design and engineering are combined with dependable components, the result is ease of maintenance, reliability of function – reliability that can be trusted no matter how far off shore you are or what the conditions of operation might be. Trust must be earned, and the best measure of trust in our vessels can be found in conversations with our customers. They are our finest advocates!