Patent Application
20240025516
The present invention generally relates to a surfboard. More particularly, the present invention pertains to a layup system and method for constructing a surfboard.
It is generally understood that the construction of surfboards has evolved with the advent of newer materials. For example, foam core has replaced wooden boards and the use of epoxy has largely replaced the use of polyester resins. However, currently, essentially all surfboards manufactured today use fiberglass fabric. While there are many fibers that are stronger and stiffer than glass fibers, for various reasons, the use of these higher performance fibers, such as carbon, aramid, and the like, has not been accepted into the surfboard industry, and/or have not been utilized in industry in manners providing sturdy, reliable, high-performing, and aesthetically pleasing products.
Some of the potential drawbacks of the use of higher performance fiber fabrics is the expense and the specialized care required to layup the fabric on the highly contoured foam blank and the finishing of the cured layup. Unfortunately, the largest drawback may be that a surfboard made with higher performance fiber fabric is not acceptable to surfers because the resulting surfboard is too stiff. That is, surfers desire a surfboard that has a certain degree of flexibility and can develop a spring tension that the surfer can create and release as a wave is surfed.
Accordingly, it is desirable to provide a method and system capable of overcoming the disadvantages described herein at least to some extent.
The foregoing needs are met, to a great extent, by the present invention, wherein in one respect a system and method is provided that in some embodiments generates a surfboard with a carbon fiber fabric and a sufficient amount of flexibility to facilitate proper function of the surfboard.
An embodiment of the present invention pertains to a surfboard. The surfboard includes a rocker defining a bottom surface of the surfboard, a deck defining a top surface of the surfboard, and a pair of rails disposed on opposite sides of the surfboard. Each rail defines a side surface of the surfboard and connecting the rocker to the deck. A pair of edges is defined by an interface between the rocker and the corresponding rail. A tip is disposed at a front of the surfboard. A tail is disposed at a rear of the surfboard. The surfboard includes a first layer and a second layer. The first layer is defined by epoxy impregnated fiber reinforcement fabric configured to cover the rocker and the rails and wherein the first layer extends onto the deck at a middle portion of the surfboard and tapers toward the tip and tail so that the first layer does not extend onto the deck at the tip and the tail. The second layer is defined by epoxy impregnated fiber reinforcement fabric configured to cover the deck and wherein the second layer extends to cover the rails at a middle portion of the surfboard and tapers toward the tip and tail so that the second layer covers less than half of the rails at the tip and the tail.
Another embodiment of the present invention pertains to a method of fabricating a surfboard. In the method, a first layer is applied to a foam blank, the foam blank having: a rocker defining a bottom surface of the foam blank; a deck defining a top surface of the foam blank; a pair of rails disposed on opposite sides of the foam blank where each rail defines a side surface of the foam blank and connecting the rocker to the deck; a pair of edges defined by an interface between the rocker and the corresponding rail; a tip disposed at a front of the foam blank; and a tail disposed at a rear of the foam blank, wherein first layer being defined by epoxy impregnated fiber reinforcement fabric configured to cover the rocker and the rails and wherein the first layer extends onto the deck at a middle portion of the foam blank and tapers toward the tip and tail so that the first layer does not extend onto the deck at the tip and the tail. A second layer is applied to the foam blank. The second layer is defined by epoxy impregnated fiber reinforcement fabric configured to cover the deck and wherein the second layer extends to cover the rails at the middle portion of the foam blank and tapers toward the tip and tail so that the second layer covers less than half of the rails at the tip and the tail.
There has thus been outlined, rather broadly, certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
The present invention provides an improved carbon fiber surfboard, a layup system for the surfboard, and a method of applying the layup. In some embodiments, the invention provides a carbon fiber surfboard with improved flexibility and ability to develop spring tension. This surfboard includes the improved strength and resistance to breakage as a result of the carbon fiber fabric and also includes a controlled amount of flexibility configured to provide the ability to develop spring tension. For the purposes of this disclosure, the phrase, ‘ability to develop spring tension’ and derivations thereof, refer to the surfboard acting like a spring and the ability to flex under load and then return to the original shape quickly after the load is reduced. For the surfer, this ability of the surfboard is described as, ‘lively’, ‘dynamic’, and the like.
The layup system is configured to provide the characteristics to the surfboard by controlling an amount of overlap in the layers of carbon fiber fabric. Other benefits of the layup system may include improved fidelity of the shape of a foam core translating through to the finished shape. That is, the layup facilitates sharp bends in the carbon fiber fabric.
Advantages of various embodiments of the invention include, for example: (1) a carbon fiber surfboard with improved flexibility configured to provide the ability to develop spring tension; (2) improved fidelity of the shape of a foam core translating through to the finished shape; (3) reduced post-curing; and (4) reduced wastage of vacuum bagging supplies.
The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. As shown in
If included, the optional logo 24 may include a printed design and/or text on a transparent sheet stock such as rice paper or the like.
In a particular example, the layer 40 includes a 3K 94.8 grams/meter2 (“g/m2”) (4 oz/square yard) plain weave carbon fiber fabric. The term, “3K” refers to the number (3,000) of filaments per tow of the weave. In other examples, the layer 40 may include 1K-12K carbon fabric in twill, tri-axial, or other weave patterns and having weights from about 23.7 g/m2 to about 284.4 g/m2. In yet other examples, the layer 40 may include a mixed fiber fabric such as carbon/aramid. In other alternative or complementary embodiments, other suitable material specifications can be used. Suitable material specifications can, in embodiments, avoid over-stiffening and/or add dampening to the board.
Of note, while described as carbon fiber fabric, the layer 40 may include any suitable fiber reinforcement fabric or other such material. While some embodiment described herein are particularly applicable to the use of carbon fiber, aramid fibers, and other high strength/low stretch material, in other examples, higher stretch material such as fiberglass, polypropylene, and the like may also benefit from the controlled modulation of the flexibility of the surfboard 10.
While not disposed on the layer 40,
If the optional logo 24 is included, an optional protective layer 56 may be disposed on top of the logo 24. The protective layer 56 may include any material or coating suitable for reducing damage to the logo 24. In a particular example the protective layer 56 may include a 47.4 g/m2 (2 oz/yrd2) fiberglass fabric. In alternative or complementary embodiments, different specification material may be used as a protective layer 56 (or other elements of surfboard 10).
Of note, while described as carbon fiber fabric, the layer 60 may include any suitable material. While some embodiment described herein are particularly applicable to the use of carbon fiber, aramid fibers, and other high strength/low stretch material, in other examples, higher stretch material such as fiberglass, polypropylene, and the like may also benefit from the controlled modulation of the flexibility of the surfboard 10.
Optionally, the profile 64 may also be used to cut an optional denting cloth 64D. If included, the denting cloth 64D is configured to reduce denting of the deck 30. In some examples, the denting cloth 64D may include a layer of fiberglass cloth. polypropylene cloth, or the like. While not disposed on the layer 60,
If the optional logo 24 is included, the optional protective layer 56 may be disposed on top of the logo 24. The protective layer 56 may include any material or coating suitable for reducing damage to the logo 24. In a particular example the protective layer 56 may include a 47.4 g/m2 (2 oz/yrd2) fiberglass fabric. In other alternative or complementary embodiments, other suitable material specifications can be used.
In operation, the vacuum pump 74 draws air from the vacuum bag 70 and atmospheric pressure presses the vacuum bag 70 unto the layup 72 to compress and consolidate elements of the layup 72 such as the layer 40 and/or the layer 60. As described herein, the layer 40 and/or the layer 60 are saturated with epoxy resin and a catalyst during the method of constructing the layup 72 and the vacuum compression is maintained until the epoxy has cured. Vacuum compression can be maintained at a constant pressure, or vacuum compression can be maintained at varying pressure during curing. In embodiments, vacuum pressure can be approximately 25 kPa. Alternative embodiments can utilize static or variable vacuum pressure during curing less than 25 kPa, for example, 15 kPa or 20 kPa. In embodiments, more than 25 kPa can be utilized during curing. In embodiments, temperature control during application and/or curing of the epoxy can be used during the process to facilitate saturation, curing, or other parameters. In a particular embodiment, the temperature during application and/or curing may be maintained at substantially 75 degrees Fahrenheit. In an alternative or complementary embodiment, the temperature during application and/or curing may be maintained at target temperature plus or minus a threshold. In complementary embodiments, the threshold can be one degree, five degrees, or ten degrees Fahrenheit, or another temperature difference depending on the epoxy and/or materials in contact with the epoxy during its application or curing. In additional alternative or complementary embodiments, humidity can be controlled during application and/or curing of the epoxy. In various embodiments, humidity can be maintained below 50 percent, 40 percent, 30 percent, 20 percent, or another humidity level depending on the epoxy and/or materials in contact with the epoxy during its application or curing. In embodiments, the temperature and/or humidity can be changed during application and/or curing. For example, the temperature may be decreased following application, or increased following application; the humidity may be decreased during application, or increased following application. Temperature and/or humidity may both be changed together or independently, and may be changed after curing has started following a period of time. In embodiments, the period of time may be 1 minute, 5 minutes, 10 minutes, or other periods of time based on the epoxy and/or materials in contact with the epoxy during its application or curing.
The peel ply 78 is configured to impart a texture on the cured epoxy so that subsequent epoxy coating will adhere to the surface. Additionally, the peel ply 78 may facilitate absorbing excess epoxy from the carbon fiber fabric. More particularly, the peel ply 78 plain weave Nylon having a weight of about 23.7 g/m2 to about 47.4 g/m2. In other alternative or complementary embodiments, other suitable material specifications can be used.
The release film 80 is configured to form a barrier between the curing epoxy and the breather cloth 82. Typically in surf board manufacturing, release films are to 0.15 mm or more and typical release films are perforated. However, the release film 80 is thinner to facilitate producing a higher fidelity finished surface. That is because a thicker release film resists bending along a tight curvature or edge such as the edge 18. This tendency causes a rounding of the edge 18 and a loss of fidelity between the shape of the foam blank 76 and the finished surface. In addition, because release films are a film rather than a woven fabric, they tend to form wrinkles or creases when conforming to surfaces that are curved in more than one direction, such as on the rail 32 near the tip 14 and/or tail 16 of the surfboard. These downsides of thicker release films impact both the performance and aesthetics of the finished surfboard 10. It is an added advantage that the thinner release film 80 reduces wrinkles because it is easier to stretch and, if a wrinkle does form, the thinness of the release film 80 imprints a smaller ridge than a thicker release film. It is another advantage of the non-porous nature of the release film that the breather cloth 82 is not fouled with epoxy and so can be re-used rather than discarded. In a particular example, the release film 80 is 0.00787 mm (0.31 mil) high density polyethylene. In other alternative or complementary embodiments, other suitable material specifications or thicknesses can be used.
The breather cloth 82 is a spun felt cloth configured to facilitate drawing a vacuum within the vacuum bag 70.
In this manner, the rigidity of the rail 32 is modulated along the length of the surfboard 10 so that the ability to develop spring tension is controlled along the length of the surfboard 10. Without being confined to a particular set of scientific principles, the control of the ability to develop spring tension along the length of the surfboard 10 enables the entire length of the surfboard to act as a spring. In contrast, a surfboard that lacks the modulation of the rigidity of the rail 32 might flex at a point of loading but that flex would not translate outward along the surfboard from the point of loading.
At step 106, the layer 40 is applied to the foam blank 76. For example, the layer 40 may be generated by cutting a carbon fiber fabric stock along the cut line 48. In some examples, this cut line 48 may be cut via a CNC cutter. In other examples, the cut line 48 may be determined by draping the carbon fiber fabric stock on the rocker 12 and cutting the cut line 48 while making allowances to generate the overlap 84 at the middle portion of the surfboard 10, the overlap 88 at the tip portion of the surfboard 10, and the overlap 90 at the tail portion of the surfboard 10.
The peel ply 78, release film 80, breather cloth 82 may be cut or otherwise readied for use. Sufficient epoxy may be mixed with hardener. The optional fin box re-enforcement layers 54 may be saturated with epoxy. The layer 40 may be applied, wetted out, and any excess epoxy removed. This ‘wetting out’ procedure is also described as epoxy impregnation and is used to describe the process of filling the weave of the fiber reinforcing fabric with epoxy. As is to be understood, care is taken to have the layer 40 smoothly follow the contours of the foam blank 76. If the logo 24 is to be applied, it is applied over the layer 40, covered with the protective layer 56, wetted out with epoxy and excess epoxy removed. The peel ply 78 is applied, smoothed, and stretched taught. The release film 80 is applied, smoothed, and stretched taught. The breather cloth 82 is applied and any excess gathered and secured.
The layup 72 may be disposed within the vacuum bag 70, the vacuum bag 70 may be sealed, and the vacuum pump 74 may begin to withdraw air from the vacuum bag 70. As air is being drawn from the vacuum bag 70, the vacuum bag 70 can be ‘trained’ by drawing the surface of the vacuum bag 70 disposed over the layer 40 to follow the contour of the rocker 12. Excess of the vacuum bag 70 may be rolled and folded under the layup 72. The layup 72 is allowed to cure at step 108 while under vacuum pressure. Following the curing, any surface imperfections may be removed.
At step 110, the layer 60 is applied to the foam blank 76. For example, the optional dent cloth 64D may be applied, wetted out, smoothed, and excess epoxy removed. The layer 60 may be applied, wetted out, smoothed, and excess epoxy removed. If the logo 24 is to be applied, it is applied over the layer 60, covered with the protective layer 56, wetted out with epoxy and excess epoxy removed. The peel ply 78 is applied, smoothed, and stretched taught. The release film 80 is applied, smoothed, and stretched taught. The breather cloth 82 is applied and any excess gathered and secured.
The layup 72 may be disposed within the vacuum bag 70, the vacuum bag 70 may be sealed, and the vacuum pump 74 may begin to withdraw air from the vacuum bag 70. As air is being drawn from the vacuum bag 70, the vacuum bag 70 can be ‘trained’ by drawing the surface of the vacuum bag 70 disposed over the layer 40 to follow the contour of the deck 30. Excess of the vacuum bag 70 may be rolled and folded under the layup 72. The layup 72 is allowed to cure at step 112 while under vacuum pressure. Following the curing, any surface imperfections may be removed. Similar to the discussed above, temperature and/or humidity may be controlled at least during this step to facilitate application and/or curing. In embodiments, the temperature may be controlled to approximately 75 degrees Fahrenheit. Temperature thresholds and/or temperature changes, as wells as humidity levels and/or humidity changes, can be employed based on the materials, vacuum specification, or other parameters.
At step 114 hot coating is applied to the deck 30. For example, the surfaces of the deck 30 and rails 32 are sanded, and the rocker 12 taped off. Epoxy is applied to the deck 30 and allowed to partially cure. Any pin holes and bubbles are removed. A second coating of epoxy is applied and allowed to fully cure. In embodiments, the pin holes or other portions can be cleaned or excess material can be removed between a first and second coating, or after a second coating.
At step 116, a hole for the leash plug 34 is drilled.
At step 118 hot coating is applied to the rocker 12. For example, the surface of the rocker 12 is sanded, and the rail 32 taped off. Epoxy is applied to the rocker 12 and allowed to partially cure. Any pin holes and bubbles are removed. A second coating of epoxy is applied and allowed to fully cure. Prior to or immediately after the first and/or second hot coating (or other coating in alternative embodiments), the tail of the surfboard (or other portions) can be laid level to prevent any coating from running or building up in or on any portion of the board (i.e., the tail) and prevent the hard edge from draining. In embodiments, a tape edge can be formed around the tail of the surfboard (or other portions) to raise the edge where epoxy runs, assisting with forming or strengthening the hard edge. In an embodiment, a separate step or additional step can involve taping a raised edge at the tail (or other portion) of a surfboard to apply and retain additional epoxy, or to add epoxy in the event that the epoxy ran off or drained from that area before fully curing.
At step 120, the leash plug 34 is installed. For example, epoxy is applied to the leash plug 34 and the leash plug 34 is installed in the hole drilled at step 116.
At step 122, the surfaces of the surfboard 10 are sanded fair and smoothed. In embodiments, the surfboard 10 can be progressively sanded with various grits and sanding blocks and/or an orbital sander. In embodiments, grits used can include two or more of 80, 15, 220, and 320. In embodiments, an orbital sanding sub-step and can be the final sub-step of step 122.
At step 124, the fin boxes 22 are opened and the fins 20 installed. For example, epoxy and the layer 40 covering slot openings in the fin boxes 22 is cut away and the fins 20 installed in the slots.
Other forming, machining, or assembly techniques (e.g., cutting, shaping, bending, fusing, applying, joining, adhering, curing, et cetera) can be utilized in alternative or complementary embodiments without departing from the scope or spirit of the innovation.
The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.
