U.S. patent application number 10/741279 was filed with the patent office on 2004-08-12 for fastener for fiberglass and other composite structures.
Invention is credited to Grosch, Gregory E..
Application Number | 20040156696 10/741279 |
Document ID | / |
Family ID | 34657406 |
Filed Date | 2004-08-12 |
United States Patent
Application |
20040156696 |
Kind Code |
A1 |
Grosch, Gregory E. |
August 12, 2004 |
Fastener for fiberglass and other composite structures
Abstract
A threaded fasteners combines two or more of (a) a self-drilling
tip that is long enough and/or sufficiently distanced from the
threads to assure that drilling action is complete before the first
thread engages the surface of the work piece, (b) high-low threads,
and (c) a factory pre-applied adhesive/sealant. Such fasteners are
especially advantageous in applications where connections to
fiberglass are needed, and especially in applications such as boats
or other transportation vehicles where leaks resulting from drilled
cavities are problematic.
Inventors: |
Grosch, Gregory E.; (Laguna
Beach, CA) |
Correspondence
Address: |
ROBERT D. FISH; RUTAN & TUCKER, LLP
P.O. BOX 1950
611 ANTON BLVD., 14TH FLOOR
COSTA MESA
CA
92628-1950
US
|
Family ID: |
34657406 |
Appl. No.: |
10/741279 |
Filed: |
December 19, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10741279 |
Dec 19, 2003 |
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10724560 |
Nov 26, 2003 |
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60429870 |
Nov 27, 2002 |
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60508143 |
Oct 1, 2003 |
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Current U.S.
Class: |
411/378 |
Current CPC
Class: |
F16B 11/006 20130101;
F16B 35/041 20130101; F16B 25/10 20130101; F16B 25/0068 20130101;
B29C 66/721 20130101; B29C 66/7212 20130101; B29C 65/562 20130101;
F16B 23/003 20130101; E01B 9/10 20130101; B29C 65/561 20130101;
F16B 25/0031 20130101; B29C 66/721 20130101; B29C 65/00 20130101;
B29C 66/7212 20130101; B29K 2309/08 20130101 |
Class at
Publication: |
411/378 |
International
Class: |
E01B 009/10 |
Claims
What is claimed is:
1. A method of using a composite material, comprising: providing a
self-drilling fastener having high-low threads, and wherein the
fastener has a drill tip point that is distanced at least 2 mm from
the threads; and screwing the fastener into the composite
material.
2. The method of claim 1, wherein the drill tip point is distanced
at least 5 mm from the threads.
3. The method of claim 1, wherein the drill tip point is distanced
at least 10 mm from the threads.
4. The method of claim 1, wherein the drill tip point is distanced
at least 15 mm from the threads.
5. The method of claim 1, wherein the drill tip point is distanced
at least 5 mm from the threads and the drill tip point is
milled.
6. The method of claim 1, wherein the fastener comprises a 300
series steel.
7. The method of claim 6, wherein the fastener is selected from the
group consisting of a 304 stainless steel and a 316 stainless
steel.
8. The method of claim 1, wherein the fastener comprises a 18/8
stainless steel.
9. The method of claim 1, wherein the composite comprises a
fiberglass reinforced plastic.
10. The method of claim 9, wherein the fiberglass reinforced
plastic has a gelcoat and the fastener is screwed into the
fiberglass reinforced plastic through the gelcoat.
11. The method of claim 1, wherein the composite comprises a
fiberglass reinforced plastic panel.
12. The method of claim 1, wherein the composite comprises a
section of a transportation vehicle.
13. The method of claim 1, wherein the composite comprises a
section of a boat.
14. The method of claim 1, further comprising using the fastener to
attach an object to the composite.
15. The method of claim 1, further comprising using the fastener to
attach an object to the composite through a gelcoat.
16. The method of claim 1, further comprising using the fastener to
attach together two pieces of the composite.
17. The method of claim 1, further comprising applying an
adhesive/sealant to the fastener.
18. The method of claim 1, wherein the fastener has a pre-applied,
self-curing adhesive/sealant.
19. The method of claim 1, wherein the drill tip point is distanced
at least 5 mm from the threads, and the fastener comprises a
material selected from the group consisting of a 300 series
stainless steel and a 18/8 stainless steel, the composite comprises
a fiberglass reinforced plastic with a gelcoat, and the fastener is
screwed into the fiberglass reinforced plastic through the
gelcoat.
20. The method of claim 19 wherein the fiberglass reinforced
plastic is part of a boat.
Description
[0001] This application is a continuation-in-part of U.S. utility
application Ser. No. 10/724,560, titled "Fastener for Fiberglass
and Other Composite Structures" and filed Nov. 26, 2003, which
claims the benefit of U.S. provisional application No. 60/429,870
tiled "Fastener for Fiberglass" filed on Nov. 27, 2002, and U.S.
provisional application No. 60/508,143 titled "Fastener for
Fiberglass and Other Composite Structures" filed on Oct. 1, 2003,
each of which is incorporated herein by reference in its
entirety.
FIELD OF THE INVENTION
[0002] The field of the invention is fasteners and fastening
methods.
BACKGROUND OF THE INVENTION
[0003] Threaded fasteners can readily damage the fiberglass
reinforced plastic (FRP) or other composite material used in
applications such as boat building. Among other things, many of the
known fasteners can shatter and crack the un-reinforced outer
gelcoat surface of the FRP, causing it to spall. Additional
problems can occur when the rotating threads of a fastener, which
is typically an externally threaded sheet metal screw, bore into
the FRP, jamming the threads of the fastener into the bored cavity.
The amount of force required to pull the jammed fastener out of the
destructively fashioned FRP cavity is minimal, increasing the
incidence of fastener "pull-out" and "strip-out", which occurs when
the fastener spins freely in the connection.
[0004] It is known that these problems can be reduced by
pre-drilling or pre-forming a cavity into FRP. In such instances it
is recommended that the installer use a fastener with tapping
threads having a major diameter, the measurement of the greatest
outside diameter of the threads (the crest), which is slightly
greater than the diameter of the cavity. In the boat building
industry such fasteners commonly have type "A" or "AB" threads, but
in other industries the fasteners are known to have type "25", "B",
"Trilobular" "Thread-rolling" or "High-low" (Hi-Lo) threads.
High-low threaded fasteners alternate one high and one low thread
along the shank of the fastener.
[0005] Pre-drilling or pre-forming a cavity are not, however,
completely satisfactory solutions. In addition to the added
manufacturing costs involved, pre-forming limits the amount of load
that can be placed on the fastener before pull-out or spin-out.
Additionally, the diameter of the threads can be only slightly
larger than the diameter of the cavity to avoid shattering or
cracking the FRP.
[0006] The holding problem can be addressed by dispensing an
adhesive/sealant (such as 3M.TM. 5200 adhesive/sealant) into the
cavity. The adhesive aspect of the dispensed material bonds the
fastener into the cavity, thereby reducing the chance of fastener
spin-out and/or pull-out. The sealant aspect of the dispensed
material helps to prevent moisture and water from migrating into
the cavity. For brevity herein, the term adhesive/sealant is used
to denote any material that comprises an adhesive and/or a
sealant.
[0007] Although advantageous in many ways, these prior art methods
of using adhesive/sealants are also problematic. Among other
things, strength of the attachment relies largely on the adhesive
rather than the mechanical bond of the threads into the wall of the
cavity. In addition there is no adequate method of determining if a
seal has been formed around the entire circumference of the body of
the fastener. This is especially important in the boat building
industry, which often incorporates foam and balsa cores in its
hulls and superstructures. Moisture or water migrating into the
area between the outer laminate and the core material can
compromise the bond between the two materials, and can cause them
to delaminate. In addition, if water is allowed to saturate the
core material of the assembly, it can seriously comprise the entire
structure, sometimes rendering it unsalvageable. Applying an
adhesive/sealant into a pre-formed cavity is also labor intensive,
requiring multiple steps that can increase manufacturing costs.
[0008] It is known to factory pre-apply a adhesive/sealant coating
or "patch" onto the threads of some types of machine screws before
they are sold to end-users. Factory pre-applied adhesives/sealants
are "dry to the touch", and ideally remain dormant until the
shearing action of engaging the fastener into a nut or preformed
cavity causes them to cure. There are numerous advantages to this
approach, including improved resistance to pull-out, spin-out and
vibration. Surprisingly, while this method is widely known in the
automotive, aerospace and furniture industries, it has apparently
never been applied to fasteners used in the assembly of FRP
structures. The closest that the prior art comes to pre-coated
screws that provide a water-tight, moisture and vapor-proof seal is
U.S. Pat. No. 5,260,100 to Day (November 1993). But there, the
threads are coated with a liquid or pasty sealant, which is then
over coated with a dry, hard material.
[0009] Thus, there is still a need for new types of fasteners in
boat building and other industries that use fiberglass and other
composites. There is also a need to adapt some of the methods known
in other fields to the boat building and other industries that use
composites.
SUMMARY OF THE INVENTION
[0010] The present invention is directed to threaded fasteners that
combine two or more of (a) a self-drilling portion that is long
enough and/or sufficiently distanced from the threads to assure
that drilling action is effectively complete before the first
thread engages the surface of the FRP work piece, (b) external
high-low threads, and (c) a factory pre-applied adhesive/sealant.
Thus, the various fastener features disclosed herein may be
combined in any suitable manner. For example, some of the novel
fasteners contemplated herein may comprise high-low threads coated
with adhesive/sealant, whereas others may comprise high-low threads
and a self-drilling tip or point (with the terms "tip" or "point"
being used interchangeably herein), with or without an
adhesive/sealant.
[0011] The self-drilling tip or point is preferably chosen to be
appropriate for the material of the work piece. For example, a
fastener inserted into a gelcoated fiberglass panel would
preferably have a forged or milled drill tip that minimizes
cracking and spalling of the gelcoat. Milled self-drilling points
are generally more expensive to produce, but are considered to be
advantageous in that regard. Regardless of the type of drill-tip
chosen, the distance between the tip of the fastener and the thread
is preferably about 1/8.sup.th-5/8.sup.th inches, (or about 3-15
mm) when working with FRPs'. In other embodiments that distance can
be as small as 0.25 mm, or greater than 15 mm. All ranges set forth
herein include the endpoints.
[0012] Even though it has apparently not been previously
appreciated, course high-low threads are well adapted for
engagement into FRPs'. The high, threads provide deep thread
engagement and high shear values, while the inclusion of low
threads reduces the tendency of the FRP to crack as the fastener is
being driven. All suitable hi-lo threads are contemplated,
including those where there is only minimal differences between the
crests of the high and low threads, to those where there is a very
significant difference between the crests of the high and low
threads.
[0013] Pre-coated adhesives and/or sealants preferably lie dormant
on the fastener until the shearing action of the threads engaging
the FRP releases, mixes, activates the substance(s), or in some
other manner triggers the curing process. After curing, the
adhesive/sealant reduces the incidence of fastener pull-out and
spin-out, and provides a seal around the body of the fastener. In
some instances fasteners comprising a factory pre-applied
adhesive/sealant can even be reused, since some of the
adhesive/sealant may remain unactivated when the fastener is first
used.
[0014] It should be noted that although the use of a pre-applied
adhesive/sealant is described primarily in relation to threaded
fasteners in the form of screws, it is applicable to other
fasteners as well, with nail type fasteners being but one example.
The concept is also applicable to different types of threaded
fasteners, and, more particularly, to different types of screws. As
such, the style, shape and dimensions of the fastener will likely
vary between embodiments. For example, when attaching a thick
bracket to a fiberglass wall, a screw may be used that has a
non-threaded portion near the head that is approximately the length
of the hole in the bracket through which the screw is inserted. As
another example, inventive fasteners may have a flat, pan, oval,
truss or other head design, and can have a hex, Phillips, slotted,
square, Torx.TM. or other drive design.
[0015] Contemplated fasteners can be used advantageously in many
different applications. Of particular interest are boat building
and other construction where connections to FRPs' are needed, and
where leaks around fasteners, resulting from bored or drilled
cavities, are problematic.
[0016] Various objects, features, aspects and advantages of the
present invention will become more apparent from the following
detailed description of preferred embodiments of the invention,
along with the accompanying drawings in which like numerals
represent like components.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a perspective view of a screw.
[0018] FIG. 2 is a perspective view of an alternative screw.
[0019] FIG. 3A is an end view of another alternative screw.
[0020] FIG. 3B is an side view of the screw of FIG. 3A.
[0021] FIG. 3C is a enlarged view of a portion of the screw of FIG.
3B.
[0022] FIG. 3D is a side view of another alternative screw.
[0023] FIG. 4 is a cutaway view of a thread of a screw.
[0024] FIGS. 5A-5E are cutaway views of portions of alternative
screws.
[0025] FIGS. 6A-6B are cutaway views of the heads of screws.
[0026] FIG. 7 is an exploded view of an object being attached to a
section of FRP using three screws.
DETAILED DESCRIPTION
[0027] General Aspects Of Fasteners
[0028] In FIG. 1, a fastener in the form of a screw 100 has a head
110, a body 120, and a self-drilling tip 130. Head 110 includes
bearing surface 111. Body 120 includes cylindrical shank 121 and
high and low threads 123 and 122, with threads 111 comprising
surface 122A. Threads 122 and 123 are at least partially coated
with, and thereby "hold" a self-curing adhesive/sealant (not shown
in FIG. 1 that is dry to the touch under usual circumstances, but
discussed in relation to FIGS. 4-6B).
[0029] Similarly in FIG. 2, a fastener in the form of a screw 200
has a head 210, a body 220, and a self-drilling tip 230. Head 210
includes bearing surface 11. Body 220 includes cylindrical shank
221 and high and low threads 223 and 222, with threads 211
comprising surface 222A. Threads 222 and 223 hold a substantially
dry self-curing adhesive/sealant (not shown in FIG. 2, but
discussed in relation to FIGS. 4-6B). Screw 200 differs from screw
100 both in regard to the type of head (110, 210), and how much of
the shank (121, 221) is covered by threads (122, 123, 222,
223).
[0030] FIGS. 3A-3D illustrate various lengths and diameters of
screws 100 and 200 where L1 is the overall length of the screw, L2
is the length/thickness of the head (110, 210), L3 is the length of
the threaded portion of the body (120, 220), L4 is the length of
the self-drilling tip (130, 230), L5 is the depth of the recess,
and for screws which do not have threads extending the entire
length of the body between the head (110, 210) and self-drilling
tip (130, 230), L6 is the length of the non-threaded portion of
body (120, 220), D1 is the diameter of the shank (121, 221) and is
sometimes referred to as the minor diameter of the fastener, D2 is
the diameter (crest to crest) of the high threads (123, 223) and is
sometimes referred to as the major diameter of the fastener, D3 is
the diameter (crest to crest) of the low threads (122, 222), D4 is
the head outer diameter, and D5 is the diameter of the recess (not
shown in FIGS. 1 and 2). Dimensions of corresponding screws in the
prior art are already known.
[0031] Although the various dimensions will vary between
embodiments, it is contemplated that it may be advantageous for an
embodiment having threads extending the length of the body to have
L1 approximately 2.4 mm, L2 approximately 1.4 mm, L3 approximately
16.65 mm, L4 6.35 mm, L5 approximately 1.4 mm, D1 approximately
3.85 to 3.95 mm, D2 approximately 4.5 to 4.7 mm, D3 approximately
3.8 to 4.0 mm, D4 approximately 7.43 to 8.43 mm, and D5
approximately 3.94 mm.
[0032] The tip, shank, threads, and head are preferably made of a
material that is corrosion resistant. The presently preferred
material is a series 300 stainless steel, sometimes written as
18-8, and especially 316 or 316L stainless steel. It should be
appreciated that alternatives may utilize any other suitable
materials or combinations of materials, including but not limited
to other forms of stainless steel, zinc plated steel, brass,
bronze, and plastic.
[0033] Although contemplated fasteners can have any type of head,
as partially illustrated by the pan head 110 of fastener 100 and
the flat head 210 of fastener 200, preferred head styles are flat,
oval, pan and truss. The preferred drive style is hex. The choice
of head will depend mostly on the application for which the
fastener is intended. As such, other embodiments may include, but
are not necessarily limited, to flat heads, oval heads, pan heads,
round heads, fillister heads, binding heads, (holt?) heads, truss
heads, hexagon heads, and acorn heads with Phillips, slotted,
square, Torx.TM. or other drive design. It is also contemplated
that in applications where a seal is to be formed about the
fastener to preserve the integrity of any barrier pierced by the
fastener (such as a fiberglass boat hull), the use of a head having
a bearing surface that conforms to the shape of the juxtaposed
surface will assist in the formation of such a seal.
[0034] For certain flat head and other fasteners adapted to be
countersunk into the outer surface of FRPs', it is desirable to
provide serrations (nibs) that extend radially on the underside,
bearing surface of the head. Nips provide for a self-countersinking
head that reduces friction when the underside of the head first
engages the surface of the FRP minimizing surface spalling. Nibs
also aid in locking the fastener in the material providing
protection from vibration. At least four such nibs are preferable,
and six nibs are considered to be optimal. Other embodiments may
include 4-8 nibs or some other quantity of nibs.
[0035] As known in the prior art, fastener heads may be shaped, or
may include recesses, protrusions, or combinations thereof to
facilitate mating the fastener with a screwdriver or other driving
tool. Drives may include Phillips, slotted, square, Torx.TM. or
other design.
[0036] Driving tools include Philips and flat blade screwdrivers,
Torx drivers.RTM., and Allen wrenches.
[0037] Threads
[0038] The specifications of the pitch for the preferred high-low
course threads are 6-15, 8-15, 10-12, 1/4-10. The first number is
the body diameter and the second shows the combined number of high
and low threads per inch. The preferred threads have a 70.about.73
degree included angle thread profile, which is steeper than the
standard pitch specifications (6-20, 8-18, 10-16, 12-14) for course
self-drilling screw threads The steeper profile provides faster
insertion into the FRP, reducing friction which causes cracking.
Fasteners for masonry, which are not self-drilling, have sharp
points and thread specifications with an included angle of 76
degrees which is comparable to the threads on the inventive
fasteners. However, the crest of the "hi" thread on a masonry
fastener, as compared to the differential in the major diameter of
the "hi" thread and the diameter of the self-drilling tip on the
inventive fasteners, combined with the lower included angle would
cause unacceptable cracking and spalling of the gelcoat or outer
surface of a FRP structure. As used herein "included angle" is the
angle between the flanks, measured in an axial plane section where
the flanks of a thread are the straight sides that connect the
crest and the root, the crest of a thread is the prominent part of
a thread, and the root is the bottom of the groove between the two
flanking surfaces of the thread. As used herein the "pitch" of a
thread is the distance, measured parallel to its axis, between
corresponding points on adjacent surfaces, in the same axial plane.
However, pitch may be approximated herein by specifying the number
of threads per inch (TPI).
[0039] Contemplated fasteners include those where all of the
threads are of the high-low design, as well as those having a
section of high-low threads and another section of a different type
of threads. The threads may extend along the entire length of the
body of the fastener, as shown by threads 122, 123 of body 120 of
fastener 100, or may extend only along a portion of the length as
shown by threads 222, 223 of body 220 of fastener 200. Having the
threads extend only part way along the body of a fastener helps
prevent pull-through during the drilling stage, and jacking, where
a top piece of material pulls away from a base material because the
fastener threads in the top material force the top material up the
body of the fastener.
[0040] Drilling Tip
[0041] Drilling tip 130 is preferably a self-drilling, fluted
point, adapted to effectively drill completely through the FRP or
other composite before the threads (122, 123, 222, 223) engage the
outer surface. This arrangement is intended to prevent
pull-through, which causes cracking and spalling and prevents a
strong mechanical connection between the fastener and the FRP. To
that end it is advantageous to have the drill tip distanced from
the threads by between 1/8" and 5/8", and more preferably between
1/4" and 3/8". In metric terms the preferred tip to thread distance
is preferably between about 3 mm and 1.5 mm, although it is
contemplated that the distance can be as low as 0.25 mm, or greater
than 1.5 mm. Depending on the application, preferred tip to thread
distances are at least 3 mm, 5 mm, 10 mm, or 15 mm. Drilling tip
130 can comprises a forged or pinch point or any other suitable
configuration, but most preferably is milled for precise drilling
to reduce the likelihood of cracking and spalling the outer surface
of the FRP.
[0042] The length of the drill flute advantageously corresponds to
the thickness of the FRP that can be drilled. The flute provides a
channel for chip removal during drilling, and will increase the
friction and slow down the cutting action if it becomes impeded in
the material. For these reasons the length of the flute on the
point of the inventive fastener should approximate the practical
overall length of the tip.
[0043] Adhesive/Sealant
[0044] Where the threads are at least partially factory pre-coated,
the coating is preferably made from just above the drill tip along
a distance corresponding to the thickness of the FRP structure.
Such coatings can be made in a vertical or angled strip, in a
patch, or full coated around the circumference of the area. As
discussed elsewhere herein, the coating preferably contains an
adhesive/sealant that is dry to the touch. In any event, the
coating advantageously remains dormant until the shearing action of
engaging the fastener into a nut or cavity triggers a curing
process. Curing can then occur in any suitable manner, but
generally occurs as a result of a chemical reaction between two
different components in the adhesive. The presently preferred
material is Scotch-Grip.TM. Fastener Adhesive 2353, marketed by the
3M Company. The adhesive/sealant can have any color, but is
preferably white for use in boats and other FRP structures.
[0045] The adhesive/sealant can be advantageously encapsulated in
microcapsules. As used herein, the term "microencapsulate" means to
enclose in microcapsules, where a "microcapsule" is a small,
sometimes microscopic capsule designed to release its contents when
broken by pressure, dissolved, or melted. FIG. 4 illustrates the
surface of a fastener comprising a shank 421, a thread 422, a
thread surface 422A and a plurality of microcapsules 470. FIG. 4
and FIGS. 5A and 5B depict microcapsules deposited on the threads
as distinct units. FIGS. 5C-5E depict microcapsules that are
included as part of a layer of material that fully or partially
covers surface 422A.
[0046] Microcapsules (in individual or layered form) may consist
essentially of only an adhesive/sealant as illustrated by FIGS.
5B-5D, or may comprise an adhesive or sealant encapsulated by
another material. This is illustrated in FIGS. 5A and 5E. In FIG.
5A, adhesive/sealant 572 is encapsulated by material 571 in
microcapsules 570 on the surface 522A of a thread 522. In FIG. 5B,
adhesive/sealant 573 forms 570 on surface 522A of a thread 522. In
FIG. 5C, layer 573 comprises adhesive/sealant microcapsules on
surface 522A of thread 522. In FIG. 5D, the layer 573 of FIG. 5C is
non-continuous as it contains or more exposed regions 580. In FIG.
5E adhesive/sealant 572 is partially encapsulated by material 571
but is non-continuous so leaves exposed areas 580 of surface
522A.
[0047] Although it is preferred that the threads be coated with
adhesive/sealant as illustrated by FIG. 4, it is contemplated that
other portions of the fastener may be coated in addition to or in
place of the coating on the thread surfaces. As such the shank may
be coated and/or the bearing surface of the head may be coated as
illustrated by FIGS. 6A and 6B. In FIGS. 6A and 6B, bearing surface
611 of head 610 attached to shank 620 is coated with microcapsules
that are either distinct units 670 as shown in 6A, or in a layer
673 as shown in FIG. 6B.
[0048] Methods and Applications
[0049] FIG. 7 generally depicts a handle 810 being attached to a
section of composite 820 using two screws 830. The handle 810 is
employed euphemistically in the figure to represent any object that
can be attached to the composite section using fasteners. Other
contemplated objects, for example, include brackets, hinges, wall
hangings, furniture, rails, and electronics such as telephones and
radios. Handle 810 thus also represents a second piece of composite
that is being screwed into the composite section 820.
[0050] The composite section 820 is likewise intended to be
generically representative of any composite material, including a
fiberglass wall, beam, or other structure. Thus, although the
portion of the composite section 820 in FIG. 7 is shown as having
three layers, a gelcoat 822, a hard plastic section 824 and a soft
core 826, alternative contemplated composite sections may have
different types and/or number of layers. The composite section 820
shown should therefore be interpreted as any composite portion of a
boat, plane, car or other transportation vehicle, or in any other
application.
[0051] The screws 830 should once again be viewed euphemistically,
to include any of the fasteners contemplated herein that have
drill-tip points. Thus, although both of the screws 830 have a flat
head design, with high-low threads to which a self-curing
adhesive/sealant may have been applied, the screws 830 shown are
representative of other fasteners described herein, with different
head or thread features, with or without a self-curing
adhesive/sealant. Of particular interest is the tip to thread
distance 832. That distance should be long enough to prevent
significant pull through as the screw is being inserted. In most
circumstances this means that the tip to thread distance 832 would
be at least as long as the thickness 825 of the FRP 824.
[0052] Although specific examples of novel fasteners and methods
using same have been disclosed, those skilled in the art will
appreciate that many more modifications besides those already
described are possible without departing from the inventive
concepts described herein. Moreover, in interpreting the
disclosure, all terms should be interpreted in the broadest
possible manner consistent with the context. In particular, the
terms "comprises" and "comprising" should be interpreted as
referring to elements, components, or steps in a non-exclusive
manner, indicating that the referenced elements, components, or
steps may be present, or utilized, or combined with other elements,
components, or steps that are not expressly referenced.
* * * * *