Note: Descriptions are shown in the official language in which they were submitted.
~276~5
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BUILDING PANEL
BACKG~OUND_OF T~E INVENTION
1. Field of the Invention
The present invention relates to building
panels formed of thin-walled, molded hardboard and
adapted to be used for interior and exterior roof and
wall surfaces on a wide variety of building structures.
In accordance with the present invention it
has been found that hard~oard formed of composite
wood fibrous material can ~e molded in both wet and
dry processes into relatively intricate shapes and
profiles to provide roofing and siding products that
closely resemble real wood and lumber yet requiring
much lower quantities of wood materials for manufac-
ture and consequently having a lower weight per foot
of surface area coverage than real wood counterparts.
Moreover, in accordance with the present
invention it has been found that relatively intricate
and complex shapes and profiles can be molded in thin
walled hard~oard material to provide increased strength
and resistance to wind uplift forces, drying out and
curl up at corners of the panels, even though the
panels weigh substantially less than real wood compo-
nents and considerably less than substantially thicKer,
pressed fiber panels heretofore used, which panels
often required much greater thic~nesses in order to
provide suitable stiffness and structural characteris-
tics.
2. DescriPtion of the_Prior Art
Various hard~oara panels, panel siding and
lap siding products of hardboard have been utilized
for surfacing the exterior walls and roofs of build-
ings. In addition, lap siding and roofing products
formed of aluminum ana vinyl have been utilized and
many of these products have attempted to replicate or
12769~
--2--
simulate the appearance of historical or
traditional siding and roofing materials made of wood.
A number of U. S. patents have been issued
on roofing, panel siding, panels and lap siding pro-
ducts and are listed below as follows:
Fink et al RE. 24,246 Ture~ 3,8~7,667
Montross 373,373 Gadsby 3,89Y,855
Ochs 2,264,546 Carothers 3,943,677
Brady 3,333,384 Allen et al 4,366,197
Kneisel 3,326,493 Eaton 4,015,392
Johnson 3,643,394 Geimer et al 4,061,813
Mattes 3,703,7~5 Kirkhuff 4,065,8~
Wilson et al 3,720,031 Golder et al 4,102,106
Hanlon et al 3,796,586 Tellman 4,188,762
Wilson et al 3,848,383 Tellman 4,261,152
Eaton et al 3,~4~,384 Tellman 4,266,382
Kirkhuff 3,852,934 Gleason et al 4,27~,106
Wheeler 3,868,300 Hanlon et al 4,366,197
OBJECTS OF THE INVENTION
It is an important object of the present
invention to provide a new and improved building panel
formed of thin-walled, molded hard~oard.
More particularly, it is an object of the
present invention to provide a building panel of the
character described having a deeply embossed or molded
outer surface resembling a plurality of shingles or
shakes aligned in a common course.
Still another object of the present inven-
tion is to provide a new and improvea roofing panel
having a deep drawn, molded outer shell formed of
relatively thin hardboard with a transverse cross
sectional profile extending between the upper and
lower edges of the panel having an overall depth
measured between a back plane extending between a
lZ76~'S
--3--
lower and upper edge portion of the panel and an outer
surface that is considerably greater than the thick-
ness of the shell material at any location thereon
measured directly between the outer and inner faces
thereof.
Yet another object of the present invention
is to provide a new and improved building panel of
the character described which is extremely light in
weight, especially for the amount of surface area
covered, and which closely resembles real wood cedar
shingles or shakes as they are customarily applied to
roofing or wall surfaces of a building.
Still another object of the present inven-
tion is to provide a new and improved ~uilding panel
of the character descri~ed which is extremely economi-
cal to produce and which requires minimal labor to
install because of greater facility in handling during
installation and application, and 3ecause of the rela-
tively large surface area covered by each panel.
Still another object of the present inven-
tion is to provide a new and improved building panel
of the character described employing a plurality of
shingle or shake-like elements having downturned edge
portions along opposite sides and a downturned lower
edge for providing extremely good resistance against
wind uplift forces and curling forces generated at
the corners normally caused by heating, cooling and
repeated wetting and drying from prolonged exposure
to weather.
Still another object of the present inven-
tion is to provide a new and improved thin-walled,
molded hardboard building panei of the character
described having a row of fastener receiving deptes-
sions formed therein adapted to facilitate the instal-
1276~5
--4--
lation of the panels with fasteners which may be ap-
plied with automatic fastener guns and the like.
Yet another object of the present invention
is to provide a new and improved building panel of
the character described which is competitive from
both an initial cost and a labor-saving standpoint in
comparison to to conventional asphalt shingles and
siding panels as well as other forms of hardboard,
wood, vinyl and aluminum, siding and roofing products.
Yet another object of the present invention
is to provide a new and improved building panel of
th~ character described having extremely good struc-
tural characteristics for resisting uplift by wind
forces and/or resisting cupping or curl at the corners
and lower edge portions that are exposed to the weather.
Yet another object of the present invention
is to provide a new and improved moldea building panel
of the character described having a relatively thin-
wall, yet a relatively deep drawn, intricately shaped,
molded outer surface which closely resembles a plural-
ity of real wood shakes or shingles laid up in a com-
mon course or row.
Yet another object of the present invention
is to provide a new and improved thin-walled, molded
hardboard building panel of the character descri~ed
which is designed to handle expansion and contraction
resulting from moisture absorption and moisture loss
without significant buckling, corner curl-up or other
problems resulting from dimensional changes caused by
prolonged exposure to weather.
Still another object of the present inven-
tion is to provide a new and improved building panel
of the character descri~ed having a relatively intri-
cate and complex profile and which can easily and
rapidly be installed on a building wall or roof sur-
~'76~ZS
--5--
face, even by an unskilled artisan, yet resulting in
a wall surface having an outstanding appearance and
excellent structural and ov~rall pe~formance charac-
teristics.
Yet anot~er object of the present invention
is to provide a new and improved thin-wall, molded
hardboard panel of the character described having
minimum lap loss when laid up in overlapping courses
on a building surface.
~
The foregoing and other objects and advan-
tages of the present invention are accomplished in a
new and improved building panel for exterior and in-
terior wall and roof surfaces comprising a shell form-
ed of relatively thin, deep drawn, molded hardboard
having upper and lower edges, opposite ends, and an
intricately shaped, molded outer face adapted for
exposure to the weather with a contoured back surface
generally following the contour of the deep drawn
outer face.
The shell has a cross-sectional profile
taken transversely between the upper and lower edges
of the panel comprising a lower edge portion which
extends upwardly and outwardly of the lower panel
edge from a back plane touching points on the back
surface of the panel. The lower edge portion joins
an intermediate panel facia portion spaced outwardly
of the back plane and a row of fastener receiving
depressions is formed along an upper edge of the in
termediate facia portion, each depression including a
recessed base spaced inwardly from an outer surface
thereof and having a back face generally lying on the
back plane of the panel.
The panel also includes an upper edge por-
tion upwardly of the row of fastener receiving depres-
12~64~5
--6--
sions which terminates along the upper edge of the
panel and is adapted to lie beneath the lower edge
portion and a segment of the intermediate facia por-
tion of one or more panels laid up in a next higher
overlapping row or course. The panels are defined
with an overall thickness dimension between an outer
face of the panel and the back plane that is substan-
tially greater than the nominal wall thickness of the
panel shell between the inner and outer surfaces there-
of at any location thereon. Thus, the panel providesthe appearance of thick butt shakes or shingles but
is considerably lighter and utilizes much less materi-
al than real wood counterparts or relatively thick
hardboard panels that are only embossed on the outer
face.
G~
For a better understanding of the present
invention reference should be had to the following
detailed description taken in conjunction with the
drawings, in which:
FIG. 1 is a fragmentary elevational view of
a typical building structure utilizing building panels
constructed in accordance with the present invention
and laid up in parallel courses or rows in overlapping
relation on a roof surface thereon;
FIG. 2 is a vertical cross-sectional view
taken substantially along lines 2-2 of FIG. 1;
FIG. 3 is a perspective view of an embodi-
ment of a new and improved building panel constructed
of thin-walled, molded hardboard in accordance with
the features of the present invention and showing an
outer face and a lower butt edge thereof;
FIG. 4 is a longitudinally extending cross-
sectional view of the panel of FIG. 3 taken substan
- 35 tially along lines 4-4 of FIG. 3;
~2~764Z~
FIG. 5 is a cross-sectional view taken su~-
stantially along lines 5-5 of FIG. 4;
FIG. 6 is a perspective view of the panel
of FIG. 3 looking downwardly in a direction along the
upper edge and outer surface of the panel;
FIG. 7 is a fragmentary upper edge eleva-
tional view of the panel looking in the direction of
arrow 77 of FIG. 6;
FIG. 8 is a fragmentary perspective view of
a building roof structure with several panels applied
thereon and another panel shown in elevated position
ready for application;
FIG. 9 is a fragmentary cross-sectional
view taken substantially along lines 9-9 of FIG. 8;
FIG. 10 is a fragmentary perspective view
of a pair of panels in accordance with the present
invention shown in juxtaposition prior to installation
of the panels in a single course or row along a roof
surface of a building;
FIG. 11 is a transverse fragmentary cross-
sectional view taken substantially along lines 11-11
of FIG. 10;
FIG. 12 is a similar transverse cross-sec-
tional view taken substantially along lines 12-12 of
FIG. 10;
FIG. 13 is a transverse cross-sectional
view taken substantially along lines 11-11 and 12-12
of the panels of FIG. 10 but after the panels have
been installed in overlapping relationship;
FIGS. 14 and 15 illustrate a pair of panels
in accordance with the present invention in angularly
disposed relation to one another prior to stacking
together in a bundle;
~276~
--8--
FIG. 16 is a perspective view of a pair of
accessory panels in accordance with the present inven-
tion utilized along a gable end of a roof structu~e;
FIG. 17 is a fragmentary perspective view
of a roof structure with gable end accessory panels
as shown in FIG. 16 installed in place along the ga~le
end; and
FIG. 1~ is a fragmentary cross-sectional
view of a hip portion of a roof structure illustrating
a roll of accessory panels of the type shown in FIG.
16 as utilized for application along the hip of the
roof structure.
DESCRIPTION OF A PREFERRED EMBODIMENT
Referring now more particularly to the draw-
ings, in FIGS. 1 and 2 is illustrated a building 30
of a general or conventional type employing a sloped
roof structure 32 and a vertical side wall 34. The
roof and wall are covered with an outer or weather
surface formed by a plurality of new and improved
building panels 40 which are laid up in end-to-end
relation in hori~ontal courses or rows. ~he panels
in each succeeding higher course overlap an upper
portion of the adjacent lower course or row as best
shown in FIG. 2.
Each building panel 40 is formed of deep
drawn, molded, thin walled, wood composite material
such as hardboard of a substantially uniform thick-
ness ~t" and is of a generally rectangular shape as
shown in FIGS. 3, 8, 14 and 15. The panels include a
contoured back surface 42 generally following the
variations in the outer face and bounded by an elon-
gated upper edge or head 44 and a generally parallel,
lower or butt edge 46 exposed to the weather. Each
panel is formed with a deeply drawn, molded outer or
weather face 60 designed to closely resemble a plural-
12~7~5
g
ity of real wood, thiCK butt cedar shakes or shingles.
The outer surface 60 includes elongated narrow strip
or head lap portion 62 along the upper edge and the
area of this strip comprises only a fractional or
minor portion of the total or overall surface area of
the whole building panel. The narrow head lap surface
along the upper edge is adapted to underlie a narrow
strip of back face along a lower portion of each suc-
ceeding panel or panels as the panels are laid up in
place in a next adjacent upper row or course (as shown
in FIGS. 8-9) . When laid up in place as shown, the
narrow overlapping or confronting portions of the
panels form a su~stantially tight head lap between
"S" (FIG. 9) successive courses or rows of panels on
a wall or roof.
The outer weather face 60 of each panel
includes a relatively large, lower surface or facia
portion 64 lying ~elow the narrow upper head lap 62
and delineated therefrom by a row of spaced apart
fastener receiving depressions 66 parallel of and
spaced intermediate the upper edge 44 and the lower,
exposed butt edge 46 of the panel. The generally
cup-shaped depressions 66 provide guidance for instal-
ling a single row of fasteners such as nails 45 for
holding the panels in place on a ~uilding wall or
roof surface. The panels 40 are provided with course
alignment end marks or ribs 6~, at each end, and these
course alignment marks serve to align the ends and
edges of panels in adjacent courses or rows as a roof-
ing or siding job proceeds.
In accordance with the present invention,the weather exposed, outer facia portion 64 of the
outer surface 60 is formed by a deep draw, molding
process to resemble closely in appearance, a plurality
of individual shakes or shingle~ e elements 64a.
lZ~76~
--10--
Each element is outwardly convex or inwardly concave
to provide a shallow, inverted, generally cup-shaped
configuration which is stiff and strong even though
the wall thickness is relatively small. Referring
now specifically to FIGS. 4, 5 and 9, each individual
shingle or shake-li~e element 64a is formed with a
shallow, inverted cup-shaped configuration in the
deep draw, molding process as each element includes a
thick butt, lower edge portion 65 comprising a seg-
ment of the overall longitudinal lower edge 46 of the
panel~ The lower edge portions slope up~ardly andoutwardly from a lower edge or apex 46a which touches
on a bac~ plane "A-A" defined to extend between the
lower edge 46a and the underside or apex 44a of the
upper panel edge 44 as shown in FIG. 5. The upwardly
and outwardly sloping lower edge portions 65 of each
individual shingle-like or sha~e element blend and
join with the outer facia portions 64a and a plurality
of these facia portions make up the overall weather
surface 64 of the panel. Each shingle or shake-li~e
element 64a also includes at least one upwardly and
outwardly or downwardly sloping side edge portion(s)
67, which portion(s) in cooperation with the lower
edge portion 65 provides stiffening and strength to
resist wind uplift forces and to resist any corner
curl up tendencies caused by the repeated absorption
and elimination of moisture in the hardboard material
over periods of prolonged exposure to the weather.
In accordance with a feature of the present
invention, the panels 40 are dimensioned with an over-
all thickness "T" (FIGS. 4, 5, and 7) measured between
the back plane "A-A" and an outer or front plane "B-
B" which i5 coextensive with outermost surface por-
tions of at least one shingle-li~e element(s) 64a and
a planar, fastener receiving strip 70, which strip
~L2~764~,~
runs longitudinally of the panel intermediate the
upper and lower edges and surrounds the longitudinal-
ly~spaced, fastener receiving, cup-shaped depre-
ssions 66. This overall thickness dimension "T"
S is substantially greater than the relatively ~hin
wall thicknes~ "t" measured directly between the
outer face 60 and the bac~ face 42 of the panel at
any point or location on the surface thereof. This
substantial difference between the overall panel
thickness "T" and the shell or wall thicknes~ "t~ of
the hardboard material is made possi~le by the deep
draw, molding process used to form the intricately
shaped outer surface 60 of the panel with the
shallow, inverted cup-shaped design of the individual
shingle-li~e elements 64a. These elements make up
the main facia area of the panel extending between
the intermediate, planar fastener strip 70 and the
lower panel edge 44 comprising about 80~-90% of the
overall or total surface area of the panel.
Each shingle-like element 64a integrally
joins a lower edge portion of the planar face of the
fastener strip 70 (containing the fastener receiving
depressions 66) with an upwardly and outwardly slop-
ing upper edge segment 69, thus resulting in an ex-
tremely strong panel construction even though the
actual amount of material present is relatively low
due to the fact that the wall thickness "t" is con-
siderably less than the general or overall thic~ness
"T~ of the panel as whole measured between the back
plane "A-A" and front plane "B-B".
For example, in a commercial embodiment of
the present invention the overall panel dimensions
may be approximately 12 inches high by 48 inche~ wide
in order to span three, 16 inch on center studs~
rafters or other supports. The thin wall ~t~ of the
~2764~
-12-
hardboard material making up the panel shell is
approximately 1/8" in thickness and the overall
thic~ness of the panels as a whole as measured by the
dimension "T" between the back plane "A-A" and
front or outer plane "B-B" may be as high as 3/4" to
1". This arrangement provides exceptional stiffness
and resistance against wind uplift forces even though the
amount of material required to make a panel is sub-
stantially less than that of a nominal 7/16" or 1~2"
thick hardboard panels of the type typically used for
siding and roofing panels.
The outer face plane "8-B" is coextensive
with portions of the planar outer surface of the
elongate~ fastener strip 70 in which the nailing or
fastener receiving depression 66 are formed, and these
depressions are generally shallow and cup-shaped,
having a circular or oval outline. Each depression
includes a flat, generally circular, base having an
underside that is coextensive with the back plane "A-
A" of the building panel. The upper surface of thebase is formed with a cross or other marker indentation
66a to guide a workman in positioning a nail or other
fastener which may be driven from an automatic tool
or fastener gun used for securing the panels in place
on a building wall or roof structure. The cup-shaped
depressions 66 are large enough to accommodate the
entire nose or drive track of an automatic fastener
driving tool and the depressions serve to generally
guide the positioning or placement of the drive track
of the tool on the panel so that the panels 40 can be
installed in a rapid fashion with the correct number
and placement of fasteners on the panel.
The narrow head lap or upper edge portion
62 of the panel is generally at a level lower than
the fastener strip face 70 and has an underside, gener-
~Z76~
-13-
ally coextensive with the bac~ plane "A-A" as best
illustrated in FIG. 5. In order to permit the drainage
of any moisture condensing or collecting above an
upper edge 44 of the panel in the space beneath the
facia or raised portion of the panels in a next hiyher
course, the upper edge por~ion 62 of the panel is
formed with a plurality of slightly elevated or rais-
ed, air and water drain passages 62a (FIGS. 3, 6, 7
and 10) and these passages permit air circulation
between upper and lower portions of the panels behind
the back surface.
In accordance with the presen~ invention,
the upper surface of the fastener strip 73 along a
portion between the lower edge of the row of the fas-
tening receiving depressions 66 and above the upperedges 69 of the individual shake-like elements 64a is
adapted to provide a flat ~earing surface "S" for
contact with the lo~er edges 46 of panels 40 which
are laid up in overlapping relation in a next higher
course or row as best shown in FIGS. 8 and 9. This
relatively tight overlapping arrangement between the
lower edges 46a of the upper panels and the planar
upper face of the strip 70 on lower panels generally
retards or stops the flow of wind driven water from
passing upwardly along the overlap area between suc-
cessive panel courses.
From the foregoing it will be seen that the
deep drawn, molded panels 40 in accordance with the
present invention have only a relatively small thic~-
ness "t" of hard~oard material yet provide a profileas shown in FIG. 5 that is strong and stiff. ~3ecause
of this strength, only a single row of nails or fas-
teners placed at spaced intervals in the depressions
66 along the strip 7~ is used to hold the panels in
place. Moreover, the fasteners are eventually cover-
~2~764~S
-14-
ed by overlapping panels in the next course. In the
overlapping arrangement of successive panel courses,
the lower edges 65 of the individual shake-like ele-
ments 64a rest on the lower portion of the planar
fastener strip 70 in the next lower course of panels,
and the panels are relatively free to expand and con-
tract without buckling or cracking. A single row of
nails or fasteners are used in each panel at appro-
priate intervals specified by the location of the
fastener receiving depressions 66 and the upper and
lower edges of the panels are not restrained by nail-
ing or other fasteners. The deep drawn, molded de-
sign of the panels and the resulting overall panel
thickness "T" substantially greater than the nominal
lS wall thickness "t" of material provides an aesthetic
appearance that closely replicates or resembles more
expensive and heavier, thick butt cedar shake or
shingles, bUt at a fraction of the cost, less lap
loss and at a smaller fraction of time required to
install a surface covering on a given surface area of
a roof or wall structure.
In comparison to real wood shakes or
shingles, the panels 40 are much easier to put in
place, align and install because a single panel
covers a surface area that requires a considerably
larger number (5 or 6~ of individual, real wood
shingles or shakes. The panels 40 have a minimum of
overlap in comparison to real wood shakes or shingles
and overall, cover a given surface area on a building
with a fraction of the weight, at a much lower cost,
and a minimum of application time being required for
installation the in comparison to real wood shakes.
The thin molded hardboard roofing and siding panels
40 of the present invention thus provide the best of
both worlds.
~Z764~5
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In accordance with the present invention,
the panels 40 are laid end to end in each course or
row with left hand end portions 72 of the panels
adapted to overlie, right hand end portions 74 of
adjacent panels to form a ship-lap, end to end joint.
As best shown in FIGS. 10-13, the overlying left hand
end portion 72 of a panel is adapted to cover over a
narrow portion of an underlying right hand end por-
tion 74 of an adjacent panel. The right hand end
portions of the panels are formed with an upwardly
projecting stiffening ri~ 74a adapted to provide a
positive interlock for ensuring that the overlying
end portions 72 and 74 do not become inadvertently
disengaged. As illustrated in FIG. 3, the spacing
between the rib 74a and the adjacent edge portion of
the shake or shingle like element 64a is sufficient
to permit the downwardly sloping left hand edge 67 of
the overlapping panel segment 72 to float or move
without ~ecoming disengaged from the overlying, ship-
lap joint arrangement. This unique construction per-
mits the exposed lower portions of the panels encom-
passing the facia surface area 64 to expand and con-
tract without buckling or restraint in a longitudinal
direction or in a transverse direction. Because the
underlying right hand end segments 74 are relatively
thin, the upstanding rib 74a tends to provide an
added stiffness to the structure and prevents inadver-
tent breakage during storage, transportation, handling
and application. Such damage might result if a thin
flat edge portion was constructed without such a stif-
fening ri~ therein.
Referring now to FIGS. 1 and 16-18, pairs
of accessory panels 80 are provided for hips and ridges
of a roof structure and the end of a gable as shown
in FIG. 17. For this purpose, accessory panels 80
~.zt76~z'~
-~6-
are formed of thin-wall, molded hardboard material
like the basic panels 40. The accessory panels are
provided with a downturned edge portion 80a along one
edge to provide an overlapping cover for a hip ridge
or gable end line as the case may be. The angular
deviation of the relatively narrow edge portion 80a
and the basic body of the accessory panels 80 is chosen
so as to accommodate a general range of pitch angles
that are commonly encountered on hip and ridge roof
structures and it has been found that an angle of
approximately 45 works well on gable ends as shown
in FIG. 17. Accessory panels 80 include an outer
face which is molded to closely resemble the surface
of cedar shakes or shingle-like elements similar to
the elements 64a of the basic panels 40 and the ac
cessory panels are adapted to overlie respective
shingle-like elements 64a at the end of a basic panel
40 so as to function as a cover over a gap or edge
opening ~etween the panel end and adjacent supporting
structure to shield and cover the gap which would
otherwise ~e present along a ridge, hip, or ga~le end
line of a roof.
The unique, thin wall, molded hardboard
panels 40 are free to move or float in both vertical
and horizontal directions between upper and lower
edges and between opposite ends, respectively, after
installation and are extremely strong, even though
light in weight and even though the panels require
much lower quantity of wood hardboard material than
conventional hardboard panels, panel siding and lap
siding heretofore available for the same functional
application.
When laid up as described, the panels 40
allow air and moisture venting to occur and the unique
design of the panels permits contraction and expan-
~Z~6'~
sion of the panels in both directions in response toabsorption and desorption of moisture as weather con-
ditions change.
The panels 40 are fabricated in a hardboard
manufacturing press employing a multiplicity of press
plates arranged in pairs and contoured to provide the
intricate molded shape of the panel profile. U.S.
Patent No. 1,923,548 illustrates a multiple plate
press capable of manufacturing a number of panel blanks
in a single pressing operation. Each press cavity
comprises an upper plate having an underside or sur-
face which is shaped to replicate the molded intri-
cate design of the outer face 60 of a plurality of
panels. Customarily the press plates are dimensioned
to form panel Dlanks that are 4' wide by 16' in leng~h
and accordingly, a total of 16 panels of a 12" X 4~"
size can be made in a single pressing between each
pair of press plate~s in the press. A large press may
have a total of 20 pairs of press plates so that 20
panel blanks may be formed at each pressing.
Preferably, the molded hardboard panel blanks
are produced in a dry process and the press plates
are fabricated in an electroforming process generally
as follows. As a first step, a real wood model or
prototype of the desired panel upper surface shape is
made up using wood elements. This is done by placing
a plurality of real wood shingles and/or shakes onto
a supporting flat base in a desired pattern or arrange-
ment. The exact surface pattern that is desired to
be duplicated-in hardboard material is fashioned in a
wood model or basic prototype, and attention to detail
in every aspect is the key note. After the desired
panel surface is completed in a wood prototype, a
negative is made therefrom by casting resinous plastic
material over the desired surface of the prototype.
~764~5
-18-
When the plastic material is hardened, an exact nega-
tive duplicate of the desired surace shape is avail-
able. This plastic negative is then used as a master
negative mold for making as many positives as may be
needed, and these positives are also formed of cast
resinous plastic material. After a positive is com-
pleted, it is secured by adhesive onto a steel bac~er
plate and the surface of the positive is coated with
electroconductive, silver material. The silvered
positive on its backer plate is then submersed into
an electrolytic bath and an electrolytic process is
begun so that electro deposition of nic~le onto the
silver surface of the positive begins to taKe place.
When the thic~ness of nickle deposit is sufficient to
function as a wall for the mold or press plate, the
backer plate and positive are for the removed from
the electrolysis tank and the ~uilt up nickle material
is machined to be flat or planar in precise parallel-
ism with the surface of the bac~er plate. After this
machining is accomplished, the electro-deposited mold
is separated from the positive and backer plate and
is secured in place on another backer plate with the
machined face held tightly against the planar surface
of the plate. This new bacKer plate and mold are
then mounted on a steam cham~er in the press to func-
tion as an upper press plate of a pair of mold plates.
The bac~ or lower plate in each pair of
press plates is contoured to only generally follow
the intricate surface shape of the upper plate and
does not precisely follow the small variations in the
surface pattern of the upper plate. In order to form
a lower press plate, another negative plastic replica
of the woo~ prototype pattern is utilized. This nega-
tive functions as a vacuum mold and is provided with
a plurality of spaced apart, small diameter, drilled
12 764~
--19--
vacuum openings in the wall. A thin sheet of styrene
material approximately l/lOth o an inch thick is
drawn in closely again~t the surface of the negative
mold by drawing a vacuum through the small drilled
holes and this results in a styrene ~urface formed to
generally follow but not precisely matching that of
the negative. A bac~er plate positive is then cast
against the surface of the vacuum drawn sty~ene sheet
and this positive is coated with electro-conductive
silver material as before described and secured to a
bac~er plate for the electroly~ic process. When the
mold wall thic~ness is sufficient, the electrolytic
process is discontinued and the parallel machining
operation is accomplished in a manner similar to that
used in making an upper press plate.
Each press pla~e is mounted on a heated
plenum chamber approximately 4 inches in thic~ness
and ~he chamber is filled with super heated steam at
550 psi. Hardboard material in mat form several inches
thick is introduced into the cavity or space ~etween
each pair of spread apart or opened, upper and lower
plates. The composite wood material used ~o make
hardboard in a dry process is composed of wood chip
which are further exploded and broken down into indi-
vidual wood fibers. These fibers are heated and mixedwith phenolic resins and sized with a petroleum based,
moi~ture retarding agent such as petrolatum. The material
is then deposited onto a moving support in the form
of a thick, fluffy mat or continuous web of material
which is subsequently introduced into the spaces ~etween
open palrs of press plate~ in the press.
After introduction of the mat into all of
the cavities in the press, the pre~s plates are closed
and moved toward one another in a pressing operation
to compress the fibrous mat into a thin, molded hard-
1~6~
-20-
~oard shell having the desired pattern and profile of
the mold plate surface. Normally, the time period
during a pressing operation while the press plates
are closed may vary from between one minute and two
minutes and the temperature of the wood material of
the mat being compressed is raised during the press-
ing cycle to approximately 430 F. by the direct con-
tact with the press plates which are heated by the
super heate~ steam at 550 psi. After the pressing
cycle is completed, the press plates are opened or
spread apart and the finished molded hardboard blanks
each containing a plurality of the panels 40 are re-
moved from the press.
The surfaces of the respective upper and
lS lower press plates in each pair of press plates are
dimensioned so that the nominal thickness of the of
the thin, molded hardboard profile ~eing produced is
approximately 1/8". The press plate surfaces are
designed so that a relatively large amount of relief
or draw (from l/2" or 3/4") may be provided in the
panel when the plated are fully closed. This results
in panels 40 that appear to be much thicker ("T")
than the actual wall section thickness "t" of the
hard~oard material itself.
Panels 40 of the present invention may weigh
an average of 98 to lO0 pounds per square (100 square
feet) of surface area covered, whereas a typical as-
phalt or laminated asphalt shingle may weigh from 240
pounds up to 320 pounds per square. Conventional
hardboard panels and roofing elements that are nominal-
ly 7/16" or 1/2" in thickness may weigh as much as
250 pounds per square and real wood, thick butt cedar
shakes and shin~les may weigh considerably more than
this value, because of the high percentage of overlap
and the extra thickness and volume of material present.
~27~
-21-
Although the present invention has been
descri~ed with reference to an illustrated embodiment
thereof, it should ~e understood that numerous other
modifications and em~odiments can be made by those
skilled in t~e art that will fall within the spirit
and scope of the principles of this invention.
What is claimed as new and desired to be
secured by Let~ers Patent is:
