PRODUCTION OF COMPOSITE WOOD PRODUCT FROM USED WOOD

PRODUCTION D'UN MATERIAU COMPOSITE EN BOIS A PARTIR DE BOIS DE RECUPERATION

English Abstract

Barrel staves are recycled into a high value wood product. The longitudinally and laterally curved stave is initially trimmed along the edges to eliminate the convergency of the side edges. The stave is then split longitudinally, following the longitudinal curve of the stave. Each section of the stave is then passed through a thickness planer where the thin stave section is flattened and planed to provide two parallel surfaces. The resultant planed stave sections are flattened and adhered to a substrate as a thick veneer. The composite product can than be used for such purposes as cabinet and furniture making.

French Abstract

Des douves de tonneaux sont recyclées en un produit du bois de grande valeur. La douve courbée longitudinalement et latéralement est d'abord découpée légèrement le long des bords pour éliminer la convergence des bords latéraux. La douve est alors fendue longitudinalement, en suivant la courbe longitudinale de la douve. Chaque section de la douve passe ensuite dans une planeuse à rabotage où la section mince de la douve est aplatie et planée pour donner deux surfaces parallèles. Les sections de douve planées qui en résultent sont aplaties et collées à un substrat comme un placage épais. Le produit composite peut alors servir aux fins d'ébénisterie et de fabrication de meubles.

Claims

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CLAIMS


1. A method of producing a wood product from a barrel stave having opposite
ends,
inner and outer major surfaces extending between the ends and opposite side
edges extending between the inner and outer major surfaces, each of the inner
and
outer major surfaces having a longitudinal curvature between the ends, said
method comprising:

splitting the stave from end to end, along at least one longitudinally curved
kerf
between the inner and outer major surfaces, to produce plural longitudinally
curved stave sections;

planing each stave section to provide parallel, longitudinally curved planed
surfaces on the stave section;

deforming each stave section to a flat configuration and adhering the deformed

stave section to a substrate.

2. A method according to claim 1 for a stave with inwardly convergent side
edges,
said method including a preliminary step of cutting at least one of the side
edges
of the stave to provide a trimmed side edge and subsequently forming said
longitudinally curved kerf perpendicular to the trimmed side edge so that the
at
least one of the sides edges is neither inwardly nor outwardly convergent.



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3. A method according to claim 1 or 2 including a subsequent step of trimming
the
side edges of at least one of the stave sections and substrate.

4. A method according to claim 1, 2 or 3 comprising flattening each stave
section
during the planing step.

Description

CA 02275836 1999-06-21

PRODUCTION OF COMPOSITE WOOD PRODUCT FROM USED WOOD
FIELD OF THE INVENTION

The present invention relates to the production of a high value wood
product from waste materials, particularly barrel staves.

BACKGROUND

Barrels, particularly those use in the storage, ageing and transportation
of wines and liquors, are manufactured from high quality hardwood, especially
white
oak. Supplies of this wood for use in, for example, cabinet and furniture
making, are
limited and expensive. While it would be desirable to recycle used barrel
material for

these purposes, the barrel staves are curved both lengthwise and transversely
and
can not be trimmed to a useful flat product. The inner surface of a barrel
stave is
often charred for ageing of wines and spirits, making the inner surface
unusable for
other purposes.

The applicant has now invented a process for reclaiming this high value
wood for use, for example, in cabinetry and furniture making.

SUMMARY

According to the present invention there is provided a method of
producing a wood product from a barrel stave having opposite ends, inner and
outer
major surfaces extending between the ends and opposite side edges extending

between the inner and outer major surfaces, each of the inner and outer major
surfaces having a longitudinal curvature between the ends, said method
comprising:
splitting the stave from end to end, along at least one longitudinally

curved kerf between the inner and outer major surfaces, to produce plural
longitudinally curved stave sections;

planing each stave section to provide parallel, longitudinally curved
planed major surfaces;


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deforming each section to a flat configuration and adhering the
deformed section to a substrate.

Splitting the stave lengthwise, preferably in two, produces thinner stave
sections that are, unlike the full stave, sufficiently flexible that they may
be pressed
flat. This may be done during planing, using the pressure rollers of a
thickness

planer. When the resultant stave section is flattened and glued to a flat
substrate, a
composite article ready for use is produced. The substrate may be another type
of
wood, a wood product for example particle board or plywood, or any other
suitable
substrate.

The longitudinal splitting of the staves is preferably carried out using a
band saw in order to follow the longitudinal contour of the stave. As a
preliminary
step, one or both edges of the stave may be cut off to provide a flat surface
perpendicular to the longitudinal cut for supporting the stave on the table of
the band
saw.

Once the stave section has been laminated onto the substrate, side
edges of the compound product may be trimmed as necessary to provide a
parallel
sided product with the desirable high quality wood covering one complete
surface.
BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings, which illustrate an exemplary
embodiment of the present invention:

Figure 1 is an isometric view illustrating a barrel stave;
Figure 2 is a transverse cross section of the stave;
Figure 3 is a longitudinal cross section of the stave;

Figure 4 is a transverse cross section showing an edge trimming step;
Figure 5 is a transverse cross section showing the longitudinal splitting
of the stave;


CA 02275836 2006-12-01
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Figure 6 is a longitudinal cross section illustrating the planning of a strip
section;
Figure 7 is an elevation showing the laminating of the stave section to a
substrate;
and

Figure 8 is a plan view illustrating edge trimming of the composite article
formed
by the stave section and the substrate.

DETAILED DESCRIPTION

Referring to the accompanying drawings, Figure I illustrates a barrel stave
10.
The stave has two opposite ends 12. It has two major faces, an inner face 14
that is
concave and outer face 16 that is convex. Extending between the inner and
outer faces

are side edges 18. These edges are convex from end to end and converge from
the outer
face towards the inner face. In many cases the inner face 14 of the barrel is
charred and
the barrel stave has a relatively high moisture content, particularly if it
has been used in
the recent past for containing a liquid. As discussed above, barrel staves of
this sort are
commonly made from white oak, a material which is of very high value for
furniture and
cabinet making.

Before processing the barrel stave, it is preferably dried to a suitable
moisture
level for workability, preferably below 18% moisture.

The first step in processing the barrel is illustrated in Figure 4. This
involves
trimming the side edges 18 to remove in the inwards taper of the stave. This
is
conveniently done using a band saw, trimming about one quarter inch off each
edge of
the stave.

The next step is splitting the stave in two lengthwise, as illustrated in
Figure 5.
The center kerf 22 extends from edge to edge perpendicular to the trimmed
edges. The
cut is made with a band saw with on of the trimmed edges supported on the
table 24 of
the saw. The kerf 22 follows the longitudinal contour of the stave. This


CA 02275836 1999-06-21

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produces an inner section 26 and an outer section 28 of the stave.

In the following step, the stave section is passed through a thickness
planer 30. The planer is conventional. It includes a set of pressure rollers
32 for
pressing a workpiece against a bed 34 and upper and lower planer heads 36 for

planing parallel surfaces on the workpiece as it passes through the planer. As
the
curved stave section passes through the planer, the rollers 32 press it flat
against the
planer bed. This removes any charcoal on the inner face and yields a planed
inner
face 38 and a planed outer face 40. The stave section is at this point
approximately
one quarter inch thick and 30 inches long.

As illustrated in Figure 7, a substrate 42 is covered with a layer of
adhesive 44 and the planed workpiece is laminated to the substrate. Pressure
is
applied to the composite using a hydraulic press (not illustrated) with a base
plate 46
supporting the substrate 42 and a top plate 48 pressing the stave section
against the
substrate. This yields a composite panel 50 with the stave section laminated
to the

top surface of the substrate. The side edges of this composite article may
then be
trimmed along parallel cut lines 52 as shown in Figure 8 to yield a parallel
sided
product with a thick surface veneer of sound white oak.

While one particular embodiment of the present invention has been
described in the foregoing, it is to be understood that other embodiments are
possible
within the scope of the invention and are intended to be included herein. The
invention is to be considered limited solely by the scope of the appended
claims.

Representative Drawing