U.S. patent application number 11/223208 was filed with the patent office on 2006-03-16 for value extraction from harvested trees and related laminates and processes.
Invention is credited to Warwick Bosson.
Application Number | 20060054267 11/223208 |
Document ID | / |
Family ID | 32986081 |
Filed Date | 2006-03-16 |
United States Patent
Application |
20060054267 |
Kind Code |
A1 |
Bosson; Warwick |
March 16, 2006 |
Value extraction from harvested trees and related laminates and
processes
Abstract
A laminate of laminae of uniform rectangular cross-sections or
depths and lengths arranged randomly or otherwise in the laminate,
such laminae having been derived from a feedstock comprising a
population of logs (single or multigrade) wherein the population of
laminae comprises all of the laminae that can be derived from the
population of logs (exclusive only of laminae or material for
laminae that are not of acceptable rectangular cross-section and/or
length), and where each cross-section of each lamina represents a
maximum of one thirtieth of the log cross-section, or the thickness
of each lamina represents a maximum of one fifteenth of the small
end log diameter.
Inventors: |
Bosson; Warwick; (Auckland,
NZ) |
Correspondence
Address: |
JACOBSON HOLMAN PLLC
400 SEVENTH STREET N.W.
SUITE 600
WASHINGTON
DC
20004
US
|
Family ID: |
32986081 |
Appl. No.: |
11/223208 |
Filed: |
September 12, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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PCT/NZ04/00053 |
Mar 10, 2004 |
|
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11223208 |
Sep 12, 2005 |
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Current U.S.
Class: |
156/64 ;
156/296 |
Current CPC
Class: |
Y10T 156/1059 20150115;
Y10T 428/2457 20150115; B27M 3/006 20130101; B27M 1/08 20130101;
Y10T 156/1075 20150115; Y10T 156/10 20150115; Y10T 428/31989
20150401; E04C 3/122 20130101 |
Class at
Publication: |
156/064 ;
156/296 |
International
Class: |
B32B 37/00 20060101
B32B037/00; B29C 65/00 20060101 B29C065/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 10, 2003 |
NZ |
524672 |
Claims
1. A laminate of laminae, each lamina having been derived from a
feedstock comprising a population of logs (single or multigrade),
each cross-section or depth of each lamina being uniform and
representing a maximum of one twentieth of the log cross-section or
the thickness of each lamina being not more than one fifteenth of
the small end log diameter, and arranged with a profiled array of
their properties in the laminate.
2. The laminate of claim 1 wherein each lamina represents a maximum
of one thirtieth of the log cross-section.
3. The laminate of claim 1 which is engineered structural timber
and the profiling has been with respect to strength and/or
stiffness.
4. The laminate of claim 1 wherein the profiling has been with
respect to appearance thereby to maximise the external
appearance.
5. The laminate of claim 3 when prepared by reliance upon variation
of structural properties within a tree stem and between stems in a
forest resource by having broken down logs into at least 20 thin
boards or sticks per log to ensure for the laminate a mean
structural performance at least 10% higher than milled lumber, a
lowest structural property (90% confidence) of approximately twice
that from milled lumber, and/or a very low or zero incidence of
critical defects.
6. The laminate of claim 5 wherein each log has been broken down
into 30 or more thin boards or sticks.
7. The laminate of claim 4 wherein there has been reliance upon
sufficient variation of appearance properties within a tree stem
and between stems in a forest resource by having broken log down
into 15 or more thin boards or sticks per log, scanned for
appearance properties, sorted into like properties and judicially
reassembled by laminating edge gluing and finger jointing so as to
provide a yield at least twice that of comparable appearance grade
lumber that resource would have otherwise made available from
milled lumber.
8. The laminate of claim 7 wherein each log has been broken down
into 20 or more thin boards or sticks.
9. The laminate of claim 1 wherein there is end-joined sticks
throughout the laminate.
10. A method of producing engineered "structural" lumber which
comprises or includes the steps of deriving thin boards at uniform
laminar thickness (hereafter "sticks") from a feedstock of single
forest or multiple forest derived single or multi grade logs,
drying the sticks at least to some extent, (optionally) taking each
stick to its substantially finished width by any suitable means,
testing or assessing each stick for at least one structural
property and streaming them as a result of such testing or
assessing, endwise joining sticks of each stream and of finished
width to at least the length of the lumber to be engineered,
laminating the endwise joined sticks and/or sticks from a plurality
of streams so as to provide an appropriate strength and/or
stiffness profile to achieve the desired strength and/or stiffness
characteristic required for the engineered lumber.
11. The method of claim 10 wherein the thin boards are of uniform
laminar thickness.
12. The method of claim 10 wherein a minimum of 30 sticks per log
cross-section are obtained to expose a broad range of
properties.
13. The method of claim 10 wherein prior to laminating the endwise
joined sticks and/or sticks have been cut to customer length.
14. The method of claim 10 wherein the length of each stick is from
0.5 to 2.4 metres.
15. The method of claim 14 wherein the length of each stick is from
1.2 to 2.4 metres.
16. The method of claim 14 wherein the length of each stick is from
0.5 to 1.2 metres.
17. A method of producing an engineered "appearance" lumber which
comprises or includes the steps of deriving thin boards of uniform
lamina thickness (hereafter "sticks") from a feedstock of single
forest or multiple forest derived single and/or multi grade logs,
drying the sticks at least to some extent, (optionally) taking each
stick to clean width increment by any suitable means, assessing
each board for appearance and streaming by appearance property and
width increment for endwise joining of sticks, endwise joining
sticks to at least the length of the lumber to be engineered, panel
forming to at least a desired width the endwise joined sticks,
forming boards of desired width from the panel or panels, and
laminating boards thus formed (optionally with others) so as to
provide an appropriate exterior appearance for the engineered
lumber.
18. The method of claim 17 wherein the sticks are derived with a
uniform laminar thickness.
19. The method of claim 17 wherein each stick has a maximum
thickness one fifteenth ( 1/15) or less of the small end diameter
of the log(s).
20. The method of claim 17 wherein the length of each stick is from
0.5 to 2.4 metres.
21. The method of claim 20 wherein the length of each stick is from
1.2 to 2.4 metres.
22. The method of claim 20 wherein the length of each stick is from
0.5 to 1.2 metres.
23. The method of claim 17 wherein the sticks and/or endwise joined
sticks have been cut to a customer length prior to lamination.
24. The method of claim 17 wherein better appearance boards are to
the outside of the transverse section of the main faces of the
laminated product.
25. A method of producing an engineered "appearance" lumber which
comprises or includes the steps of deriving thin boards of uniform
lamina thickness (hereafter "sticks") from a feedstock of single
forest or multiple forest derived single and/or multi grade logs,
drying the sticks at least to some extent, (optionally) taking each
stick to clean width increment by any suitable means, assessing
each board for appearance and streaming by appearance property,
panel forming to at least a desired width the sticks of common
grade, forming boards of desired width from the panel or panels,
endwise joining the boards to at least the length of the lumber to
be engineered, and laminating boards thus formed (optionally with
others) so as to provide an appropriate exterior appearance for the
engineered lumber.
26. The method of claim 25 wherein the sticks are derived with a
uniform laminar thickness.
27. The method of claim 25 wherein each stick has a maximum
thickness one fifteenth ( 1/15) or less of the small end diameter
of the log(s).
28. The method of claim 25 wherein the length of each stick is from
0.5 to 2.4 metres.
29. The method of claim 28 wherein the length of each stick is from
1.2 to 2.4 metres.
30. The method of claim 28 wherein the length of each stick is from
0.5 to 1.2 metres.
31. The method of claim 25 wherein the sticks and/or endwise joined
sticks have been cut to a customer length prior to lamination.
32. The method of claim 25 wherein better appearance boards are to
the outside of the transverse section of the main faces of the
laminated product.
33. An elongate engineered timber product having a laminated
transverse substantially rectangular or square cross section
transverse to the longitudinal axis, wherein the cross section (a)
in one of its major or minor axes is co-extensive with the
transverse width parallel to that same axis of each lamina. and (a)
in the other of its major or minor axes, has the accumulated
thicknesses of the individual lamina, and wherein each or any
lamina is over the length of the product either (I) a unitary stick
from a log, or (II) an endwise (e.g. finger jointed, lap jointed,
and/or other such jointed) joined structure of at least two sticks
("stick components") from a log or logs, and has the grain of its
stick or stick components running at least substantially
longitudinally of said longitudinal axis, and wherein there has
been a profiling of laminae strength and/or stiffness
characteristics across that transverse axis of accumulated
thickness thereby to engineer a strength and/or stiffness
characteristic of the product in planes normal to such
thicknesses.
34. An elongate engineered timber product having a laminated
transverse substantially rectangular or square cross section
transverse to the longitudinal axis, wherein the cross section (a)
in one of its major or minor axes is co-extensive with the
transverse width parallel to that same axis of each lamina. and (b)
in the other of its major or minor axes, has the accumulated
thicknesses of the individual lamina, and wherein each or any
lamina is over the length of the product either (I) a unitary stick
from a log, or (II) an endwise (e.g. finger jointed, lap jointed,
and/or other such jointed) joined structure of each at least two
sticks ("stick components") matched as to strength and/or stiffness
from a log or logs, and has the grain of its stick or stick
components running at least substantially longitudinally of said
longitudinal axis, and wherein there has been a profiling of
laminae strength and/or stiffness characteristics across that
transverse axis of accumulated thickness thereby to engineer a
strength and/or stiffness characteristic of the product in planes
normal to such thicknesses, such profiling having the effect of at
least emphasising the presence of stronger and/or stiffer sticks to
the outside of the transverse section.
35. An elongate engineered timber product made to length L and
having a laminated transverse substantially rectangular or square
cross section transverse to the longitudinal axis, wherein the
cross section (a) in one of its major or minor axes is co-extensive
with the transverse width parallel to that same axis of each
lamina. and (b) in the other of its major or minor axes, has the
accumulated thicknesses of the individual lamina, and wherein at
least most laminae over the length L of the product are an endwise
(e.g. finger jointed, lap jointed, and/or other such jointed)
joined structure of sticks derived from a log resource with the
grain of its stick components running at least substantially
longitudinally of said longitudinal axis, and wherein there has
been a profiling of laminae strength and/or stiffness
characteristics across that transverse axis of accumulated
thickness thereby to engineer a strength and/or stiffness
characteristic of the product in planes normal to such
thicknesses.
36. An elongate engineered timber product made to length L and
having a laminated transverse substantially rectangular or square
cross section transverse to the longitudinal axis, wherein the
cross section (a) in one of its major or minor axes is co-extensive
with the transverse width parallel to that same axis of each
lamina. and (b) in the other of its major or minor axes, has the
accumulated thicknesses of the individual lamina, and wherein at
least a sufficient number of the laminae is over the length L of
the product are an endwise (e.g. finger jointed, lap jointed,
and/or other such jointed) joined structure, each of longitudinally
aligned and matched as to strength and/or stiffness, sticks derived
from log resource(s). and wherein there has been a profiling of
streamed laminae already endwise joined of total length of at least
L across that transverse axis of accumulated thickness thereby
reliant on stronger and/or stiffer laminae being placed to the
outside to engineer a strength and/or stiffness characteristic of
the product in planes normal to such thicknesses.
37. An elongate engineered timber products wherein each product
having a laminated transverse substantially rectangular or square
cross section transverse to its longitudinal axis, and wherein the
cross section of each product (a) in one of its major or minor axes
is co-extensive with the transverse width parallel to that same
axis of each lamina. and (b) in the other of its major or minor
axes, has the accumulated thicknesses of the individual lamina, and
wherein at least some laminae over the length of each product is an
endwise (e.g. finger jointed, lap jointed, and/or other such
jointed) joined structure of sticks, each such stick being derived
from a log, and wherein using a sufficient log resource laminae
strength and/or stiffness characteristics have been profiled across
that transverse axis of accumulated thickness thereby to engineer
for each product a strength and/or stiffness characteristic of each
of the products in planes normal to such thicknesses.
38. An elongate engineered timber product of length L having a
laminated transverse substantially rectangular or square cross
section transverse to the longitudinal axis, wherein the cross
section (a) in one of its major or minor axes is co-extensive with
the transverse width parallel to that same axis of each lamina. and
(b) in the other of its major or minor axes, has the accumulated
thicknesses of the individual lamina, and wherein at least some
laminae over the length L of the product is an endwise (e.g. finger
jointed, lap jointed, and/or other such jointed) joined structure
of sticks ("stick components") of length much less than L derived
from log resources, and wherein there has been a profiling of
laminae characteristics across that transverse axis of accumulated
thickness thereby to best face the outside of the product on the
opposed faces not showing the accumulated thicknesses, and wherein
each said endwise joined structure has been of at least length L
prior to lamination and with at least some having been to a length
greater than L.
39. A method of deriving an elongate laminate product from a tree
or logs thereof, said method comprising or including (I) deriving
logs of short length and/or of a variety of lengths, (II)
(optionally) profiling longitudinally at least part of the
periphery of each log, (III) longitudinally breaking such log
lengths or at least part profiled logs down to boards, such
breakdown to boards at least predominantly deriving surfaces
defined by a longitudinal splitting and/or sawing (although at
least one or some of the surfaces of each or some boards can be
optionally dressed surfaces), (IV) drying the boards, (V) endwise
finger jointing at least some of the dried boards (optionally after
dressing to width) i. of similar or the same transverse dimensions
and ii of like characteristics (e.g. selected from some assessment
of at least one of the characteristics selected from the group of
stiffness, strength and appearance) in order to derive boards of
greater length (e.g. to at least customer length), and iii
laminating such boards to derive a laminated elongate product, such
lamination being to provide both or either (i) a structural member
(e.g. beam, stud, etc.) having greater transverse dimension or
bending resistance, or both, in a plane normal to the plane or
planes of lamination rather than parallel thereto, boards of known
characteristics being substantially optimally positioned in the
laminated section, and/or (ii) a structural or other member having
its greater transverse dimension parallel to the laminating plane
or planes (and, optionally, having one exposed face of greater
transverse dimension as an appearance face), boards of known
characteristics being substantially optimally positioned in the
laminated
40. A method of deriving an elongate laminate product from a tree,
said method comprising or including scanning tree stems and/or logs
after debarking and deriving log lengths of lower value tree stem
regions that are substantially defect free, [the logs being at
least mainly from 0.5 m to 2.4 m in length], profiling at least in
part the exterior of each log, longitudinally breaking such at
least in part profiled log lengths down to boards reliant as a
datum on at least part of the log profiling, such breakdown at
least predominantly deriving surfaces of the boards defined
predominantly by a longitudinal splitting and/or sawing, drying the
boards, and both or either: (A) inspecting, scanning and/or grading
the boards [before and/or after, optionally trimming at least one
side of some or all boards to extent required to match boards for
transverse section and/or to customer width], endwise finger
jointing at least some of the boards of the same or substantially
same transverse dimensions, and optionally substantially same
grade, to assemble an elongated composite board [and, if necessary,
prior to or post lamination transversely cutting the elongated
composite board in order to derive boards to customer length], and
laminating such boards in a process to derive an elongate laminate
product of customer length, such lamination being to provide a
structural member (e.g. beam, stud, etc.) having by appropriate
placement of different characteristics in the laminate a desired
structural performance, (B) inspecting, scanning and/or grading the
boards, [before and/or after optionally trimming at least one side
of some or all boards to extent required to match boards for
transverse section and/or to customer width], endwise finger
jointing at least some of the transversely dimensioned boards of
the same or substantially same transverse dimensions, and
optionally substantially same grade, to assemble an elongated
composite board [and, if necessary, prior to or post lamination
transversely cutting the elongate composite board in order to
derive boards to customer length], and laminating such boards in a
process to derive an elongate laminate product of customer length,
such lamination being to provide a structural or other member
having its greater transverse dimension parallel to the laminating
plane or planes and having one exposed face of greater transverse
dimension as an appearance face.
41. A laminate of laminae of uniform rectangular cross-sections or
depths and lengths arranged randomly in the laminate, such laminae
having been derived from a feedstock comprising a population of
logs (single or multigrade) wherein the population of laminae
comprises all of the laminae that can be derived from the
population of logs (exclusive only of laminae that are not of
acceptable rectangular cross-section and/or length), and where each
cross-section of each lamina represents a maximum of one twentieth
of the log cross-section, or the thickness of each lamina
represents a maximum of one fifteenth of the small end log
diameter.
42. The laminate of claim 41 wherein each lamina represents a
maximum of one thirtieth of the log cross-section.
43. The laminate of claim 42 wherein at least some of the laminae
result from streaming of endwise joined parts thereof.
44. The laminate of claim 42 wherein no substantial pith content is
in outside laminae.
45. A laminate of laminae of uniform rectangular cross-sections or
depths and lengths arranged randomly or otherwise in the laminate,
such laminae having been derived from a feedstock comprising a
population of logs (single or multigrade) wherein the population of
laminae comprises all of the laminae that can be derived from the
population of logs (exclusive only of laminae or material for
laminae that are not of acceptable rectangular cross-section and/or
length), and where each cross-section of each lamina represents a
maximum of one twentieth of the log cross-section, or the thickness
of each lamina represents a maximum of one fifteenth of the small
end log diameter.
46. The laminate of claim 45 wherein each lamina represents a
maximum of one thirtieth of the log cross-section.
Description
TECHNICAL FIELD
[0001] The present invention relates to value extraction from tree
stem materials (without any reduction to discrete fibre form) (i.e.
from tree stem lengths) so as to provide engineered structural
products and/or appearance products (e.g. laminates) which,
especially when from lower valued material and/or lower valued logs
of a tree stem, will represent lumber value enhancement.
BACKGROUND ART
[0002] Traditionally, dimensional lumber is produced for two main
purposes: [0003] "Structural" lumber is produced and graded for
properties of strength and stiffness. "Early Wood" (core wood) has
lower basic properties than "Late wood" and inclusion of "Early
Wood" in a piece of dimensional lumber can cause strength down
grading. Defects, (knots, resin pockets, bark inclusions, decay,
insect attack, shakes, etc.) also lead to down grading although in
pine knots have the dominant influence. These defects tend to be
scattered through the length of a piece of lumber and lead to down
grading on the basis of "a piece is only as strong as the weakest
link". [0004] "Appearance" lumber is produced and selected on the
basis of surface appearance. Appearance grades can range from
"Clears" for furniture type end uses to "merchantable" for exterior
finishing. The important features are lack of defects particularly
those that affect the surface finish. Inter-grown knots do not
result in a down grade and for unpainted surfaces can be considered
an attractive feature.
[0005] For any particular feedstock (log grade) and cutting regime
a wide range of properties will be produced. The total output can
be tested and graded or inspected and graded after initial sawing.
Even within grades there is a wide range of properties.
[0006] This range of properties is produced when a log is broken
down into (typically 100.times.50 mm) sections. If a log is broken
down into even smaller sections (say 50.times.7 mm) we have found
there will be a greater spread of properties.
[0007] With traditional dimensional lumber the output range is
predominantly influenced by selection of feedstock (tree age,
position in the tree, silver-culture regime) although there is some
minor influence from the sawing patterns selected.
[0008] Examples of efforts in the past to meet demand for products
other than pulp and paper have included dry fibre separation and
reconstitution procedures as typified by U.S. Pat. No. 4,061,819
(Barnes). (MacMillan Bloedel Ltd) and LSL and LVL procedures as
used by Trus Joist Corporation of Boise, Id., USA.
[0009] Weyerhaeuser Company PCT/US98/11566 (WO98/56549) discloses
composite lumber products based on sweep avoiding slat production
from flitches derived from round logs.
[0010] MacMillan Bloedel Limited in NZ 241289 (also referring
Holman U.S. Pat. No. 4,255,477 in respect of panel or strand lumber
products and U.S. Pat. Nos. 4,610,913 and 4,751,131 of Barnes in
respect of the use of longer wafers in higher strength lumber
product production) discloses composite wood products of improved
strength where cutting avoids surface and internal damage to the
veneer, wafers and strands.
[0011] Weyerhaeuser Company PCT/US97/15250 (WO98/10157) discloses
engineered structural wood products and related methods reliant on
different rectangular board orientations in the resultant laminated
product.
[0012] U.S. Pat. No. 5,500,070 (Traben et al) discloses knife
cutting of thin boards for the purpose of manufacturing
multilayered laminated products.
[0013] Nevertheless efficiencies of usage while still providing
acceptable engineered lumber products especially to customer demand
can still further be improved where source materials are single or
multi forest derived single or multi grade logs.
[0014] The present invention as an object or an alternate object
addresses issues of waste reduction during the production of
dimensional lumber and in so doing preferably improves usage of
feedstock for the purpose of value enhancement.
[0015] The present invention has as one or one alternative object a
method of producing laminated elongate products and to related
products, practices and procedures reliant on a performance
advantage over mere random assembly.
[0016] The present invention has as one or an alternative object an
overall process capable of better using logs or part of tree stems
(and particularly those of conifers such as Radiata Pine, Loblolly
Pine, Douglas Fir, Spruce, etc.) which might otherwise only be
suitable for chipping or non structural or non appearance
lumber.
[0017] Another or an alternative object therefore, as will become
apparent, is the conversion of low grade wood into high grade
products preferably at an efficient yield from trees.
DISCLOSURE OF INVENTION
[0018] We believe there is sufficient variation of structural
properties within a tree stem and between stems in a forest
resource that when the logs are broken down into 30 or more thin
boards per log, tested for structural properties, sorted into like
properties and judicially re-assembled by laminating then the
resultant lumber will [0019] have mean structural performance at
least 10% higher than conventionally produced lumber (See FIG. 24
hereafter), [0020] have a lowest structural property (90%
confidence) of approximately twice that from conventionally
produced lumber (See FIG. 24 hereafter), [0021] have a very low or
zero incidence of critical defects.
[0022] We believe there is sufficient variation of appearance
properties within a tree stem and between stems in a forest
resource that when the logs are broken down into 15 or more thin
wide boards per log (where the thickness is less than one fifteenth
of the Small End Diameter "SED"), scanned for appearance
properties, sorted into like properties and judicially re-assembled
by laminating edge gluing and finger jointing then the resultant
lumber will [0023] yield at least twice and we estimate at least
approximately 3 times the appropriate appearance grade from that
resource as would otherwise be available from conventional sawn
lumber.
[0024] The present invention is a novel advancement on the
traditional methods of producing dimensional lumber as it takes
advantage of the following: [0025] 1. Breakdown of logs into many
small parts (preferably a minimum of 30 parts per log
cross-sectional all of equal thickness) and random assembly by
lamination provides the opportunity to randomise any defects and
limit their influence on strength or appearance characteristics,
thus improving the average performance over traditional dimensional
lumber. [0026] 2. Breakdown into many small parts reveals the
statistical spread of strength and appearance properties inherent
within a log and between any group of logs. Grading, sorting and
streaming these parts can significantly improve the performance of
the assembled finished product over and above the improvements from
random assembly. [0027] 3. We contend that there is sufficient high
strength board extraction derivable from on low value upper log
forming regions of a tree, or immature trees, or from short logs
(normally wasted), or from logs with excessive taper or bend which
can be reduced to short logs as feed stock for this process,
especially provided an effective process provides both high yield
and does not involve any mandatory substantial encroachment into
materials extracted from high value lowermost logs of the tree.
Such encroachment can nevertheless be allowed as and when
wanted.
[0028] The process envisages the breaking of a log into small
(preferably rectangular) sections, grading these sections
(preferably once dry) and assembling these in accordance with the
invention into an improved product.
[0029] As well, by the inherent nature of the process, the precise
dimensions the customer wants can be produced. Also because the
output is laminated it will have good dimensional stability. These
features also have considerable value to the customer.
[0030] The process of the present invention breaks down logs into
specific component parts (i.e. thin boards) (e.g. hereinafter
"sticks") to provide a large population of parts (i.e. many parts
from many logs) exhibiting a wide range of properties
strength/stiffness/appearance which at the discretion of the
processor (preferably with (a) end jointing and/or (b)
determination and/or assessment) are streamed to produce a high
proportion of superior laminates as products from a small
proportion of superior strength or appearance parts.
[0031] As used herein "stick" or "sticks" refers to thin boards
whether trimmed for length or otherwise trimmed to reduce
distortions and/or blemishes.
[0032] As used herein "boards" includes but preferably means
rectangular or square sectioned boards. Such boards of any length
(usually between 0.5 m to 2.4 m in length) may post drying require
some trimming to a dimensional lumber width.
[0033] As used herein "engineered" in respect of product or boards
means or includes fabricated and/or laminated.
[0034] As used herein "sections" or "small sections" means or
includes preferably smaller rectangular sections preferably of
lamina thickness.
[0035] As used herein "stem" or "stems" refers to any trunk and/or
branch.
[0036] As used herein "drying" involves any suitable process
whereby "green" wood is brought to a state of dryness (e.g. 200% to
<12% w/w).
[0037] As used herein "splitting" includes a process typified by
that of Linck disclosed at its website www.linck-hvt.com or in any
of its patents referred to herein.
[0038] As used herein "customer" in respect of length, width or any
other dimension or appearance means that required by a wholesaler,
retailer or end user whether to be cut further or not.
[0039] As used herein "grading/assessing" is any machine, optical
or manual procedure to determine structural and/or strength and/or
stiffness and/or appearance characteristics.
[0040] As used herein "and/or" means "and" or "or".
[0041] As used herein "(s)" following a noun includes the singular
and plural forms of the noun.
[0042] Reference to "streaming", etc. means streaming into at least
two streams (e.g. preferably from 4 to 8 but can be more or
less).
[0043] In one aspect the invention is a laminate of laminae (e.g as
engineered structural and/or appearance lumber preferably made to
length), each lamina having been derived from a feedstock
comprising a population of logs (single or multigrade), each
cross-section of each lamina being uniform at least insofar as
depth and representing a maximum of one twentieth of the log
cross-section for structural products or each lamina having a
thickness not greater than one fifteenth of SED for wide appearance
lamina, and arranged with a profiled array of their properties in
the laminate.
[0044] Preferably each lamina represents a maximum of one thirtieth
of the log cross-section.
[0045] Preferably breakdown from logs is in a pattern to minimise
spike knots.
[0046] Preferably the total breakdown is or has been to effect, as
far as is practical, a maximising of the spread of properties
amongst laminae ["sticks"].
[0047] Preferably the cutting of each stick is or has been from a
minimum number of growth years as is practical.
[0048] The laminate has been made to specification.
[0049] Where the laminate is engineered structural timber, the
profiling has been with respect to strength and/or stiffness [e.g
by reference to Modulus of Elasticity [MOE] or other measure or
assessment].
[0050] Where the laminate is engineered appearance lumber the
profiling has been with respect to appearance thereby to maximise
the external appearance especially on one side.
[0051] The laminate preferably has been prepared by reliance upon
variation of structural properties within a tree stem and between
stems in a forest resource such as, in the case of engineered
structural timber, the logs have been broken down into at least 20
[preferably 30 or more] thin boards or sticks per log preferably to
ensure a mean structural performance between 10 and 20% higher than
milled lumber, and/or having a lowest structural property (90%
confidence) of approximately twice that of milled lumber, and/or
having a very low or zero incidence of critical defects.
[0052] Preferably there has been reliance upon sufficient variation
of appearance properties within a tree stem and between stems in a
forest resource, where the logs have been broken down into at least
15 [preferably 20 or more] thin boards or sticks per log, scanned
for appearance properties, sorted into like properties and
judicially reassembled by (in any order) laminating, edge gluing
and finger jointing preferably so as to provide a yield at least
twice that of comparable appearance grade lumber that resource
would have otherwise made available from milled lumber.
[0053] In another aspect the invention is a method of producing
engineered "structural" lumber which comprises or includes the
steps of [0054] deriving thin boards at uniform laminar thickness
(hereafter "sticks") from a feedstock of single forest or multiple
forest derived single or multi grade logs (preferably a minimum of
at least 20, but more preferably of at least 30 sticks, per log
cross-section to expose a broad range of properties), [0055] drying
the sticks at least to some extent, [0056] (optionally) taking each
stick to its substantially finished width by any suitable means,
[0057] testing or assessing each stick for at least one structural
property and streaming them as a result of such testing or
assessing, [0058] endwise joining sticks of each stream and of
finished width to at least the length of the lumber to be
engineered, [0059] laminating the endwise joined sticks and/or
sticks from a plurality of streams so as to provide an appropriate
strength and/or stiffness profile to achieve the desired strength
and/or stiffness characteristic required for the engineered
lumber.
[0060] Preferably the sticks are of uniform laminar thickness.
[0061] Preferably a minimum of 30 sticks per log cross-section are
obtained to expose a broad range of properties.
[0062] Preferably prior to laminating the endwise joined sticks
and/or sticks have been cut to customer length. The length of each
stick or stick sequence is from 0.5 to 2.4 metres. Whilst the
length can be 1.2 to 2.4 metres, preferably the length of each
stick is from 0.5 to 1.2 metres.
[0063] In another aspect the invention consists in a method of
producing an engineered "appearance" lumber which comprises or
includes the steps of [0064] deriving thin boards of uniform lamina
thickness (hereafter "sticks") from a feedstock of single forest or
multiple forest derived single and/or multi grade logs (preferably
a maximum thickness one fifteenth ( 1/15) of small end diameter to
expose the range of properties), [0065] drying the sticks at least
to some extent, [0066] (optionally) taking each stick to clean
width increment by any suitable means, [0067] assessing each board
for appearance and streaming by appearance property and width
increment for endwise joining of sticks, [0068] endwise joining
sticks to at least the length of the lumber to be engineered,
[0069] panel forming to at least a desired width the endwise joined
sticks, [0070] forming boards of desired width from the panel or
panels, and [0071] laminating boards thus formed (optionally with
others) so as to provide an appropriate exterior appearance for the
engineered lumber.
[0072] Preferably sticks are derived with a uniform laminar
thickness.
[0073] Preferably each stick has a maximum thickness one fifteenth
( 1/15) or less of the small end diameter of the log(s).
[0074] The length of each stick is from 0.5 to 2.4 metres. Whilst
it can be preferably the length of each stick is from 0.5 to 1.2
metres.
[0075] The sticks derived from a population of logs and hence the
laminae incorporated into the corresponding population of laminates
would be of uniform thickness with the thickness preferably being
chosen prior to breakdown of the logs. Such thickness preferably
would be not less than 4 mm and not greater than 17 mm.
[0076] The aforesaid range ensures a thickness can be chosen that
is amenable to the production and processing of sticks, while
ensuring an adequate number of sticks can be produced to reveal the
spread of properties and ensure a laminate will comprise at least 3
laminae for an appearance product and preferably at least 4 laminae
for a structural product.
[0077] In practice the chosen thickness would normally be between 6
mm and 11 mm.
[0078] Preferably breakdown from logs is in a pattern to minimise
spike knots.
[0079] Preferably the total breakdown is or has been to effect, as
far as is practical, a maximising of the spread of properties
amongst lamina ["sticks"].
[0080] Preferably the cutting of each stick is or has been from a
minimum number of growth years as is practical.
[0081] The sticks derived from a population of logs and hence the
laminae incorporated into the corresponding population of laminates
would be of uniform thickness with the thickness preferably being
chosen prior to breakdown of the logs. Such thickness preferably
would be not less than 4 mm and not greater than 17 mm.
[0082] The aforesaid range ensures a thickness can be chosen that
is amenable to the production and processing of sticks, while
ensuring an adequate number of sticks can be produced to reveal the
spread of properties and ensure a laminate will comprise at least 3
laminae for an appearance product and preferably at least 4 laminae
for a structural product.
[0083] In practice the chosen thickness would normally be between 6
mm and 11 mm.
[0084] In another aspect the invention consists in a method of
producing an engineered "appearance" lumber which comprises or
includes the steps of [0085] deriving thin boards of uniform lamina
thickness (hereafter "sticks") from a feedstock of single forest or
multiple forest derived single and/or multi grade logs, [0086]
drying the sticks at least to some extent, [0087] (optionally)
taking each stick to clean width increment by any suitable means,
[0088] assessing each board for appearance and streaming by
appearance property, [0089] panel forming to at least a desired
width the sticks of common grade, [0090] forming boards of desired
width from the panel or panels, [0091] endwise joining the boards
to at least the length of the lumber to be engineered, and [0092]
laminating boards thus formed (optionally with others) so as to
provide an appropriate exterior appearance for the engineered
lumber.
[0093] Preferably the sticks are derived with a uniform laminar
thickness.
[0094] Preferably each stick has a maximum thickness one fifteenth
( 1/15) or less of the small end diameter of the log(s).
[0095] Preferably the length of each stick is from 0.5 to 2.4
metres.
[0096] Preferably the length of each stick is from 1.2 to 2.4
metres.
[0097] Preferably the length of each stick is from 0.5 to 1.2
metres.
[0098] Preferably the sticks and/or endwise joined sticks have been
cut to a customer length prior to lamination.
[0099] Preferably better appearance boards are to the outside of
the transverse section of the main faces of the laminated
product.
[0100] In another aspect the present invention consists in a method
of producing engineered "structural" lumber which comprises or
includes the steps of [0101] deriving thin boards at laminar
thickness (hereafter "sticks") from a feedstock of single forest or
multiple forest derived single and/or multi grade logs, [0102]
drying the sticks at least to some extent, [0103] (optionally)
taking each stick to its finished width by any suitable means,
[0104] testing or assessing each stick for at least one structural
property and as a result of such testing or assessing, streaming
them [0105] endwise joining sticks of each stream and of finished
width to at least the length of the lumber to be engineered, [0106]
laminating the endwise joined sticks and/or sticks from a plurality
of streams thereof so as to provide an appropriate strength and/or
stiffness profile to achieve the desired strength and/or stiffness
characteristic required for the engineered lumber.
[0107] Preferably the sticks and/or endwise joined sticks have been
cut to a customer length prior to lamination.
[0108] Preferably higher strength and/or stiffness sticks are to
the outside of the transverse section of the laminated product.
[0109] Preferably any one or more of the features of the system is
substantially as hereinafter described with reference to any one or
more of the accompanying drawings.
[0110] In yet a further aspect the present invention consists in a
method of producing an engineered "appearance" lumber which
comprises or includes the steps of [0111] deriving thin boards at
laminar thickness (hereafter "sticks") from a feedstock of single
forest or multiple forest derived single and/or multi grade logs,
[0112] drying the sticks at least to some extent, [0113]
(optionally) taking each stick to its finished width by any
suitable means, [0114] assessing each board for appearance and
streaming for endwise joining sticks, endwise joining sticks to at
least the length of the lumber to be engineered, [0115] panel
forming to at least a desired width the endwise joined sticks,
[0116] forming boards of desired width from the panel or panels,
and [0117] laminating boards as aforesaid (optionally with others)
so as to provide an appropriate exterior appearance for the
engineered lumber.
[0118] Preferably the sticks have been cut to a customer length
prior to lamination.
[0119] Preferably better appearance boards are to the outside of
the transverse section of the main faces of the laminated
product.
[0120] Preferably any one or more of the features of the system is
substantially as hereinafter described with reference to any one or
more of the accompanying drawings.
[0121] In another aspect the present invention consists in a method
of producing dimensional lumber reliant upon a breakdown of the
source wood to boards and the subsequent use of such boards with
knowledge of their individual gradings (preferably after drying)
for streaming and/or placement in a laminate structure.
[0122] Preferably breakdown from logs is in a pattern to minimise
spike knots.
[0123] Preferably the total breakdown is or has been to effect, as
far as is practical, a maximising of the spread of properties
amongst laminae ["sticks"].
[0124] The sticks derived from a population of logs and hence the
laminae incorporated into the corresponding population of laminates
would be of uniform thickness with the thickness preferably being
chosen prior to breakdown of the logs. Such thickness preferably
would be not less than 4 mm and not greater than 17 mm.
[0125] The aforesaid range ensures a thickness can be chosen that
is amenable to the production and processing of sticks, while
ensuring an adequate number of sticks can be produced to reveal the
spread of properties and ensure a laminate will comprise at least 3
laminae for an appearance product and preferably at least 4 laminae
for a structural product.
[0126] In practice the chosen thickness would normally be between 6
mm and 11 mm.
[0127] In another aspect the present invention consists in a method
of deriving an elongate laminate product from a tree or logs
thereof, said method comprising or including [0128] (I) deriving
logs of short length and/or of a variety of lengths, [0129] (II)
(optionally) profiling longitudinally at least part of the
periphery of each log, [0130] (III) longitudinally breaking such
log lengths or at least part profiled logs down to boards, such
breakdown to boards at least predominantly deriving surfaces
defined by a longitudinal splitting and/or sawing (although at
least one or some of the surfaces of each or some boards can be
optionally dressed surfaces), [0131] (IV) drying the boards, [0132]
(V) endwise finger jointing at least some of the dried boards
[0133] a. of similar or the same transverse dimensions and [0134]
b. of like characteristics (e.g. selected from some assessment of
at least one of the characteristics selected from the group of
stiffness, strength and appearance) in order to derive boards of
greater length (e.g. to at least customer length), and [0135] (VI)
laminating such boards to derive a laminated elongate product, such
lamination being to provide both or either [0136] (i) a structural
member (e.g. beam, stud, etc.) having greater transverse dimension
or bending resistance, or both, in a plane normal to the plane or
planes of lamination rather than parallel thereto, boards of known
characteristics being substantially optimally positioned in the
laminated section, and/or [0137] (ii) a structural or other member
having its greater transverse dimension parallel to the laminating
plane or planes (and, optionally, having one exposed face of
greater transverse dimension as an appearance face), boards of
known characteristics being substantially optimally positioned in
the laminated section.
[0138] In another aspect the present invention consists in an
elongate engineered timber product having a laminated transverse
substantially rectangular or square cross section transverse to the
longitudinal axis, [0139] wherein the cross section [0140] i. in
one of its major or minor axes is co-extensive with the transverse
width parallel to that same axis of each lamina. and [0141] ii. in
the other of its major or minor axes, has the accumulated
thicknesses of the individual lamina, [0142] and wherein each or
any lamina is over the length of the product either [0143] (I) a
unitary stick from a log, or [0144] (II) an endwise (e.g. finger
jointed, lap jointed, and/or other such jointed) joined structure
of at least two sticks ("stick components") from a log or logs,
[0145] and has the grain of its stick or stick components running
at least substantially longitudinally of said longitudinal axis,
[0146] and wherein there has been a profiling of laminae strength
and/or stiffness characteristics across that transverse axis of
accumulated thickness thereby to engineer a strength and/or
stiffness characteristic of the product in planes normal to such
thicknesses.
[0147] In another aspect the present invention consists in an
elongate engineered timber product having a laminated transverse
substantially rectangular or square cross section transverse to the
longitudinal axis, [0148] wherein the cross section [0149] (a) in
one of its major or minor axes is co-extensive with the transverse
width parallel to that same axis of each lamina. and [0150] (b) in
the other of its major or minor axes, has the accumulated
thicknesses of the individual lamina, [0151] and wherein each or
any lamina is over the length of the product either [0152] (I) a
unitary stick from a log, or [0153] (II) an endwise (e.g. finger
jointed, lap jointed, and/or other such jointed) joined structure
of each at least two sticks ("stick components") matched as to
strength and/or stiffness from a log or logs, [0154] and has the
grain of its stick or stick components running at least
substantially longitudinally of said longitudinal axis, [0155] and
wherein there has been a profiling of laminae strength and/or
stiffness characteristics across that transverse axis of
accumulated thickness thereby to engineer a strength and/or
stiffness characteristic of the product in planes normal to such
thicknesses, such profiling having the effect of at least
emphasising the presence of stronger and/or stiffer sticks to the
outside of the transverse section.
[0156] In another aspect the present invention consists in an
elongate engineered timber product made to length L and having a
laminated transverse substantially rectangular or square cross
section transverse to the longitudinal axis, [0157] wherein the
cross section [0158] (a) in one of its major or minor axes is
co-extensive with the transverse width parallel to that same axis
of each lamina. and [0159] (b) in the other of its major or minor
axes, has the accumulated thicknesses of the individual lamina,
[0160] and wherein at least most laminae over the length L of the
product are an endwise (e.g. finger jointed, lap jointed, and/or
other such jointed) joined structure of sticks derived from a log
resource with the grain of its stick components running at least
substantially longitudinally of said longitudinal axis, [0161] and
wherein there has been a profiling of laminae strength and/or
stiffness characteristics across that transverse axis of
accumulated thickness thereby to engineer a strength and/or
stiffness characteristic of the product in planes normal to such
thicknesses.
[0162] In another aspect the present invention consists in an
elongate engineered timber product made to length L and having a
laminated transverse substantially rectangular or square cross
section transverse to the longitudinal axis, [0163] wherein the
cross section [0164] (a) in one of its major or minor axes is
co-extensive with the transverse width parallel to that same axis
of each lamina and [0165] (b) in the other of its major or minor
axes, has the accumulated thicknesses of the individual lamina,
[0166] and wherein at least a sufficient number of the laminae is
over the length L of the product are an endwise (e.g. finger
jointed, lap jointed, and/or other such jointed) joined structure,
each of longitudinally aligned and matched as to strength and/or
stiffness, sticks derived from log resource(s). [0167] and wherein
there has been a profiling of streamed laminae already endwise
joined of total length of at least L across that transverse axis of
accumulated thickness thereby reliant on stronger and/or stiffer
laminae being placed to the outside to engineer a strength and/or
stiffness characteristic of the product in planes normal to such
thicknesses.
[0168] In another aspect the present invention consists in elongate
engineered timber products, [0169] wherein each product having a
laminated transverse substantially rectangular or square cross
section transverse to its longitudinal axis, [0170] and wherein the
cross section of each product [0171] (a) in one of its major or
minor axes is co-extensive with the transverse width parallel to
that same axis of each lamina and [0172] (b) in the other of its
major or minor axes, has the accumulated thicknesses of the
individual lamina, [0173] and wherein at least some laminae over
the length of each product is an endwise (e.g. finger jointed, lap
jointed, and/or other such jointed) joined structure of sticks,
each such stick being derived from a log, [0174] and wherein using
a sufficient log resource laminae strength and/or stiffness
characteristics have been profiled across that transverse axis of
accumulated thickness thereby to engineer for each product a
strength and/or stiffness characteristic of each of the products in
planes normal to such thicknesses.
[0175] In another aspect the present invention consists in an
elongate engineered timber product of length L having a laminated
transverse substantially rectangular or square cross section
transverse to the longitudinal axis, [0176] wherein the cross
section [0177] (i) in one of its major or minor axes is
co-extensive with the transverse width parallel to that same axis
of each lamina. and [0178] (ii) in the other of its major or minor
axes, has the accumulated thicknesses of the individual lamina,
[0179] and wherein at least some laminae over the length L of the
product is an endwise (e.g. finger jointed, lap jointed, and/or
other such jointed) joined structure of sticks ("stick components")
of length much less than L derived from log resources, [0180] and
wherein there has been a profiling of laminae characteristics
across that transverse axis of accumulated thickness thereby to
best face the outside of the product on the opposed faces not
showing the accumulated thicknesses, [0181] and wherein each said
endwise joined structure has been of at least length L prior to
lamination and with at least some having been to a length greater
than L.
[0182] In respect of any of the foregoing there are the following
preferences and/or options.
[0183] The sticks derived from a population of logs and hence the
laminae incorporated into the corresponding population of laminates
would be of uniform thickness with the thickness preferably being
chosen prior to breakdown of the logs. Such thickness preferably
would be not less than 4 mm and not greater than 17 mm.
[0184] The aforesaid range ensures a thickness can be chosen that
is amenable to the production and processing of sticks, while
ensuring an adequate number of sticks can be produced to reveal the
spread of properties and ensure a laminate will comprise at least 3
laminae for an appearance product and preferably at least 4 laminae
for a structural product.
[0185] In practice the chosen thickness would normally be between 6
mm and 11 mm.
[0186] Preferably the logs are derived from debarked tree stems or
debarked longer log lengths.
[0187] Preferably the logs are at least primarily in the range of
from 0.5 m to 2.4 m in length.
[0188] The logs may include primarily or may include a good
percentage of higher tree stem regions.
[0189] Preferably said profiling is performed so as to assist by
the provision of at least one datum flat and one datum edge to
facilitate breakdown.
[0190] Preferably the optional profiling is to provide at least one
datum flat and edge to facilitate breakdown by either [0191] (i)
splitting by a longitudinal splitting procedure (e.g. as
hereinafter described) or [0192] (ii) a sawn breakdown of the log
lengths to billets and thereafter the further breakdown of at least
some of the billets to boards reliant upon a longitudinal splitting
procedure (e.g.; as hereinafter described).
[0193] Preferably the profiling is such as to provide a contour of
the log periphery which best provides boards or billets reducible
to boards by a splitting process with boards of greater transverse
section symmetrically cut from the log.
[0194] The profiling can include the provision of four flats for
the purpose of subsequent breakdown and, if desired, rebates to
ensure an ensuing splitting process can provide at least primarily
boards of rectangular section and/or square section.
[0195] In some forms at least some initial longitudinal breakdown
by sawing can occur and this may include the profiling steps and/or
some initial billet provision for subsequent further longitudinal
breakdown by preferably a splitting procedure.
[0196] Preferably the splitting procedure involves the still
"green" wood being heated to facilitate splitting, (e.g. by any of
the processes herein described (e.g. bath, steam chamber, or other
non drying heating process)).
[0197] Preferably the characteristics of the boards is determined
wholly or primarily post drying. The determination of the
characteristics of the boards can follow or precede, or both,
trimming of at least one transverse dimension of at least some of
the boards.
[0198] Preferably boards of a suitable appearance may be selected
by inspection and/or scanning as "appearance" boards whilst
preferably boards (whether appearance boards or otherwise) may be
assessed by inspecting and/or scanning and/or grading for strength
and/or stiffness.
[0199] Preferably the endwise finger jointing of at least some of
the dried boards is to provide a feedstock of boards at least as
great as a desired customer length or multiple of desired customer
length (such as 2.4 m in length or greater) even if there may be a
subsequent cutting step at the time of or post or during
lamination.
[0200] Preferably the method just described provides streams of
dimensional appearance and/or structural timber.
[0201] In another aspect the present invention consists in a method
of deriving an elongate laminate product from a tree, said method
comprising or including [0202] scanning tree stems and/or logs
after debarking and deriving log lengths of lower value tree stem
regions that are substantially defect free (preferably from those
regions upwardly of the butt log), [the logs preferably being at
least mainly from 0.5 m to 2.4 m in length] (or 1.2 m to 2.4 m),
[0203] profiling at least in part the exterior of each log, [0204]
longitudinally breaking such at least in part profiled log lengths
down to boards reliant as a datum on at least part of the log
profiling, such breakdown at least predominantly deriving surfaces
of the boards defined predominantly by a longitudinal splitting
and/or sawing, [0205] drying the boards, and [0206] both or either:
[0207] (A) inspecting, scanning and/or grading the boards [before
and/or after, optionally trimming at least one side of some or all
boards to extent required to match boards for transverse section
and/or to customer width], [0208] endwise finger jointing at least
some of the boards of the same or substantially same transverse
dimensions, and optionally substantially same grade, to assemble an
elongated composite board [and, if necessary, prior to or post
[0209] lamination transversely cutting the elongated composite
board in order to derive boards to customer length (preferably
greater than 2.4 m in length)], and laminating such boards in a
process to derive an elongate laminate product of customer length,
such lamination being to provide a structural member (e.g. beam,
stud, etc.) having by appropriate placement of different
characteristics in the laminate a desired structural performance,
[0210] (B) inspecting, scanning and/or grading the boards, [before
and/or after optionally trimming at least one side of some or all
boards to extent required to match boards for transverse section
and/or to customer width], [0211] endwise finger jointing at least
some of the transversely dimensioned boards of the same or
substantially same transverse dimensions, and optionally
substantially same grade, to assemble an elongated composite board
[and, if necessary, prior to or post lamination transversely
cutting the elongate composite board in order to derive boards to
customer length (preferably greater than 2.4 m in length)], and
[0212] laminating such boards in a process to derive an elongate
laminate product of customer length, such lamination being to
provide a structural or other member having its greater transverse
dimension parallel to the laminating plane or planes and having one
exposed face of greater transverse dimension as an appearance
face.
[0213] Preferably the optional profiling is to provide at least one
datum flat and edge to facilitate breakdown by either [0214] (i)
splitting by a longitudinal splitting procedure (e.g. as
hereinafter described) or [0215] (ii) sawing of the log lengths to
billets and thereafter the further breakdown of at least some of
the billets to boards reliant upon a longitudinal splitting
procedure (e.g. as hereinafter described).
[0216] Preferably the profiling is such as to provide a contour of
the log periphery which best provides boards or billets reducible
to boards by a splitting process with boards of greater transverse
section symmetrically cut from the log.
[0217] Preferably the method is performed substantially as
hereinafter described with reference to any one or more of the
accompanying drawings.
[0218] In a further aspect the present invention consists in a
method of value extraction from tree stem timber so as to provide
engineered structural products and/or appearance products, which
when from lower valued material and/or lower valued logs of a tree
stem, will represent lumber value enhancement reliant upon a method
of deriving elongate laminate products by a method of the present
invention.
[0219] In another aspect the invention is an elongate dimensional
structural and/or appearance timber product, the product being a
laminate of at least primarily sliced boards of previously
determined characteristics (i.e. as a board post board creation)
thereby having allowed selective positioning of such boards in the
laminate to allow use of boards of different characteristics yet
still provide the desired (i) structural, (ii) appearance or (iii)
both (i) and (ii) outcome.
[0220] Preferably at least one of the boards has been finger
jointed prior to lamination to provide the required length.
[0221] Preferably each of the boards has had its characteristics
determined post drying, etc.
[0222] Preferably the outcome is (i) or (iii).
[0223] Preferably the separation of characteristics is in a spaced
minor axis sense for structural requirements.
[0224] In another aspect the present invention consists in a method
of producing such a timber product, which method includes at least
[0225] (A) [0226] (I) board creation and grading/assessing, or
[0227] (II) grading/assessing and board creation, [0228] AND (B)
lamination of boards when dry reliant for placement on such
grading/assessment.
[0229] Preferably breakdown from logs is in a pattern to minimise
spike knots.
[0230] Preferably the total breakdown is or has been to effect, as
far as is practical, a maximising of the spread of properties
amongst lamina ["sticks"].
[0231] Preferably the cutting of each stick is or has been from a
minimum number of growth years as is practical.
[0232] In yet a further aspect the present invention consists in a
panel or panels formed by or during performance of a method as
aforesaid.
[0233] In another aspect the invention is a laminate, engineered
structural lumber or engineered appearance lumber made by a method
of the present invention.
[0234] In a further aspect the invention consists in a laminate of
laminae of uniform rectangular cross-sections or depths and lengths
arranged randomly in the laminate, such laminae having been derived
from a feedstock comprising a population of logs (single or
multigrade) wherein the population of laminae comprises all of the
laminae that can be derived from the population of logs (exclusive
only of laminae that are not of acceptable rectangular
cross-section and/or length), and where each cross-section of each
lamina represents a maximum of one twentieth (preferably a maximum
of one thirtieth) of the log cross-section, or the thickness of
each lamina represents a maximum of one fifteenth of the small end
log diameter.
[0235] Preferably at least some of the laminae result from
streaming of endwise joined parts thereof.
[0236] Preferably no substantial pith content is in outside
laminae.
[0237] The sticks derived from a population of logs and hence the
laminae incorporated into the corresponding population of laminates
would be of uniform thickness with the thickness preferably being
chosen prior to breakdown of the logs. Such thickness preferably
would be not less than 4 mm and not greater than 17 mm.
[0238] The aforesaid range ensures a thickness can be chosen that
is amenable to the production and processing of sticks, while
ensuring an adequate number of sticks can be produced to reveal the
spread of properties and ensure a laminate will comprise at least 3
laminae for an appearance product and preferably at least 4 laminae
for a structural product.
[0239] In practice the chosen thickness would normally be between 6
mm and 11 mm.
[0240] In yet a further aspect the invention consists in a laminate
of laminae of uniform rectangular cross-sections or depths and
lengths arranged randomly or otherwise in the laminate, such
laminae having been derived from a feedstock comprising a
population of logs (single or multigrade) wherein the population of
laminae comprises all of the laminae that can be derived from the
population of logs (exclusive only of laminae or material for
laminae that are not of acceptable rectangular cross-section and/or
length), and where each cross-section of each lamina represents a
maximum of one twentieth of the log cross-section, or the thickness
of each lamina represents a maximum of one fifteenth of the small
end log diameter.
[0241] Preferably each lamina represents a maximum of one thirtieth
of the log cross-section.
[0242] Whilst minimising wastage is a significant attribute of the
process of the present invention the primary value arises from
taking advantage of two facts, [0243] 1) that high performance
dimensional lumber products do not need to contain the "performance
defining wood" throughout their bulk (i.e. structural products only
require high strength wood in outer elements of the cross-section,
appearance products only require an appearance grade surface), and
[0244] 2) there is a natural distribution of wood properties within
a log and between logs.
[0245] In order to keep lost fibre to acceptable limits the process
preferably employs slicing and/or fine band saw technology for the
bulk of its breakdown into sections.
[0246] As well because the process contemplates finger jointing or
any acceptable alternative (lap jointing) into a continuous length
before cutting to a customer required length, as an integral part
of the process, short logs ("shorts") can be used or created from
logs with excessive bend or taper. The value of the process is
driven more by its ability to use low value logs than by maximising
yield, however the process is preferably able to keep yields above
acceptable minima.
[0247] The process can add value to any log--including butt logs.
In practice the process targets low value (i.e. low cost) logs only
because it is expected they will produce the highest margin.
[0248] The present invention in its preferred forms is also based
upon the contention that there is sufficient high strength board
extraction derivable from low value upper log forming regions of a
tree, and from shorts provided an effective process of high yield
and not involving any mandatory substantial encroachment into
materials extracted from high value lower most logs of the tree is
available, yet still allowing such encroachment as and when
wanted.
[0249] The present invention in another aspect also recognises a
capability of cutting upper regions, (e.g. optionally beyond those
of the butt log and perhaps or preferably above the second log)
into short lengths [in order to counter the influence of taper,
sweep, curvature, etc.], thereafter machining with minimal sawing
smaller diameter logs than those of a butt log and shorter in
length (e.g. 0.5 m to 2.4 m) into boards, drying such boards,
matching boards after the drying procedure, edge trimming if
required to a required transverse dimension, endwise joining by
finger jointing at least to a customer required length, thereafter
[0250] (a) preparing directly laminated and dimensional structural
timbers or, [0251] (b) after a panel forming procedure, slitting
(e.g. by shearing or fine sawing) from the panel boards of customer
required transverse dimension to allow their subsequent use in
appearance and/or structural laminates.
[0252] The following process options are proposed in order to meet
one or more of the foregoing objects:
A Sectioning
[0253] Sectioning options (method of breaking down the cross
section after cutting the logs to length) are a trade off between
yield and technical risk/process complexity. There are at least two
sectioning options contemplated. The sectioning option is
independent of the targeted output (structural or appearance).
[0254] 1. Sectioning option 1 would be chosen if a machine of the
correct size could be purchased at reasonable cost and the
technical issues surrounding the "slice overhang" was easily dealt
with. [0255] 2. Sectioning option 2 can be used with existing
equipment and has very low technical risk. B Outputs
[0256] The process can produce three outputs by employing three
process scenarios. [0257] 1. ALL-IN. If the process simply slices
the logs into, say, approximately 10 mm width increments (maximum
width of up to log small end diameter--SED), at about 6.5 mm thick,
dry the resultant boards, edge dress and finger joint like width
boards into customer required length (approximately 20 different
widths), and edge joint these into a panel; this panel can be slit
into widths which coincide with the customer required lumber width
and laminate these re-slit boards into the customer required
thickness. This process will produce an "all in" product. By
accident some of the slit boards may grade as appearance and these
could be put to the outside of any laminated board. This process
could produce a large panel substrate for addition of finishing
veneers. The structural sections produced would be some improvement
on sawn timber strength because of the random positioning of
defects in a six layer major axis laminate and the statistical
reduction in the range and hence number of products in a given
sample falling below the minimum required strength. This may be the
preferred process if the output had a high proportion of No 1
framing or better even using low value input, and if a significant
market does not exist for superior product. NOTES: The 10 mm width
increments lead to a large number of board widths to deal with but
higher yields for either sectioning option. A 20 mm width increment
would halve the number of board width lines for a small decrease in
yields. The process may well be edge jointing boards only to
re-slit these into dimensions not much different from the original
board width. [0258] 2. APPEARANCE. If the process were to target a
large proportion of appearance grade products it could follow the
same process except that it would grade each board into, say, about
3 grades before finger jointing. This would necessitate 3 times
more finger jointing streams and three edge jointing streams but
would result in a far higher yield of appearance grade output,
(more than three times greater). The resultant slit down panels
(i.e. those produced by edge gluing) would be laminated with the
best grade on one side the second best on the other side and the
lowest grade in the middle. (Assuming 19 mm thickness for
appearance products). [0259] 3. STRUCTURAL. If the process were to
target predominantly structural outputs then it would slice into
width increments of 46 mm (or other common finished thickness). The
process would slit each of the boards after drying and during edge
dressing into the 46 mm width (or other green pre-dressed customer
width) and grade into at least 2 grades for finger jointing. The
panel production and re-slitting step would be eliminated. The
finger jointed boards would be laminated about the minor axis up to
the customer required section width. NOTES. If there is a high
incidence of full width defects which cause the 46.times.6.5 mm
sections to break during the process then the process will need to
consider the cost of rework versus an option to grade at sliced
width, finger joint and laminate to a double laminate before
slitting to customer required thickness and re-grading.
[0260] As well as these three options a mix and match scenario
incorporating the appropriate features of each of these options may
be appropriate for producing a mixed output.
Preferred Actual Process Steps
[0261] 1. Logs will be debarked in the usual manner. [0262] 2.
These logs will be cut to the process length range. [0263] The
process length will be between some maximum (L max) and some
minimum (L min) but subject to the following rules. [0264] L min is
half L max thus any straight log greater than L min can be entirely
processed. [0265] Logs with excessive bend or taper would be cut
into sections which maximised the yield by tending to cut shorter
than L max would allow and/or perhaps even discarding a short
piece. [0266] All saw cuts will avoid the "Whorls" such that the
process will not need to finger joint through any knots. [0267] 3.
EITHER: the log will have four "flats" cut in 20 mm across the
flats increments, streamed, profiled, heated and sliced. Profiling
may be carried out prior to each slice in a continuous profiling
slicing operation or the profiling may be entirely completed before
slicing. (or some process in between) [0268] 4. OR: The logs will
be sawn into rectangular sections in the appropriate dimension
increment. Rectangular sections of like dimensions will be
streamed. These rectangular sections may require some dressing.
These rectangular sections will be heated and sliced. [0269] 5. The
sliced boards may be restrained and dried in such a manner to
retain straightness and minimise shakes (internal splits) or dried
unrestrained. This could be by conventional batch methods or a
continuous method that takes advantage of the prospect of being
able to rapidly dry thin sections. Also, the thin sections mean the
process can consider infra red or micro wave as well as normal
hot-air convection methods. [0270] 6. Optionally: Grade for
appearance characteristics and separate into "like property"
streams accordingly. [0271] 7. Edge dress the boards to account for
differential shrinkage. [0272] 8. Optionally: Slit to required
width (Customer required width or thickness). [0273] 9. Optionally:
Grade for strength and separate into "like property" streams
accordingly. [0274] 10. Finger joint boards of like width and/or
like grade into a multiple of customer required length. [0275] 11.
Optionally: Edge joint the resultant boards into a continuous panel
either random or by grade and re-slit this panel into the customer
required dimension. (Width or thickness). The process may wish to
produce wide panels. The process may wish to laminate two panels
before further slitting to avoid unstable narrow laminates. [0276]
12. Optionally: Grade the slit boards by appearance or strength
properties. [0277] 13. Laminate these boards (laminae) into the
customer required dimensions and properties, randomly OR by
selected layers of appearance graded boards (lamina) OR by selected
layers of strength graded boards (laminae).
[0278] Preferred forms of the present invention will be described
hereinafter with reference to two preferred streamings occurring
downstream of a drying procedure.
[0279] Irrespective however of the streaming preferably endwise
finger jointing occurs post a drying stage.
[0280] Whilst reference is made to post drying characteristic
assessment/grading in some forms where less dry or green boards can
correlate in characteristics to the dry or more dry boards such
assessment/grading can occur earlier in the process but only post
board creation.
BRIEF DESCRIPTION OF DRAWINGS
[0281] Preferred forms of the present invention will now be
described with reference to the accompanying drawings in which,
[0282] FIG. 1 shows a flow diagram of one process in accordance
with the present invention having the capability of streaming
components after the drying and inspection steps and preferably
prior to finger jointing of individual boards, one stream being to
produce laminates to act as beams, studs or the like reliant upon
lamination planes normal to the greatest dimension of the board,
e.g. forms such as those that by choice of appropriate materials,
web space, stronger timber boards, and those which preferably have
at least one appearance face where the lamination is parallel to
the greater transverse dimension of each board and said at least
one appearance face,
[0283] FIG. 2A shows a first option for breakdown of logs of
similar dimension where any machining other than splitting and
profiling is kept to a minimum (it being appreciated that rebates
can be machined in by cutting, milling, routing or the like to
allow better location relative to splitting apparatus),
[0284] FIG. 2B shows by a mixture of heavy lines and less heavy
lines respectively saw cuts and splitting during a breakdown,
[0285] FIG. 3A shows a wooden billet such as that provided
centrally of the breakdown option of FIG. 2B showing wooden billet
location relative to a locating side bar to oppose side forces from
the acute angle slicing geometry,
[0286] FIG. 3B shows the section of AA of FIG. 3B,
[0287] FIG. 3C shows the end elevation BB,
[0288] FIGS. 4A and 4B shows side elevation and end view
respectively of a slicing pattern for a short logs to minimise
drying deformation by cutting boards symmetrically about the log
centre line,
[0289] FIG. 4C shows in side elevation and FIG. 4D an end view
showing how progressive slicing can provide boards of the required
timber thickness,
[0290] FIG. 5 shows a plan view of one arrangement whereby after
pre-heating the logs can be introduced to a profiling and slicing
process that may include the slicing machine and profiling machine
in series, such apparatus being appropriate for the option shown by
reference to FIG. 2A,
[0291] FIG. 6 shows apparatus from above adapted after heating the
logs to provide a standard slicing process, such slicing process
following a breakdown of the logs as detailed in FIG. 2B,
[0292] FIG. 7A is a similar view to that of FIG. 2B but showing how
the heavy line saw cuts can provide a number of rectangular
sections or square sections perhaps of a multiple of 46 mm (or any
green pre-dressed finished dimension required by the customer) with
the larger sections concentric with the log centre,
[0293] FIG. 7B showing sections with at least one side of a
relatively large dimension which can be sent to wide slicer and
FIG. 7C showing a number of square or rectangular sections of a
small which can be sent to a smaller slicer,
[0294] FIG. 8 shows how the sliced boards can be prepared for
drying whilst being restrained to ensure the dry boards exit the
dryer more or less straight, the typical process being to stack in
several batches of like length and weight before charging to a
batch dryer, but other drying process and/or a continuous drying
process can be used,
[0295] FIG. 9 shows an optional visual or camera scan for
appearance critical features and streaming according to these
features,
[0296] FIG. 10 shows the edge dressing or optional (for structural)
combined edge dressing and slitting (by guillotining or fine
sawing) operation,
[0297] FIG. 11 shows an optional density test or stiffness test for
structural properties and streaming according to these
features,
[0298] FIG. 12 shows a finger jointing process,
[0299] FIG. 13A is an end view of a panel formed by edge gluing of
panels post finger jointing whilst FIG. 13B is a partial plan view
of such a panel as shown in FIG. 13A showing the finger joints
spaced along the length, such a panel being adapted for slitting
parallel to the edge joints to a desired customer board width prior
to lamination,
[0300] FIG. 13C shows such a panel slitting to provide constant
width boards from a panel as shown in FIG. 13A and FIG. 13D with
the broken lines parallel to the edge joints shows the lines of
guillotining into constant width boards,
[0301] FIGS. 14A and 14B showing how boards produced from the
guillotine cutting as described with respect to FIG. 13D can be
face to face glue laminated to provide a product preferably but not
necessarily with one at least appearance face on a face that is
parallel to the lamination plane and which is a face of greater
transverse dimension,
[0302] FIG. 15 shows another lamination option [not usually
requiring panel formation as described with reference to FIGS. 13A
through 13D nor the consequent slitting provided they are provided
more or less to the desired width of board by the breakdown system
albeit they may require some edge dressing to customer width], such
boards being laminated with lamination planes normal to the planes
of greater board transverse dimension,
[0303] FIG. 16 shows how for a laminate as shown in FIG. 15 each
board shown is positioned so as to maximise greater strength away
from the centre of the laminate, thereby, by following the
principles of an "I" beam, using lesser strength boards as web
spacers for the higher strength boards thereby better to resist
deflection of the beam in a plane normal to the lamination
planes,
[0304] FIG. 17 shows how for the arrangement as shown in FIG. 14A
there is preferably a high grade layer on one side, a lower grade
layer centrally and a medium grade layer on the reverse face,
[0305] FIG. 18 shows by relationship to a tapering tree stem how
gross value by a process of the present invention can deviate from
the structural and appearance lines of a conventional saw mill, the
line marked "C" being that of conventional sawing and the line
marked "I" being that of the invention,
[0306] FIGS. 19A to 19C show a process from beginning to end in
accordance with preferred options of the present invention, there
being shown an optional departure from the manufacture of purely
structural engineered timber where, as might be in demand from time
to time, appearance engineered timber is required,
[0307] FIGS. 19A to 19C nevertheless show how in the preferred form
of the present invention with a view to enhancing efficiencies the
feedstock is of single forest or multiple forest derived single
and/or multi grade logs,
[0308] FIG. 20 graphically shows representative MOE distributions
of "clear sawn lumber" verses "thin boards inclusive of defects"
from low grade logs (as published by NZFRI and our testing
respectively), along with an inserted table of expected structural
grade outputs of sawn lumber from similar logs (published by
NZFRI).
[0309] FIG. 21 shows the cumulative distribution of MOE for the
thin boards from FIG. 20,
[0310] FIG. 22 shows how multiple sticks or thin boards formed and
end jointed in accordance with the present invention can be
profiled within a laminate, the darker shade boards being those of
greater strength and/or stiffness (i.e. MOE) and those of lighter
shade being those of less strength and/or stiffness (i.e. MOE),
[0311] FIG. 23 shows the expected MOE distribution in our final
assembled product e.g. as in FIG. 22, and
[0312] FIG. 24 is an overlay of FIG. 23 and FIG. 20 clearly showing
expected increase in MOE (e.g. as an indicator of stiffness or
strength or both).
[0313] In the forming of elongate products from tree stems waste
arises in a number of ways.
[0314] One is the waste that is always inherent with the cutting
width of a sawmill saw (the kerf) which wastes material as sawdust
when used as the sole means of longitudinally breaking down logs or
a tree stem. Another area of wastage is the general convergence or
taper of a tree stem thus leading to waste where flitches or boards
of constant breadth and constant thicknesses are to be formed.
Still other wastage arises from the to be expected sweep, crook,
bow, cup, twist and other distortions of tree stems and/or logs
(particularly lower value higher logs) cut therefrom.
[0315] Another area of wastage is a lack of value recovery from
upper logs owing to the lower value properties being traditionally
ascribed to upper logs of a tree stem, to the dimensions and to
wood defects thereof.
[0316] Various methods have been proposed in order to save as much
as possible the wood of a felled tree stem so that unnecessary
amounts of the tree stem are not diverted to chipping or waste. See
for example log reconstruction as disclosed in EP 0013965.
[0317] Longitudinal cutting from log-like structures with a reduced
use or no use of saw blades is known. See for example a kerfless
splitting procedure such as disclosed in New Zealand Patent 231933,
New Zealand Patent 241289, U.S. Pat. No. 4,337,809 and/or U.S. Pat.
No. 5,500,070. See also flitches or planks such as those disclosed
in, for example, New Zealand Patent 502160 (PCT/US98/11566
published as WO 98/56549), U.S. Pat. No. 781,376, U.S. Pat. No.
4,086,944 and U.S. Pat. No. 4,111,247. One method that has been
proposed with a view to saving materials is that disclosed in U.S.
Pat. No. 5,500,070 the full content of which is herein included by
way of reference. This teaches knife cutting of square timber into
thin boards, drying and then their use in multilayer laminated
panels.
[0318] The present invention makes use of some of the
aforementioned technologies including the knife cutting procedures
typified by Linck in some of their aforementioned patent
specifications. The present invention however recognising, as an
example only, the situation of the New Zealand Timber Industry and
taking account of the value proposition whilst keeping yields (i.e.
by reducing waste) within acceptable limits has been prompted by
the situation as follows;
Situation:
[0319] The New Zealand Forest Industry faces greater than a 50%
increase in annual harvested volumes of Radiata Pine over the next
10 years. The bulk of the incremental volume must be exported.
[0320] Log markets for these volumes simply do exist at returns
that will provide forest owners even risk free returns. [0321] The
single greatest volume market for lumber is structural components,
studs, beams, etc. [0322] Radiata Pine will require processing to
meet structural export market requirements for size, stability and
strength. [0323] The larger structural sizes provide
disproportional greater returns per cube, but it is these that are
the most difficult to extract from smaller fast grown trees while
maintaining superior performance characteristics and high
recoveries of the whole log. The longer the product, the more
difficult to maintain specification. [0324] The trees and thus logs
will always be of random lengths about the targeted harvester
length and varying diameters. The market will always require
specific lengths and dimensions for which they will pay a premium.
[0325] Traditional saw milling and processing techniques can not
economically process the whole tree, but prefer the larger and more
expensive specified length butt logs as feedstock. Recoveries ex
the mill, even before remanufacture typically run at only
45.about.55%, with output lengths still random. [0326] Resolving an
economic solution to this disparity between feedstock and market
represents the opportunity. Design Objectives for Preferred
Embodiments of Invention: [0327] Accept any length and diameter of
log. Short random lengths will always be the lowest cost feedstock.
These primarily arise from the top of the tree, and have little
economic value. [0328] Produce any sized structural product that
the customer may order in any length. [0329] Produce only to order,
not to stock, with no other product sizes arising from the process.
[0330] Produce an absolute minimum of waste. [0331] Minimise glue
usage as a significant cost component. [0332] Ensure the end
product has an overall attractive consumer appearance. [0333]
Ensure the product meets structural market specifications. [0334]
Make the process as continuous and automated as possible. [0335]
Minimise the use of capital and operating costs.
[0336] The procedure of the present invention (in preferred
embodiments) by emphasis upon board formation (e.g. from short
length defect reducing still green or substantially green logs from
the lower value upper regions of the tree stem), the subsequent
drying thereof and inspection (preferably thereafter) can minimise
wastage by ensuring direction (e.g. by machine grading and/or
visual inspection) of appropriate materials to appropriate feed
streams for ensuring use as components where required in
dimensional structural or appearance timber laminate
assemblies.
[0337] A preferred process for making customer dimensioned
structural laminate materials and customer dimensions appearance
faced materials (structural or otherwise) preferably involves the
following steps: [0338] 1) harvesting of the trees [0339] 2)
breakdown to logs [0340] 3) optionally streaming of logs [0341] 4)
debarking of logs [0342] 5) optional streaming of debarked logs
[0343] 6) transverse cutting of logs where necessary to improve the
defect free characteristic of the log with respect to knots,
curvature, taper, sweep, etc. [0344] 7) profiling of the logs to be
used in the process [0345] 8) breakdown of the logs into boards,
[0346] 9) drying of the boards, [0347] 10) optional grading of the
boards [0348] 11) trimming at least one transverse dimension of the
boards, [0349] 12) optional grading of the boards, [0350] 13) and
then for streaming into appearance laminates or structural
laminates [0351] 14) finger jointing boards of like transverse
dimension and characteristics, and [0352] 15) optional edge
jointing into a panel and re-slitting to width [0353] 16) optional
grading of boards [0354] 17) optimising use of such boards in a
lamination procedure to provide the desired [0355] outcome, such
lamination using dry timber adhesives post trimming to [0356]
customer length of the components of the lamination
[0357] Preferably for the purpose of finger jointing any suitable
conventional dry timber adhesive system can be used.
[0358] Adhesives for end joining and/or finger joining include any
waterproof glues or others used in any of the prior art laminate
structures herein discussed. A particularly preferred adhesive is a
resorcinol based adhesive as currently used in LVL type
products.
[0359] Table 1 shows typical yields from conventional saw milling.
TABLE-US-00001 TABLE 1 Typical Yield Conventional Saw Mill No 1 No
2 Box Engineering Framing Framing Grade Bds Log type Proportion of
output by grade Butt 7% 38% 25% 25% 5% No 2 Log 4% 21% 32% 37% 6%
No 3 Log 1% 16% 34% 43% 6% No 4 Log 0% 4% 21% 58% 17%
[0360] The present invention provides a significant advantage in
value extraction where in Table 2 hereafter stated are the yields
from the processes, option 1 being an almost exclusive splitting
breakdown of logs as detailed in FIG. 2A whilst option 2 is the
hybrid breakdown system (sawing and splitting) detailed by
reference to FIG. 2B. TABLE-US-00002 TABLE 2 TARGETED YIELDS (Based
on SED projected volumes) Option 1 Option 2 Diameter Minor axis
Major axis Minor axis Major axis OR appearance structural
appearance structural Process laminates laminates laminates
laminates Ex 200 95% 95% 70% 70% Slicer 300 96% 96% 75% 75% 400 97%
97% 78% 78% 500 97% 97% 80% 80% 600 97% 97% 81% 81% Loss on Drying
6.5% 6.5% 6.5% 6.5% input Edge 1.5% 1.5% 1.5% 1.5% clean up Finger
0.3% 0.3% 0.3% 0.3% jointing Panel 0.8% 2.2% 0.8% 2.2% slicing
Discards 0% 10% 3% 13% (Est.) Total 200 86% 76% 62% 54% finished
300 88% 78% 66% 58% 400 88% 78% 69% 61% 500 88% 78% 71% 63% 600 89%
79% 72% 63%
[0361] With such acceptable level yields particularly those of
option 1 since a value enhanced product is also being provided
there is a great prospect of value enhancement of harvested
materials particularly when it can be seen that lesser quality
feedstock materials can be utilised almost completely. Even option
2 provides more than acceptable yields and whilst providing the
same enhanced value products can provide advantages of the kind
shown by FIG. 15.
[0362] A preferred process according to the present invention, at
least for structural lumber, however opts away from panel forming
as a precursor to final stick or thin board width determination.
Instead it opts for structural timber for taking the sticks to the
final customer wanted width and thereafter laminating with
appropriate strength and/or stiffness characteristics throughout
the structure reliant upon the principles previously stated.
[0363] FIG. 1 shows a flow diagram of one process in accordance
with the present invention having the capability of streaming
components after the drying and inspection steps and preferably
prior to finger jointing of individual boards, one stream being to
produce laminates to act as beams, studs or the like reliant upon
lamination planes normal to the greatest dimension of the board,
e.g. forms such as those that by choice of appropriate materials,
web space, stronger timber boards, and those which preferably have
at least one appearance face where the lamination is parallel to
the greater transverse dimension of each board and said at least
one appearance face.
[0364] Breakdown is preferably but not necessarily as follows:
[0365] band sawing for primary breakdown [0366] band and/or
circular sawing for secondary breakdown [0367] a slicing or fine
finish sawing for final breakdown to laminar thickness ("tertiary
breakdown").
[0368] Cutting to length whether lamina or laminate is by sawing
(e.g. circular sawing).
[0369] FIGS. 2 (i.e. 2A, 2B) and 4 (i.e. 4A, 4B) show preferred
patterns of both primary, secondary and tertiary breakdown. These
have the effects of (i) avoiding as far as is practicable spike
knots, and (ii) minimising the number of growth rings in each stick
or board thereby (a) minimising the range of properties within a
single stick and (b) maximising the range of properties amongst
sticks.
[0370] FIG. 2A shows a first option for breakdown of logs of
similar dimension where any machining other than splitting and
profiling is kept to a minimum (it being appreciated that rebates
can be machined in by cutting, milling, routing or the like to
allow better location relative to splitting apparatus).
[0371] FIG. 2B shows by a mixture of heavy lines and less heavy
lines respectively saw cuts and splitting during a breakdown.
[0372] FIG. 3A shows a wooden billet such as that provided
centrally of the breakdown option of FIG. 2B showing wooden billet
location relative to a locating side bar to oppose side forces from
the acute angle slicing geometry.
[0373] FIGS. 4A and 4B shows side elevation and end view
respectively of a slicing pattern for a short logs to minimise
drying deformation by cutting boards symmetrically about the log
centre line.
[0374] FIG. 4C shows in side elevation and FIG. 4D an end view
showing how progressive slicing can provide boards of the required
timber thickness.
[0375] FIG. 5 shows a plan view of one arrangement whereby after
pre-heating the logs can be introduced to a profiling and slicing
process that may include the slicing machine and profiling machine
in series, such apparatus being appropriate for the option shown by
reference to FIG. 2A.
[0376] FIG. 6 shows apparatus from above adapted after heating the
logs to provide a standard slicing process, such slicing process
following a breakdown of the logs as detailed in FIG. 2B.
[0377] FIG. 7A is a similar view to that of FIG. 2B but showing how
the heavy line saw cuts can provide a number of rectangular
sections or square sections perhaps of a multiple of 46 mm (or any
green pre-dressed finished dimension required by the customer) with
the larger sections concentric with the log centre.
[0378] FIG. 7B showing sections with at least one side of a
relatively large dimension which can be sent to wide slicer and
FIG. 7C showing a number of square or rectangular sections of a
small which can be sent to a smaller slicer.
[0379] FIG. 8 shows how the sliced boards can be prepared for
drying whilst being restrained to ensure the dry boards exit the
dryer more or less straight, the typical process being to stack in
several batches of like length and weight before charging to a
batch dryer, but other drying process and/or a continuous drying
process can be used.
[0380] FIG. 9 shows an optional visual or camera scan for
appearance critical features and streaming according to these
features.
[0381] FIG. 10 shows the edge dressing or optional (for structural)
combined edge dressing and slitting (by guillotining or fine
sawing) operation.
[0382] FIG. 11 shows an optional density test or stiffness test for
structural properties and streaming according to these
features.
[0383] FIG. 12 shows a finger jointing process.
[0384] FIG. 13A is an end view of a panel formed by edge gluing of
panels post finger jointing whilst FIG. 13B is a partial plan view
of such a panel as shown in FIG. 13A showing the finger joints
spaced along the length, such a panel being adapted for slitting
parallel to the edge joints to a desired customer board width prior
to lamination.
[0385] FIG. 13C shows such a panel slitting to provide constant
width boards from a panel as shown in FIG. 13A and FIG. 13D with
the broken lines parallel to the edge joints shows the lines of
guillotining into constant width boards.
[0386] FIGS. 14A and 14B showing how boards produced from the
guillotine cutting as described with respect to FIG. 13D can be
face to face glue laminated to provide a product preferably but not
necessarily with one at least appearance face on a face that is
parallel to the lamination plane and which is a face of greater
transverse dimension.
[0387] FIG. 15 shows another lamination option [not usually
requiring panel formation as described with reference to FIGS. 13A
through 13D nor the consequent slitting provided they are provided
more or less to the desired width of board by the breakdown system
albeit they may require some edge dressing to customer width], such
boards being laminated with lamination planes normal to the planes
of greater board transverse dimension.
[0388] FIG. 16 shows how for a laminate as shown in FIG. 15 each
board shown is positioned so as to maximise greater strength away
from the centre of the laminate, thereby, by following the
principles of an "I" beam, using lesser strength boards as web
spacers for the higher strength boards thereby better to resist
deflection of the beam in a plane normal to the lamination
planes.
[0389] FIG. 17 shows how for the arrangement as shown in FIG. 14A
there is preferably a high grade layer on one side, a lower grade
layer centrally and a medium grade layer on the reverse face.
[0390] FIG. 18 shows by relationship to a tapering tree stem how
gross value by a process of the present invention can deviate from
the structural and appearance lines of a conventional saw mill, the
line marked "C" being that of conventional sawing and the line
marked "I" being that of the invention.
[0391] It can be seen from FIG. 19A (the full textual content of
which is incorporated herein) that a run of forest single grade
logs, a run of forest multiple grade logs, multiple forest single
grade logs and/or multiple forest multi grade logs can be used even
if of a short length or deliberately so cut.
[0392] Through a variety of different break down procedures,
preferably all to minimise wastage or unnecessary wastage having
regard to the procedures being performed, thin boards at laminar
thickness can be produced for drying by any appropriate means such
as those disclosed in FIG. 19B, whereupon by a variety of different
procedures, each board of a desired width can be streamed as to
strength and/or stiffness or other structural properties prior to
end-joining by any suitable procedure e.g. butt, scarf, finger, etc
whereupon thereafter, if desired, and preferably prior to
lamination, they are cut to a customer length. Thereafter
lamination by any suitable profiling procedure is adopted
optionally with other machine intervention. FIG. 19C deals with
certain options in that respect.
[0393] Also shown in FIGS. 19B and C is an option for mixed mode
plants scanning for appearance properties with appropriate edge
dressing to production width prior to end-joining with like boards.
Thereafter if desired the panel forming by edge joining and cutting
to various production widths can follow thereby allowing formation
by lamination to a desired appearance product form.
[0394] FIG. 20 graphically shows representative MOE distributions
of "clear sawn lumber" verses "thin boards inclusive of defects"
from low grade logs (as published by NZFRI and our testing
respectively), along with an inserted table of expected structural
grade outputs of sawn lumber from similar logs (published by
NZFRI).
[0395] FIG. 21 shows the cumulative distribution of MOE for thin
boards,
[0396] FIG. 22 shows how by way of example how multiple sticks or
thin boards formed and end jointed in accordance with the present
invention can be profiled with the darker shade boards being those
of greater strength and/or stiffness and those of lighter shade
being those of less strength and/or stiffness.
[0397] FIG. 23 shows the expected MOE distribution in our final
assembled product e.g. as in FIG. 22.
[0398] FIG. 24 is an overlay of FIG. 23 and FIG. 20 clearly showing
expected increase in MOE (e.g. as an indicator of stiffness or
strength or both).
* * * * *
References