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| Home > Tech Info > Plywood Standard And Grade > HPVA standard Grade |
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| · HPVA standard Grade |
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Hardwood Plywood and Veneer Association
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HPVA Grading For Hardwood Plywood:
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Characteristics
vary according to species, but there is a basic grading structure which is
followed for all species described in the current Voluntary Standard. The
most uniform color and grain is at the top of the scale for face grade.
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Grade
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Sub Grade
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Applications & Descriptions
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Face
Grade
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AA
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The
best quality face grade for high end uses such as architectural paneling,
doors and cabinets, case goods, and quality furniture.
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A
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Where
AA is not required but excellent appearance is very important as in cabinets
and furniture.
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B
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Where
the natural characteristics and appearance of the species are desirable.
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C,D,
and E
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Provide
sound surfaces but allow unlimited color variation; grades C, D, and E,
respectively, allow repairs in increasing size ranges. Applications: where
surface will be hidden or a more natural appearance is desired.
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Specialty
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Appearance
characteristics are not standardized and are subject to agreement between the
individual buyer and seller, as in factory finished wall paneling. Usually,
effects such as those created by wormy chestnut, bird’s eye maple, and
English brown oak are considered specialty grade.
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Back
Grade
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1,2,3,and
4
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Back
grades are designed by numbers: 1,2,3, and 4. Requirements of grade 1 are
most restrictive, with grade 2, 3, and 4 being progressively less
restrictive. Grade 1 and 2 provide sound surfaces with all openings in the
veneer repaired except for vertical worm holes not larger than
1.6mm
(1/
16’
᾿.
Grades 3 and 4 permit some open defects; however, grade 3 can be obtained
with repaired splits, joints, bark pockets, laps, and knotholes to achieve a
sound surface if specified by the buyer. Grade 4 permits knotholes up to
102mm
(
4’
᾿ ,in diameter and open splits and joints
limited by width and length.
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Veneer
Inner Ply Grade
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J ,
K , L, and M
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Four
inner ply grades are described with the following letter designations: J,K L,
and M. Grade J is the most restrictive, allowing minimal size openings.
Grades K, L, and M are progressively less restrictive. The least restrictive
grade (M) is usually reserved for piles not adjacent to faces and allows
round and similar shaped openings not to exceed
63.5mm
(2 1/
2’
᾿ and elongated openings up to
25.4mm
(
1’
᾿ as visible on the edges or ends of panels.
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Following are the
accepted face grades as established by the HPVA.
GRADE AA -The veneer shall be
smooth, tight cut and full length. When the face consists of more than one
veneer component or piece, the edges shall appear parallel and be edge matched
as described for the various species in 200-S-9. Rotary cut faces may be whole
piece or multipiece with edge joints tight and no sharp color contrasts at the
joints. Species specified for natural color will allow color contrasts, but
must be book matched or conform to the type of matching specified. The
components of plain sliced (flat cut) faces will be book matched, unless
otherwise specified, and arranged, at the option of the woodworker, with a
running, balanced, or center match, unless otherwise specified. Plain sliced
faces will consist of two or more components and rotary faces will consist of
one or more components with no component less than
152 mm
(6") wide except for outside components
which may be less than
152 mm
(6") to allow for certain types matching or panel edge trim loss. No plain
sliced components will have a split heart. No full quarter cut is allowed in
plain sliced faces. The width of any single component in quartercut rift cut or
comb grain faces shall not be less than
76 mm
(3") except for outside components which
may be less than
76 mm
(3") to allow for matching and edge trimming.
Hardwood veneer faces from species not covered in 200-S-9
may contain small burls and occasional pin knots not to exceed
6 mm
(1/4") in total diameter and
3 mm
(1/8") in diameter of the dark pin
knot centers. Color streaks or spots: two repaired, tapering hairline splits
not to exceed
1.5 mm
(1/16") by
152 mm
(6"); and small inconspicuous repairs are also permitted. Unfilled
wormholes. rough cut veneer. knots (other than pin knots), shake, and doze and
other forms of decay will not be permitted.
GRADE A - The veneer shall
be smooth. tight cut and full length. When the face consists of more than one
veneer component or piece, the edges shall appear parrel and be edge matched as
described for the various species in 200-S-9. Rotary cut faces may be whole
piece or multipiece with tight edgejoints; however, no sharp colorcontrasts are
permitted at the joints and the face will provide a good general appearance.
Species specified for natural color will allow color contrasts, but must be
book matched or conform to the type of matching specified. The components of
plain sliced (flat cut) faces will be book matched, unless otherwise specified,
and arranged, at the option of the woodworker, with a running, balanced, or
center match, unless otherwise specified. Plain sliced faces will consist of
two or more components and rotary faces will consist of one or more components,
with no component less than
127 mm
(5") wide except for outside components which may be less than
127 mm
(5") to allow for certain types
matching or panel edge trim loss. Split heart is permitted if manufactured cathedral
is achieved. No full quarter cut is allowed in plain sliced faces. The width of
any single component in quarter cut, rift cut or comb grain faces shall not be
less than
76 mm
(3") except for outside components which mav be less than
76 mm
(3") to allow for matching and
edge trimming. In some species sapwood is permitted: in other species it may be
permitted bv agreement between buyer and seller.
Hardwood veneer faces from species not covered in 200-S-9
may contain small burls and occasional pin knots not to exceed
6 mm
(1/4") in total diameter and
3 mm
(1/8") in diameter of the dark pin
knot centers. Color streaks or spots, two repaired, tapering hairline splits
not to exceed
1.5 mm
(1/16") by
152 mm
(6"); and small inconspicuous repairs are also permitted. Unfilled
wormholes. rough cut veneer, knots (other than pin knots), shake, and doze and
other forms of decay will not be permitted.
GRADE B - The veneer shall
be smooth, tight cut and full length. Slip or book matched veneers are
available if specified bv the buver. If not specified. multipiece faces will be
pleasingly matched. Sharp color contrasts at the joints are not permitted. and
natural variations in grain and color will be blended to the extent possible.
Species specified for natural color will allow color contrasts, but must be
pleasing matched or conform to the type of matching specified. Plain sliced
faces will consist of two or more components with no component less than
76 mm
(3") wide and rotary faces will
consist of one or more components with no component less than
102 mm
(4"). Outside components may be
less than
76 mm
(3") for plain sliced faces and
102 mm
(4") for rotary faces to allow for certain
types of matching or panel edge trim loss. Some full quartercut is permitted in
plain sliced faces. For some species unlimited sapwood is allowed, and in other
species a percentage of sapwood is allowed.
Hardwood veneer faces from species not covered in Section
2OO may contain small burls and occasional pin knots not to exceed
6 mm
(1/4") in total diameter and
3 mm
(1/8") in diameter of the dark pin
knot centers. Color streaks or spots, two repaired, tapering hairline splits
not to exceed
3 mm
(1/8") by
203 mm
(8"); and small inconspicuous repairs are also permitted. Unfilled
wormholes, rough cut veneer, knots (other than pin knots), shake, and doze and
other forms of decay will not be permitted. |
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