hardwood lumber. cross section of a tree grading hardwoods hardwood lumber is graded on the basis of...
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HARDWOOD LUMBER
CROSS SECTION OF A TREE
HEA
RTW
OO
DS
AP
WO
OD
ME
DUL
AR
Y R
AY
S
CA
MB
IUM
OUT
ER
& IN
NER
BA
RK
EA R LY WOO D
LATEWOO D
PIT
H
GRADING HARDWOODS
Hardwood lumber is graded on the basis of the size and # of cuttings which can be obtained from a board.
What things might limit the number and size of cuttings?
Splits Knots Bark Rot
GRADING HARDWOODS
Better grades yield larger proportions of the board in a few large cuttings
Lower grades yield smaller proportions of the board in a large number of small cuttings
How Lumber Is Sold
Rough S2S (Surfaced two sides) S4S (Surfaced four sides)
Rough lumber starts at 1” thickLumber thickness is expressed in
quarters
Lumber Expressed in Quarters
Thickness
Rough Surfaced AWI
1” 4/4 13/16” 3/4”
1 1/4” 5/4 1 1/16” 1”
11/2” 6/4 1 5/16” 1 1/4”
1 3/4” 7/4 1 1/2” 1 3/8”
2” 8/4 1 3/4” 1 1/2”
Physical Characteristics Of Wood
Sapwood – The light colored living wood near the outside of the tree
Heartwood – The central part of the tree
*An unlimited amount of each allowed in the clear face
Stains – Allowed if removable by surfacing
Mineral Streaks – Allowed in the clear face
Physical Characteristics Of Wood
Sticker Stain – Not permitted Season Checks – Checks in
wood not deep enough to be visible in the finished product
Burl – A swirl or twist in grain usually near a knot. Allowable as long as it has a sound center
Physical Characteristics of Wood
Warp – Any variation of the true plane of the board Types of warps
Bow Crook Cup Twist Kink The Dreaded Combo
Physical Characteristics of Wood
Boards must be flat enough to be surfaced two sides
Physical Characteristics of Wood
Boards must be flat enough to be surfaced two sides
Physical Characteristics of Wood
Shake – Lengthwise separation of wood along the growth rings
(Not permitted on the clear face)
Pith – Spongy core at the center of the tree (Not permitted on the clear face)
Physical Characteristics of Wood
Wane – Bark or lack of wood (Not permitted on the clear face) Splits – Lengthwise
separations(Not permitted on the clear face)
Decay- Also called rot or dote (Not permitted on the clear face)
Grading Hardwood Lumber
Standard Grades FAS (Firsts and seconds) FAS 1F (Firsts and seconds one
face) #1 common on poor face Selects #1 Common #2 Common #3 common
Grading Hardwood Lumber
Yields needed to make grade
FAS – 83 1/3%
#1Common – 66 2/3%
#2 Common – 50%
#3 Common – 33 1/3%
Grading Hardwood Lumber
How do you determine yield?1. Determine the species2. Determine the surface measure (width”
x length’)/123. Determine the poor side of the board4. Assign a “trial” grade to the poor face,
based on your estimate of clear wood5. Determine the number of cuttings
permitted in the trial grade6. Determine the clear face cuttings needed
(SM x the multiplier for the grade)
Grading Hardwood Lumber
7. Calculate the total area of clear-face cutting units on the poor face
8. If the board does not yield sufficiently, try the next grade down.
Grading Hardwood Lumber
Example: Trial Grade FAS
1. Determine Surface Measure
(12 x12)/12 = 12
Grading Hardwood Lumber
2. Determine the number of cutting permitted.12/4 = 3 cuttings
3. Determine the minimum size of cuttings4”x 5’ 3”x 7’
4. Determine the clear face cutting units needed. 12 x 10 = 120 units
Grading Hardwood Lumber
Cutting #1 6” x 7’ = 42 cutting units Cutting #2 6” x 6 ½ = 39 cutting units Cutting #3 8” x 5’ = 40 cutting units
Total 121> 120 ok
Grading Hardwood Lumber
Determine SM for board Determine the clear-face cuttings needed Determine the minimum size of cuttings Determine the number of cuttings allowed Calculate the total area of clear-face cutting units Compare answer to cutting needed
How Lumber & Veneer Is Cut
ROTARY $
PLAIN SLICE $$
RIFT CUT $$$
QUARTER SAWN $$$$
R IFT CUT
HOW LUMBER IS CUT
QUA R TER SAWN
PLAIN SLICED
PLAIN SLICED
HOW LUMBER IS CUT
QUA R TER SAWN
R IFT CUT
PLAIN SLICE0 ° TO 3 0 °
3 0 ° TO 6 0 °
6 0 ° TO 9 0 °
PANEL PRODUCTS
PANEL PRODUCTS
PANEL PRODUCTS
PANEL PRODUCTS
PANEL PRODUCTS
PANEL PRODUCTS
PANEL PRODUCTS
Veneer Grade – Describes the natural and other characteristics allowed in the veneer. Appearance defines grade
Face Grade Back Grade Veneer Grade
PANEL PRODUCTS AA GRADE – The best quality face grade
for high end use
A GRADE –Where AA is not required but excellent appearance is important
B GRADE – Where the natural characteristics and appearance of the species are desirable
C, D & E GRADES – Provide sound surfaces but allow unlimited color variation
PANEL PRODUCTS
BACK GRADES
Back grades are designated by numbers:1, 2, 3 & 4
Requirements of grade 1 are the most restrictive, with grades 2, 3 and 4 being progressively less restrictive.
PANEL PRODUCTS
VENEER INNER PLY GRADES
Four inner ply grades are within the following letter designations : J, K, L & M
J is the most restrictive allowing minimal size openings. K, L and M are progressively less restrictive.
HOW VENEER IS CUT
HOW VENEER IS CUT
FL ITCH
LEA F
LEA F
B OO K
HOW VENEER IS CUT
HOW VENEER IS CUT
PANEL PRODUCTS
MATCHING
PANEL PRODUCTS
PANEL PRODUCTS
PANEL PRODUCTS
MATCHING WITHIN INDIVIDUAL PANEL FACES
PANEL PRODUCTS
PANEL PRODUCTS
PANEL PRODUCTS
OTHER PANEL PRODUCTS
INDUSTRIAL PARTICLE BOARD Low Density Medium Density High Density
MDF – Medium density fiberboard MELAMINE – High density particle board or
mdf with water based resin sheet covering fused with heat, adhesive and pressure
POLYESTER –Same as melamine except oil based sheet covering
OTHER PANEL PRODUCTS
Core Types Fir Core Pine Core Wheat Core Soy Core (New)
OTHER PANEL PRODUCTS
VINYL
PAINTED HARDWOOD
MASONITE
OTHER PANEL PRODUCTS
THICKNESS 1/4” 3/8” 1/2” 5/8” 3/4” 1”
OTHER PANEL PRODUCTS
WIDTH AND LENGTH 4’X8’ 8’X4’ 4’X10’ 4’X12’