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HARDWOOD LUMBER
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CROSS SECTION OF A TREE
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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
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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
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How Lumber Is Sold Rough S2S (Surfaced two sides)
S4S (Surfaced four sides) Rough lumber starts at 1” thick Lumber thickness is expressed in quarters
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Lumber Expressed in Quarters
Thickness Rough Surfaced AWI 1” 4/4 13/16” (3/4 “) 11/16” 1 1/4” 5/4 1 1/16” (1”) /16” 11/2” 6/4 1 5/16” (1 1/4”) 1 3/16” 1 3/4” 7/4 1 1/2” (1 3/8”) 1 ¼” 2” 8/4 (1 1/2”) 1 ½”
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1” 11/16” 2” 1 ½” 3” 2 ½” 4” 3 ½” 5” 4 ¼” 6” 5 ¼” 8” 7” 10” 9”
NOMINAL WIDTH FINISHED WIDTHS OF S4S 1” 11/16” 2” 1 ½” 3” 2 ½” 4” 3 ½” 5” 4 ¼” 6” 5 ¼” 8” 7” 10” 9”
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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.
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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
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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
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Physical Characteristics of Wood
Boards must be flat enough to be surfaced two sides
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Physical Characteristics of Wood
Boards must be flat enough to be surfaced two sides
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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)
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Physical Characteristics of Wood
Wane – Bark or lack of wood (Not permitted on the clear face) Splits – Lengthwise separations Decay- Also called rot or dote
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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
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Grading Hardwood Lumber
Yields needed to make grade FAS – 83 1/3% #1Common – 66 2/3% #2 Common – 50% #3 Common – 33 1/3%
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Grading Hardwood Lumber
How do you determine yield? Determine the species Determine the surface measure (width” x length’)/12 Determine the poor side of the board Assign a “trial” grade to the poor face, based on your estimate of clear wood Determine the number of cuttings permitted in the trial grade Determine the clear face cuttings needed (SM x the multiplier for the grade)
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Grading Hardwood Lumber
Calculate the total area of clear-face cutting units on the poor face. If the board does not yield sufficiently, try the next grade down.
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Example: Trial Grade FAS
Determine Surface Measure (12 x12)/12 = 12
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Example: Trial Grade FAS
2. Assign a “trial” grade to the poor face, based on your estimate of clear wood FAS 3. Determine the number of cutting permitted. 12/4 = 3 cuttings
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Example: Trial Grade FAS
4. Determine the minimum size of cuttings 4”x 5’ 3”x 7’ 5. Determine the clear face cutting units needed. 12 x 10 = 120 units. 83 1/3%
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Example: Trial Grade FAS
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 > 120 ok
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Example: Trial Grade No 1. Common
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
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How Lumber & Veneer Is Cut
ROTARY (Panel Products Only) $ PLAIN SLICE $$ RIFT CUT $$$ QUARTER SAWN $$$$
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HOW LUMBER IS CUT
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HOW LUMBER IS CUT
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Break Time
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PANEL PRODUCTS
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PANEL PRODUCTS
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PANEL PRODUCTS
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PANEL PRODUCTS
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PANEL PRODUCTS
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PANEL PRODUCTS
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PANEL PRODUCTS Veneer Grade – Describes the natural and other characteristics allowed in the veneer. Appearance defines grade Face Grade Back Grade Veneer Grade
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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
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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.
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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.
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HOW VENEER IS CUT
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HOW VENEER IS CUT
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HOW VENEER IS CUT
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HOW VENEER IS CUT
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PANEL PRODUCTS MATCHING
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PANEL PRODUCTS
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PANEL PRODUCTS
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PANEL PRODUCTS MATCHING WITHIN INDIVIDUAL PANEL FACES
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PANEL PRODUCTS
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PANEL PRODUCTS
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PANEL PRODUCTS
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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
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OTHER PANEL PRODUCTS Core Types Fir Core Pine Core Wheat Core
Soy Core (New)
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OTHER PANEL PRODUCTS VINYL PAINTED HARDWOOD MASONITE
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OTHER PANEL PRODUCTS THICKNESS 1/4” 3/8” 1/2” 5/8” 3/4” 1”
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OTHER PANEL PRODUCTS WIDTH AND LENGTH 4’X8’ 8’X4’ 4’X10’ 4’X12’
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