HARDWOOD LUMBER
CROSS SECTION OF A TREE
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” thick Lumber thickness is expressed in quarters
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”) 15/16” 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”
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”
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 Decay- Also called rot or dote
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? 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)
Grading Hardwood Lumber 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.
Example: Trial Grade FAS Determine Surface Measure (12 x12)/12 = 12
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
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%
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 121 > 120 ok
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
How Lumber & Veneer Is Cut ROTARY (Panel Products Only) $ PLAIN SLICE $$ RIFT CUT $$$ QUARTER SAWN $$$$
HOW LUMBER IS CUT
HOW LUMBER IS CUT
Break Time
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
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’