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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.
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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
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
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? • 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 • If the board does not yield sufficiently, try the next grade down.
Grading Hardwood Lumber • Example: Trial Grade FAS • 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 cuttings 4”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 $$$$
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.
PANEL PRODUCTS MATCHING
PANEL PRODUCTS MATCHING WITHIN INDIVIDUAL PANEL FACES
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’
