hardwood lumber. cross section of a tree grading hardwoods hardwood lumber is graded on the basis of...

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’