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Selecting and Roughing Out Lumber. Kinds of Wood. A. Softwood: Comes from evergreen trees, also called “conifers”. B. Hardwood: Comes from broadleaf trees, also known as “deciduous”. Common Softwoods and Hardwoods Grouped according to hardness. Soft Medium Hard Hard - PowerPoint PPT Presentation
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1. A. Softwood: Comes from evergreen trees, also called “conifers”.
B. Hardwood: Comes from broadleaf trees, also known as “deciduous”.
Common Softwoods and HardwoodsGrouped according to hardness
Soft Medium Hard HardBalsa Cypress White AshBasswood Butternut BeechCottonwood Douglas Fir BirchWhite Fir American Elm Black CherryPonderosa Pine Hemlock HickoryWestern White Pine Limbo Sugar MapleSugar Pine Magnolia Red OakYellow Poplar Mahogany White OakSpruce Prima Vera Black WalnutRedwood Red Cedar TeakBlack Willow Sycamore
2. In addition to hardness or softness, different kinds of wood will vary in:
•Weight•Strength•Color•Texture•Grain pattern•Odor
1. For first projects where you will be using mostly hand tools choose softwoods ie.:basswood pine popular willow
2. With experience where you will be using hand and power tools choose medium hard woods ie:firs butternut hemlock red cedar
3. When your project requires wide widthsof stock, consider using Plywood.
4. Advance projects that will be constructedwith the use of power tools will make it possible to use hardwoods.
oak maple ash hickory
Softwoods Grading:
1. Select grades: A to D, with B and better being the highest grades.
C Select: must be clear on one side
D Select: may contain pin knots and other defects.
2. Common Grades: #1 Common to #5 Common*most often used as structural lumber
Softwoods Grading continued:
3. Factory and Shop Lumber:#1 shop, #2 shop and #3 shop*most often used for door frames and trim.
Hardwood Grading:
1. Firsts and seconds (FAS): must be 6”by 8’ and yield at least 83 1/3% clearcuttings.
2. Selects: permits 4’ by 6’ with more defects on the back surface.
3. Lower grades are #1 common, #2 common, #3 and “shorts”.
1. Defects in Lumber usually lower the strength durability and appearance.
Common Defects:
Knots
Encased Intergrown Spiked
Splits and Checks
Shake
Warps
Crook
Bow
Cup
Twist
1. Softwoods are planed on all surfaces, and sold in specific widths:
From 2” to 12” by 2” intervals andIn lengths 8’ to 20’ by 2 ‘ intervals
2. Because the planing removes some of the wood, the thickness and width will measure less than the sizes listed.
3. Hardwoods can be purchased either rough cut or surfaced on both sides.
4. Hardwoods are not cut to any standard width or length. Instead they are sold inrandom widths and lengths.
Rough and Finished Sizes
SoftwoodRough cut planed1x2 ¾ x 1 ½1x4 ¾ x 3 ½1x6 ¾ x 5 ½2x2 1 ½ x 1 ½2x4 1 ½ x 3 ½2x6 1 ½ x 5 ½4x4 3 ½ x 3 ½
HardwoodRough Planed3/8
3/16½
5/165/8
7/16¾
9/161 13/162 ½ 2
¼3 2 ¾
1. Plywood is constructed by gluing together a number of layers (piles) of wood with the grain directionturned at right angles in each successivelayer.
Faces: the outer pilesCross bands: next layer under the facesCore: inside layer or layers
Plywood layers
2. Two basic types of plywood-interior: used for cabinets and furniture-exterior: bonded with waterproof glues
used in construction
3. Standard panel of plywood is 4’ x 8’and comes in thicknesses of 1/8” to 1”.
1. Hardboard is made of refined fibers, pressed together to form a hard, densematerial.
2. Particle board is made of wood flakes,chips and shavings bonded together withresins and adhesives.
Hardboards and Particle Boards
1. The unit of measure for lumber isthe Board Foot. One board foot is:
1 in. thick and 12 in. square (144 cu. In.)
2. Figuring board footage:all measurements in inches
# pieces of wood X height X Width X Length
1 X 12 X 12Bd. Ft. =
3. For large amounts of lumber, use a board rule.
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