WOODWORKING

Technology Education Dept.

Bellwood-Antis Middle School

Mr. Mackereth

ADVANTAGES OF USING LUMBER & WOOD PRODUCTS

• WHY MAKE THINGS OUT OF WOOD?• Wood is both STRONG & LIGHTWEIGHT.

• Wood is BEAUTIFUL & ATTRACTIVE.

• Wood is from a RENWEABLE RESOURCE.

• Wood can easily be CUT, SHAPED, SANDED, and SEALED.

• Wood COSTS LESS than other materials.

OLDER HARVESTING METHODS

• For hundreds of years, companies harvested timber in the forest using CLEARCUTTING.

• This method CUT DOWN EVERY TREE in the forest, leaving the land bare and ruined.

• Soil eroded during rainstorms forming gullies.• Wildlife (land animals) had no place to live.• Soil and mudslides polluted the streams.• Aquatic life (fish and reptiles) were killed.• In general, CLEARCUTTING RUINED THE FOREST!

LOGGING METHODS INTODAY’S WORLD

• Today’s lumber & logging companies practiceREFORESTATION (regrow, replant) in the woods.• A. SELECTIVE CUTTING- We cut ONLY a certain

kind of tree, or trees of a certain diameter • B. PLANTING TREE SEEDLINGS- We replant tree

seedlings after we are done logging for the future.• C. SOIL & WATER CONSERVATION- We make sure

that no soil enters the streams and rivers, or that none of the water resources are polluted.

LOGGING METHODS INTODAY’S WORLD (cont.)

• Today’s lumber & logging companies practiceREFORESTATION (regrow, replant) in the woods.• D. LUMBER BY PRODUCTS- We make solid lumber

products out of the scraps left over from the mill. This includes OSB, mulch bark, or composites.

• E. RECYCLING PAPER- The more paper we recycle, the less trees need to be cut down for paper!

• EVERYONE PITCHING IN & DOING THEIR PART HELPS OUR FOREST RESOURCES!

PHYSICAL CHARACTERISTICS OF TREES AND LUMBER PRODUCTS

• Living trees are made up of CELLS, just like the human body. When the tree is harvested for lumber, cut at the mill, and dried, these cells…..

• are called WOOD FIBERS. A collection of the• wood fibers is called the GRAIN of the wood.

• Cutting with the grain is called RIPPING.

• Cutting across the grain is called CROSS CUTTING.

PARTS OF A TREE• 1- OUTER BARK

• 2- INNER BARK

• 3- CAMBIUM CELLS

• 4- SAPWOOD

• 5- HEARTWOOD

• 6- PITH (young tree)

FUNCTION(S) OF TREE PARTS

• OUTER BARK- Protects the inside of the tree• INNER BARK- Transports food (sugar, sap) up the

tree in winter/early spring, down during rest of time• CAMBIUM CELLS- Growth cells that multiply and

divide to create new layers (annual rings) in the tree• SAPWOOD-Transports water & minerals up the tree• HEARTWOOD- Center most part of the tree, gives

the tree strength and color.

TYPES OF TREES• HARDWOOD SPECIES- trees that have flat, blade-

like leaves, and loose their leaves every year.• Examples of HARDWOODS: OAK MAPLE• POPLAR BASSWOOD WALNUT

CHERRY• SOFTWOOD SPECIES- Trees with needle-like leaves

and cones, keep their needles for more than 3 years• Examples of SOFTWOODS: PINE

SPRUCE• HEMLOCK RED CEDAR DOUGLAS FIR

ANY QUESTIONS?• This concludes part one of the wood notes.

• COMPLETE THE REVIEW WORKSHEET FOR THESE PAGES OF NOTES (Due on___________)

• STUDY FOR THE QUIZ!

• AS SOON AS YOU TAKE AND PASS YOUR QUIZ, YOU WILL BE WORKING IN SHOP!

SAWING LUMBER IN A MILL

• At the mill, lumber can be cut in two ways:• PLAIN SAWING- The WHOLE log gets placed on

the carriage and “sliced” into boards.• Plain sawing is used for common lumber, but it

bows, warps, and twists easily (out of shape.)• QUARTER SAWING- The log gets cut into

quarters, and the ¼ log is “sliced” into boards.• Quarter Sawing is used for EXPENSIVE lumber. It

does not usually bow, takes more work, time, $.

SAWING LUMBER IN A MILL (cont.)

• The pieces that are cut off of the logs are called• SLABS, & some still have the BARK left on the edges• Those with bark edges are sent through an EDGER

to remove bark make all the edges straight & true.• The edged boards are sent through TRIMMER or

CROSSCUT saws to SQUARE the ENDS.• The trimmed boards are usually cut into lengths of

8, 10, 12, or 16 feet making them easier to ship.• The fresh cut boards are now called GREEN LUMBER

PROCESSING BOARDS IN THE MILL• After sawing, the lumber enters the GREEN CHAIN.• The lumber is SORTED into different GRADES based

upon the APPEARANCE of the board & the presence of DEFECTS that effect the GRADE of the board.

• Next ALL LUMBER is AIR DRIED outside to remove SOME, but not ALL, of the moisture content.

• HIGHER GRADE LUMBER is then KILN DRIED in a CLOSED, HEATED building (removing more moisture)

• Boards are FINISHED drying at about 6% MOISTURE.

PROCESSING BOARDS (cont)

• HARWOOD LUMBER GRADES are:• SELECT FIRST SECOND• HARWOOD LUMBER GRADES are:• SELECT FIRST COMMON SECOND

COMMON• Defects that can be found in lumber include:• BOWING (warping) KNOTS PITCH

POCKETS• METAL CONTENT CRACKS WANE

EDGES

COMMON LUMBER PRODUCTS

• BOARDS- used for assorted projects & framing• STUDS- used to frame homes, buildings, and rafters• PLYWOOD- laminated layers/plies glued together in

4 x 8 sheets. Used for walls, roofs, flooring, cabinets• VENEER BOARDS and VENEER PLYWOOD- used to

make interior doors, cabinets, and furniture• VENEER is a term describing the process of taking a

thin layer/ply of SELECT lumber and glue it on top of lower grade, but solid boards (our doors & cabinets)

COMMON LUMBER BY-PRODUCTS

• FLAKEBOARD- “flakes” of wood are glued & pressed together into 4 x 8 sheets. Flakeboard and OSB are used the same way that plywood is used in homes.

• Oriented Strand Board (OSB)- similar to flakeboard, but has a moisture barrier on one, “shiny” side.

• MINERAL CORE BOARD- scrap materials & mineral composite glued/pressed between 2 plies of veneer

• Remember, these are SCRAP products from the mill

WORKING WITH BOARDS IN SHOP

• Lumber used in shop is KILN DRIED FAS (1st & 2nd)• The FIRST STEP is to PLANE them. We use a SINGLE

SURFACE PLANER to shave 1/16” at a time until we have PLANED the board to the EXACT THICKNESS.

• Next, we take the planed board over to the JOINTER to joint 1 EDGE SQUARE with the board’s surface.

• This provides a smooth, jointed edge to slide easily along the fence of the table saw (the next step.)

CUTTING PROJECT PIECES• The 3RD & 4TH steps are done on a TABLE SAW.• We set the fence of this saw to the EXACT WIDTH

we want the board to be when we are finished.• If the board is wide enough for two or more cuts, or

if multiple boards are cut, the saw is set only once.• We push the board CAREFULLY & SLOWLY through

the saw making a RIPPING cut (with the grain.)

CUTTING PROJECT PIECES• The 5th & 6th STEPS can be done on either a RADIAL

ARM SAW (large pieces) or a MITER SAW (small.)• We CAREFULLY TRIM ONE END SQUARE with a

CROSSCUT. This makes the end EVEN & SQUARE.• Then we MEASURE the board to its EXACT LENGTH.• We then place the board back on the saw, and we

CROSSCUT the board to its EXACT LENGTH.

• NOW WE HAVE OUR PROJECT PIECE!

ANY QUESTIONS?• This concludes part one of the wood notes

• COMPLETE THE REVIEW WORKSHEET FOR THESE PAGES OF NOTES (Due on___________)

•STUDY FOR THE QUIZ!• AS SOON AS YOU TAKE AND PASS YOUR

QUIZ, YOU WILL BE WORKING IN SHOP!