Wood properties and process report

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Title:
Wood properties and process report
Physical Description:
Mixed Material
Language:
English
Creator:
Fraga, Robert
Publisher:
Robert Fraga
Place of Publication:
Gainesville, FL
Publication Date:

Notes

General Note:
AFA HP document 858

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Source Institution:
University of Florida
Holding Location:
University of Florida
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All rights reserved by the source institution.
System ID:
AA00001630:00001

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WOOD PROPERTIES AND PROCESS
REPORT
ROBERT FRAGA. AE 681















BIBLIOGRAPHY.

TI TLE AUTHOR DAfTE

MATERIALS OF CONSTRUCTION R.C. SMITH. MCGRAW HILL CO.
CHAP. 1 PAG 1- 46 1966

OLD WAYS OF WORKING WOOD A. W. BEALER. BARRE PUBLISHERS
1972

HOW TO BUILD YOUR OWN FURNITURE R. J. DECRISTOFORO HARPER &
ROW 1968



THE FOLLOWING ARE REPEREICES THAT MIGHT BE HELPPUT FOR FURTHER
INVESTIGATION OF THE SUBJECT.

MATERIALS AND METHODS OF CONSTRUCTION. PARKER, GAY AND MCGUIRE.
1958
BUILDING CONSTRUCTION HUNTINGTON 1963

CONSTRUCTION: PRINCIPALS, MATERIALS AND METHODS. SCHMIDT, OLIN
AND LEWIS 1972







WOOD PROPERTIES AND PROCESSING.


WHY WOOD IS USED ARCHITECTURAL?
A) IT IS ABUNDANT
B) EASILY WORKED, DURABLE AND BEAUTIFUL

C) WOOD IS GOOD IN TENSION AS WELL AS IN COMPRESSION
D) ABSORBS SHOCKS PROM SUDDEN LOADS WELL
E) IT IS RUST FREE
F) IT IS LIGHTWEIGHT AND ADAPTS TO COUNTLESS USES


STRUCTURE OF WOOD

T72AS GROW FROM INSIDE OUT, GROWING BY ADJDIPI /IE YATIALL TO
TPIR OUTER LAYERS JUST UNDER THE BARK AND PRESS rViDG C OLDYR
FIBERS AS IT ADDS NEW ONES.

CROSS SECTION OF A TREE ( DRAWING )
A) BARK: OUTER COVER
E) Cl uLIUM LAYER: WHERE GROWS TAKES PLACE THIS OCCURS RIf I'-
UNDER THE BARK

C) ANNUAL RINGS: EACH RING REPRESENTS A YEAR O GCRO .WTHI THE

RINGS ARE MADE OUT OF: SPRINGWOOD .A ) ; .
WOOD. SPRING WOOD ARE THE' WIDER F;I' ./ THAT

RESULT FROM FASTER GROWTH DURING TET 7TF TG

Ui,1MBERWOOD: ARE MSALLER AND HARJ.EP DU"T TO SLOW
GROWTH DURING THE SUMMER.

LIGNIN: SUBSTANCE THAT BONDS TOGETHER THE TREE CELLS VIKICH IN
TERM ARE BUNDLED IN FIBERS THAT CARRY THE F0j) I:I.T-RIAL
FROM ROOT TO LEAVES.







THE- TREE DIES FROM INSIDE OUT SO THAT THE INTERIOR FIBERS
OF THE TREE SERVE TO GIVE STRUCTURAL STIFFNESS TO THE TREE

HEARTWOOOD: THE LAYERS OF TREE CELLS WHICH ARE LOCATED IN THE
CENTER OF THE TREE, IT IS USUALLY DARKER IN COLOR
AND HARDER. ( DEADWOOD)
SAPWOOD THE LIVING PART OF THE TREE WHICH IS GENERALLY NOT
AS HARD AND IT IS LOCATED IN THE OUTER RINGS OF THE
TREE.

THERE ARE MANY TEXTBOOKS WHICH PROVIDE FOR DESCRIPTIONS OF
THE PROPERTIES AND USES OF THE MOST COMMON TREES.

GENERAL CLASSIFICATION OF TREES.
HARDWOODS: THESE ARE DECIDIOUS TREES SHED THE LEAVES DURING THE
FALL. EX. OAK MAPLE, ASH.
SOFTWOOD: EVERGREEN CALLED CONIFERS, THESE TREES BEAR THEIR
SEEDS IN CONES. EX. PINE, SPRUCE, REDWOOD.

THE TERMS HARDWOODS/ SOFTWOODS ARE NOT INDICATIVE OF THE
ACTUAL STRENBHT OF THE WOOD OF THE TREE.

PROBLEMS DEALINGS WITH WOOD. (MOISTURE AND GRAIN)

BEFORE WOOD IS U3STD FOR ARCHITECTURAL PURPOSES, SOME OF THE
MOISTURE FROM THE WOOD HAS TO BE REMOVED FOR THE FOLLOWING
REASONS.
A) IT MAKES IT EASIER TO WORK WITH THE WOOD ( LIGHTER )
B) IT PROTECTS THE WOOD FROM PARASITES

C) IT PROTECTS THE WOOD FROM WARPING AFTER IT HAS BEEN USED
IN CONSTRUCTION.






THERE ARE TWO TYPES OF MOISTURE, HYIGROSCOPIC MOISTURE WHICH
IS MOISTURE INSIDE THE CELL, AND FREE MOISTURE WHICH IS FOUND
OUTSIDE THE TREE CELL. THE HYGROSCOPIC MOISTURE ESCAPES AFTER
THE FREE MOISTURE HAS LEFT THE WOOD.

MOISTURE CONTENT:
FORMULA. (%) ORIGINAL WEIGHT OVEN DRY WEIGHT (100)
OVEN DRY WEIGHT

THERE ARE TWO WAYS OF ELIMINATING MOISTURE FROM THE WOOD.
AIR DRY REDUCES MOISTURE TO 15%
KILN DRY OVENDRY THE MOISTURE IS REDUCED PROM 5 TO lo %

NOTE. THERE IS ALWAYS MOISTURE LEFT ON THE WOOD

GRAIN.
GRAIN REFERS TO THE APPEARANCE OF A PIECE OF WOOD IN ONE OF
ITS CUT SURFACES.
THREE MOST COMMON GRAINS.
EDGE GRAIN: THE ANNUAL RINGS RUN AT RIGHT ANGLES TO THE FACE
OF THE BOARD. ( DRAWING )
FLAT GRAIN: ANNUALS RINGS RUN PARALLEL TO THE SURFACE OF THE FACE
OF THE BOARD. ( DRAWING)
ANGLE GRAIN: WHEN THE ANNUAL RINDS RUN AT AN ANGLE OF APPROX.
45 DEGREES TO THE FACE OF THE BOARD.

OTHER TYPES OF GRAIN. CLOSED GRAIN, MEDIUM GRAIN, COARSE GRAIN.

THE GRAIN CLASSIFICATION IS USED NOT ONLY TO DETERMINE WHAT
PIECES OP WOOD TO USE FOR PARTICULAR FINISHES BUT ALSO IN THE


SELECTION OF STRUCTURAL LUMBER.







WOOD PROCESSING,


THE PROCEDURE OF WOOD MANUFACTURE HAS CHANGED VERY LITTLE
ONLY THE TECHNOLOGY HAS CHANGED. THE PROCESS IS BASICALLY AS
FOLLOWS:
LOGGING OPERATION. CONVERTING STANDING TREES INTO SAWLOGS
GETTING THE SAWLOGS READY FOR THE SAWMILL.

THE LOGGING OPERATIONS VARY ACCORDING TO THE TOPOGRAPHY OF

THE SITE, BUT THE GENERAL PRINCIPALS ARE AS FOLLOWS:

A) FELLING: TREES ARE BROUGHT DOWN WITH AN AX OR SAW.
B) BUCKING: CUT OF THE BRANCHES AND CUT THE LOGS INTO 12 TO
40 FT. PIECES.
C) SKIDDING: MOVING LOGS TO THE SKIDWAY (ASSEMBLY POINT)
D) HAULING: LOGS TRANSPORTED TO THE MILL.

PROCESS.
THE TREES ARE MARKED AND FELLED. AFTERWARDS A CREW COMES TO
PERFORM THE BUCKING OR LIMBING OPERATIONS, WHICH IS TO REMOVE THE
BRANCHES AND TO CUT THE LOGS INTO 12 TO 40 FT. LONG J'TSCES.
THE LOGS ARE THEN MOVE TO A SKIDWAY WHICH IS THE PLACE WHERE

THE LOGS ARE ASSEMBLED TO BE CARRIED OFF TO THE MILL. THIS

PROCESS IS CALLED SKIDDING AND THE METHOD OF TRANSPORTATION

WILL DEPEND MAINLY ON THE TERRAIN, ( CRAWLER TRACTORS, HIGH-
lINE RIGGED TO A SPAR TREE, ETC. )
LOGS CAN BE TRANSPORTED IN RAILWAY FLATCARS, TRUCKS, ETC.

ON THE MILL.
THE LOGS ARE PUT THROUGH A BARKER WHICH REMOVES THE BARK AND
THE LEAVES AND LEAVES THE LOGS CLEAN FOR THE FOR THE SAW.






INCIPIENT DECAY.
THESE IS THE RESULT OF THE EARLY GROWTH THE FUNGUS AND IT
SHOWS IN A FORM OF DECOLORATION BUT IT CEASES TO BE ACTIVE APTER
THE WOOD HAS BEEN SEASONED. IT DOES NOT A.FECT THI STRENGTH OF
THE WOOD.

ADVANCED DECAY.
SERIOUS DESTRUCTIVE ACTION CAN BE SEEN IN THE FORM OF BROWN
ROT. IT DOES AFFECT THE STRENGTH OF THE WOOD.

THE PROBLEMS OF WOOD DESEASES IS ONE OF PREVENTION RATHER THAN
CURE. SEASONING WOOD AND TREATING IT WITH TOXIC MATERIALS
ALWAYS HELPS.

LUMBER DEFECTS.
THESE ARE THE MOST COMMON TYPES OP DEFECTS THAT OCCUR AS A

RESULT OF SEASONING, DESAESES OR POOR GROWTH OF THE WOOD.
(DRAWINGS)
CHECK OR CRACK CRACKS DEVELOP FROM SEASONING THE WOOD.
SHAKE WHEN ONE OF THE ANNUAL RINGS HAS SKIPPED PART OF THE
CIRCUNSPERENCE OF THE TRUNK LEAVING A GAP.
KNOT THESE IS A DEFECT DUE TO POOR GROWTH OF THE WOOD. THEY
CAN BE LOOSE KNOTS OR SOLID.
PITCH POCKET. WHEN THE WOOD IS FOUND IN A LIQUID STATE.

WANE. THESE DEFECTS ARE DUE TO A POOR CUT OF THR WOOD, THE
WOOD IS NOT PERFECTLY SHAPED.


WOOD TREATMENTS.

MOISTURE TREATMENT. THIS TREATMENT IS APPLIED WHEN THE WOOD

IS GOING TO BE CLOSE TO WATER OR EXPOSED TO EXTREME MOISTURE


CONDITIONS.






CREOSOTE OR TAR APPLIED IN 4 METHODS.
A) PRESSURE TREATMENT. (THE BEST)
P) HOT AND COLD METHOD
C) DIPPING METHOD.
D) BRUSHING METHOD.

TREATMENT AGAINST TERMITES.

YOU CAN NOT PREVITT TERMITES BUT RATHER CONTROL THEM. THERE ARE
TWO TYPES OF TERMITES DRYWOOD AND SUBTERRANEAN TERMITES.
SUBTERRANEAN TERMITES ATTACK STRUCTURAL ELEMENTS AND THEY
LIVE IN A DARK AND DAMP ENVIRONMENT.
SIX THINGS TO DO TO PREVENT TERMITES.

A) ELIMINATE WATER FROM THE FOUNDATION AND VENTILATE THE
V FOUNDATIONS

B) UNTREATED WOOD SHOULD NOT BE ALLOWED TO BECOME IN CONTACT

WITH CONSTRUCTION `VOOD.

C) REMOVE ALL LUMBER AFTER CONSTRUCTION.
D) ANY WOOD COMING INTO THE CONSTRUCTION SITE SHOULD BE
INSPECTED
E) PROVIDE FOR A TERMITE SHIELD, CHECK FOR CRACKS IN THE
CONCRETE.
F) POISON AND CLEAR THE SITE BEFORE CONSTRUCTION.


GRADING WOOD.
THE GRADING SYSTEM USED IN THE UNITED STATES IN ORDER TO
DETTERMINE THE QUALITY OF THE WOOD IS BASED ON A LETTER SYSTEM
FROM A D WHERE A IS THE BEST AND 3 IS THE WOBST, ( THIS IS
DETERMINED BT THE NUMBER OF DEFECTS THAT ARE FOUND ON THE WOOD)














HOWEVER, FOR GRADING STRUCTURAL LUMBER THE SYSTEM IS DIFFERENT

STRUCTURAL LUMBER.
CLASSIFICATIONS.
DEISE SELECT STRUCTURAL
SELECT STRUCTURAL
DENSE CONSTRUCTION
CONSTRUCTION

STANDARD.
THE CRITERIA FOR GRADING STRUCTURAL WOOD IS THE FOLLOWINGs
BENDING STRESS, STAIN SAPWOOD, NUMBER OF SPLITS AND NUMBER
OF CRACKS.

LUMBER TALLYING.
IN THE UNITED STATES PRACTICALLY ALL LUMBER IS SOLD BY TIL
BOARD MEASURE, A PIECE OF LUMBER 12 IN WIDE, 1 IN THICK AND
1PFT LONG.


WOOD 15 IoD FOR ARCHITECTURAL PURPOSES IN PORMii UOTHiE d 'mA
IN ITS NATURAL STATE, FOR EXAlfPLE, LAMINATED WOOD, BOX BE-AMS,
ETC.







OLD WAXS OF WORKING WITH WOOD.


WOOD IS BASICALLY BEING USED FOR THE SAME FOR THE SAME PURPOSES
THAT IT HAS BEEN USED FOR HUNDREDS OF YEARS, BUT THE MAIN DI-
JPFERENCE IS THAT 2.10ODERIi lIAl RELIES ON POWER TOOLS WHERE AS
PRIMITIVE MAN USED HAND TOOLS.
THE WORKING TOOLS BECAME VERY I PORTANT SINCE MANY TIMES THE
CRAFTMEN DESIGNED THEIR OWN TOOLS, INDIVIDUALITY WAS VERY
IMPORTANT.

MACHINES ARE NOT AS FLEXIBLE AS HAND TOOLS SINCE THEY ARE

DESIGNED FOR MASS PRODUCTION, AND THE WORKER OF A MACHINE

IS MORE OF AN OPERATOR THAN A CRAFTMAN.


WAYS OF FELLING A TREE.
THE M.iOST PU'U.bUA. WA T FELL A TREE WAS WITH THE AX, THE AX
BEING ONE OF THE MOST IUFORTANT AND OLDEST TOOL USED BY MEN.
THE TWO MEN CROSSCUT SAW WAS VERY POPULAR UN TIL THE MIDDLE OF
THE 20TH UENTURX WH-I1 IT WAS REPLACED Bi THE CHAlIi SAW. IN
EARLY AMERICA, MOST FELLING WAS DONE WITH AN 1K AND BX ONE MAN.

R-lINCIPALS OF FILLING
E OF THE MAIN PROBLEMS WITH FELLING A TREE IS TO GUIDE IT
SO THAT IT FALLS IN THE PLACE DESIRED WY THE WOODSMAN. GUIDING
''J7 TREE IS DONkE BY MEANS OF 2 CUTS OR KERFS ON OPPOSITE SIDES
OF THE TREE. (SLIDE)
1ST CUT 2/5 THE TRUNKS DIAMETER
21TD CUT SHOULD PENETRATE SLIGHTLY UNDER THE FIRST CUT.

THE AXMAN HAS TO COMPENSATE. FOR MANY FACTORS IF HE 'WAjI1.3 THE TREE
TO FALL IN THE RIGHT DIRECTION. WEIGHT OF THE LIM99 PREVAILING
WINDS, AND IF THE TRE IS NOT STRAIGHT. THIS COMPENSATION IS
DONE BY MEANS OF THE CUT.








FIRST, THE LOGS GO THROUGH A HEADSAW, WHICH IS EITHER A
LARGE CIRCULAR SAW OR A BANDSAW, THE HEADSAW CUTS THE LOG IN
VARIOUS PIECES DEPENDING ON THE SIDE BF THE LOG.
LOGS MAY BE CUT INTO BOARDS OR PLANKS, DESIGNATED IN QUARTERS.
1 IN. EQUAL TO 4 QUARTERS, ETC. LOGS MAY BE CUT INTO SQUARE
TIMBER 01 VARIOUS SIZES ( CALLED CAIT ) AND THEY MUST BE

RESAWN INTO BOARDS OR PLANKS.

CATEGORIES SOFTWOOD LUMBER TYPES.

SOFTWOODS ARE PUT INTO THESE CATEGORIES ACCORDING TO THEIR
EVENTUAL USE.

YARD LUMBER. IS MADE TO USE IN ORDINARY LIGHTCONSTRUCTION
AND FINISHING WORK. THE WOOD IS CUT INTO 1 IN
OR 2 IN. COMMON BOARDS.

SHOP LUMBER. IT IS USUALLY LEFT IN 1IN TO 2 IN ROUGH THICIHBESS
OFTEN CONTAINING KNOTS AND OTHER DEFECTS, IT IS
USED FOR MAKING DOOR CABINETS AND SABH.

STRUrTURAL LUMBER. IT IS FOR HEAVY CONSTRUCTION, LOAD BEAR-
ING PURPOSES. ( CUT IN 3 IN OR LATER)
USUALLY OF THE HEARTWOOD OF THE LOG.

WOOD DESEASES AND LUMBER DEFECTS.
VARIOUS TYPES OF FUNGI ARE THE MAIN SOUR OF WOOD D~F'3kASE
WHICH TDrINTEGRATE THE CELL WALL OF THE LOG AND WVAKT'U THE
C. TR-e N-1 D TEXTURE OF THE WOOD. THE MOST COMMON WOOD DISEASES
ARE; SAP STAIN, MOLD, AND WOOD ROT. THERE ARE TWO CLASSIFICATION
AS TO THE DESTRUCTIVENESS CAUSED BY FUNGI. THESE ARE:






SOMETIMES THE WOODSMEN WOULD USE A SPRING POLE TO FURTHER
GuIDE THE THEE IN THE RIGHT DIRECTION. (DRAWING SLIDE)

THERE IS NO REAL DIFFERENCE IN FELLING A TREE WITH AN AX OR A
CROSSSAW. HOWEVER, WITH THE CROSSSAW YOU HAVE TO WORRY ABOUT
LUBRICATION AND USING A WEDGE OF HARDWOOD OR IRON TO GIVE SOME
CLEARANCE TO THE BLADE.
IT IS BETTER TO FELL A SMALL TREE WITH AN AX AND A BIGGER TREE
WITH A SAW.

BUCKING. AF TER FELLING THE TREE, THE WOODSMEN CUT THE LOGSIN
VARIOUS PIECES RANGING FROM 6 TO 20 FT. WHICH WERE
TRANSPORTED TO THE SAWMILL BY OXEN OR LUMBER CARTS
( AN AXLE WITH TWO HUGE WHEELS )

TYPES OF AXES.

THERE ARE SEVERAL TYPES OF AXES, SMALL BIG, LONG HANDLE HEAVY
HANDLED, ETC. T'HIY ARE USED FOR VARIOUS TASKS, SPLITTING, FELLING
MAKING SHINGLES,ETC. THE HANDLE VARIED ACCORDING TO THE PURPOSE.

4 MOVEMENTS FOR SHOPPING WITH AN AX.
A) LIFTING
B) SWINGING
C) DISENGAGING
D) RECOVERY

SAWS.
SAhJ; ARE ALSO VERY OLD TOOLS. (STONE AGE, SHARK TEETH) EARLY SAWS
*W-.dE NOT VERY EFFICIENT.
CROSSCUT SAWS.
DESIGN TO CUT TRANSVERSELY THRU THE TREE ( TO CUT BACK AND FORTH)
THE WOOD PARTICLES AND THE SAWDUST WAS REMOVED BY THE MOTION OF
THE SAW.




SAWING.
INVOLVES TWO MEN WHO EACH PULL THE SAW TOWARDS THEIR SIDE
NEVER PUSHING OR HOLDING BACK. SAWYERS USE THEIR UPPER BOBY
AS THE SOURCE OF STRENGTH FOR SAWING, VARIOUS POSITIONS ARE
USED IN SAWING DEPENDING ON THE TERRAIN.

SPLITTING.
MOST TREES GROW IN PARALLEL FIBERS WHICH CAN BE SEPARATED
EASILY BY SPLITTING. SPLITIIG WAS USED FOR MAKING FENCE POST,
SHINGLES, LATH FOR PLASTER, CLAPBOARDS. ETC. ( IT DESAPEAR AFTER
WWII ).
NOT EVERY TREE IS SUITABLE FOR SPLITTING, SEVERAL TYPES OF OAKS
ARE VERY GOOD.

TOOLS FOR SPLITTING.
SMALL AXES ARE USED FOR SPLITTING, THE BEST ARE THE AMERICAN
SINGLE BLADE AX AND THE EUROPEAN HOLZAXT, A VERY HEAVY IRON OR
STEEL WEDGE PIERCED LIKE AN AX FOR A HANDLE.
OTHER TOOLS USED IN SPLITTING WERE THEIR WEDGE AND THE FROE. THE FROE
BEING AN INSTRUMENT THAT IS DRIVEN INTO THE WOOD BILLETS WITH THE
HELP OF A FORK AND A SHORT MAUL.
HEWING
ADZ AND BROADAX* THESE WERE THE FIRST FINISHING TOOLS, GENERATED
THE CHISEL AND THE DRAWKNIFE, SAW AND PLANE.
THE ADZ WAS WRED FOR ROUGH DRESSING TIMBER, TO REMOVE THE BARK
OF THE TREE AND SQUARE OF THE LUMBER FOR ITS USE IN1 A LOG CABIN

BORING
MOST OF THE INSTRUMENTS THAT WERE USED FOR BORING HAVE PEEDJ
REPLACED BY THE ELECTRIC DRILL.
TOOLS.
AW&. SLIM STEEL ROD 2 !/2 IN. LONG INSERTED IN A SPHERICAL
HANDLE
PT-MP DRILL
BOW DRILL GENERALLY USED FOR SMALL HOLES ON A CONTINIU03 MOTION
AUG J R' USED FOR BIGGER HOLES, FUNCTION LIKE A CORK SCREW.