Wood in war and peace

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Title:
Wood in war and peace
Series Title:
Report ;
Physical Description:
11 p. : ; 26 cm.
Language:
English
Creator:
Garratt, George A
Forest Products Laboratory (U.S.)
University of Wisconsin
Publisher:
U.S. Dept. of Agriculture, Forest Service, Forest Products Laboratory
Place of Publication:
Madison, Wis
Publication Date:

Subjects

Subjects / Keywords:
Wood -- Utilization   ( lcsh )
Genre:
federal government publication   ( marcgt )
non-fiction   ( marcgt )

Notes

Statement of Responsibility:
by George A. Garratt.
General Note:
Caption title.
General Note:
"October 1944"--Cover.
General Note:
"In cooperation with the University of Wisconsin"--Cover.

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 029318338
oclc - 755903620
System ID:
AA00020582:00001

Full Text
'I *)


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1~


WOOD IN WAIR ANI PBEACIE

October 1944















*S(
'11tpIOF AGR~LG






No. 11460







UNITED STATES DEPARTMENT OF AGRICULTURE
FOREST SERVICE
FOREST PRODUCTS LABORATORY
Madison, Wisconsin
In Cooperation with the Univcrsity of Wisconsin


" 1







WOOD IN '.'AR A:D PEACE-


By GEORGE A. GARRATT, Chief
Division of Technical Service Training
2
Forest Products Laboratory,- Forest Service
U. S. Department of Agriculture



Our present-day reliance upon wood, not as a temporary wartime
expedient, but in full recognition of its rightful position as a standard
and traditionally important engineering material, affords conspicuous evi-
dence of the striking advances made in wood technology and wood utilization
since '7orld ".ar I. The clearly demonstrated ability of a wide variety of
wood products to fulfill the exacting requirements of many of their current
uses, and the unending search for ways and means of broadening their sphere
of us.:-ful:.ess, offer great promise for the extended utilization of wood in
the rojt,.-,ar period, even in the face of continued improvements in competi-
tive materials.

The impact of wartime requirements has naturally provided a great
stimulus for research in wood utilization and, in fact, has so accelerated
such activity that developments which ordinarily would require years to
attain are being achieved in a matter of months. However, full recognition
should. be given to the fact that much of the progress made since the out-
break of the war, while fostered by war demands and war economy, has been
due to tha foundation of significant discoveries built during the years
precedin- the conflict, Ma.ny of the present-day applications of wood in
military construction, in the fabrication of aircraft and naval craft, and
in oth,-er critical wartime us*es had their roots in the knowledge of design
data, wood characteristics, adhesives, fabrication techniques, and associated
factors arcquired during the past 35 years. while e there are necessarily many
parallels between the wood uses of "'orld ":ars I and II, there are also many
products being employed in the present conflict, such as modified wood and
plastics, which were unkn-own 25 years ago; oth-r products, such as plywood
and laminated wood, have been so improved as to be virtually new*

In more than a few outstandin,- inst-inces, the revived or intensified
interest in wood and the resultant extension of its use have been aided by a
critical shorta,,-e of other es-ential nat-.'rialf, particularly metals. This
has been true in the use of wood in the construction of aircraft, aircraft
han-ars, truck bodies, landing barges, and assault vessels. Currently, the
rrcator availability of metal has sonowhat alleviated the earlier critical
shortage, aud there is an increased tendency in somn quartu-rs to anticipate
an early curt-tilment in the .se of' wood in favor of metal for certain


1
-Presented at the meeting of the New EnClanr.d Section, Society of American
Forest.rs, 3trch 3, 1944, in boston, :'ass,
-Maintained at .Madison, Wis., in cooperation with the University of Wisconsin.
Kimeo, No, R146) -1-







purposes. This attitude is accentuated by metal-minded engineers and manu-
facturers, who have regarded bhe use of wood in some types of construction
as a temporary stopgap, and by the fact that heavy demands have caused wood,
in turn, to be regarded as a critical material. Whether or not wood will be
able to maintain its current position of importance in what are sometimes
considered replacement fields will depend upon the continued development of
new wood products and the improvement of old ones in the face of increased
competition with metals, plastics, and other materials.

The changing demands for wood occasioned by the shift from peacetime
to wartime economy is illustrated in the current requirements for construc-
tion and for packaging. The use of wood for civilian construction, of which
residential and farm construction, maintenance, and repair are outstanding
examples, showed a steady decline from approximately 22-3/I billion board
feet in 1941 to less than 11-1/2 billion board feet in 1943; a further de-
cline is predicted for 1944. At the same time, requirements for military
construction and exports, including lend-lease, rose from 5 billion board
feet in 1941 to more than 12 billion board feet the following year; then,
with the progressive completion of construction of cantonments, warehouses,
hangars, shipyards, and other large-scale military projects in this country,
consumption of wood for this purpose declined to slightly more than 6-1/2
billion feet in 1943. During 1944, a further decline is anticipated, with
an estimated consumption of less than 4 billion feet, although this figure
may be revised sharply upward, as more men go overseas and operations expand
on the fighting fronts, necessitating an increased exportation of lumber to
meet military construction needs in Europe and the Pacific.

The over-all decrease in construction-lumber requirements from 1941
to 1944 has been largely compensated by the mounting demand for the boxes
and orates required to keep war equipment and supplies moving in a steadily
increasing stream to our armed forces and our allies on the fighting fronts
all over the world. The 1941 consumption of lumber for boxes and crates
amounted to 5-1/2 billion board feet, or approximately 15 percent of the
total lumber consumption for that year, and was used chiefly for the
domestic movement of agricultural products and other civilian commodities.
By comparison, the 1943 requirements totaled 16-1/2 billion feet, of which
12-1/2 billion feet were used for direct military needs and almost 2 billion
feet more for indirect military purposes. It is anticipated that a still
greater volume of lumber will be needed to meet packaging requirements during
1944. So great have the current needs for wood boxes and crates become, that
lumber for this purpose is now classified as critical, despite the extensive
use of fiberboard to supplement the demand for container stock. Great im-
provements have been made in container design and construction, as well as
in interior-packing procedures, to insure the safe transportation of material.
Much has also been done in the matter of conserving critical shipping space
and, incidentally, container materials, An estimated reduction of 20 percent
in cubic displacement through the redesign of export containers, means that,
on the average, four ships can now carry the volume of equipment and supplies
which formerly required five.

Perhaps the outstanding example of improved wood utilization is shown
to be in the aircraft fabrication field when a comparison is made of the
"flying crate" of World War I with the Mosquito bomber of today. In contrast

Mimeo, No* R1460 -2-







to the situation in this country, where the use of wood in aircraft, while
cxt.-nsivoe has ber'n largely restricted to training planes and gliders, the
3ritish are r.ported to have 40 dif>,rent types of fighter and trainer planes
using varying opercentares of wood, as 1.lol as meeting 60 percent of their
propeller requirements with wood. '.While favored by thu shortage of critical
metals, tho revived use, of wood in aircraft construction, following a period
during which the wood uirpl:,-e had come to be regarded in many quarters as
practioially oK'olote, is in v.-ry large measure the result of the development
of improved glu.'s arnd plyv.'ood and distinct advances in d&.-ign and fabrication
methods.

Furthr evidence of the adaptability of wood to the rigorous demands
of modern warfare is its use in the construction of naval craft. Solid wood,
laminat,-d stock, and plyv'ood are basic structural compon- nts Ln a number of
ships, including landing vessels, assault craft such a. the famous FT boats,
patrol boats, subchasors, mine layers, mine sw:upers, and auxiliary craft.
Wood is a standard item for the decking of steel-hulled battleships and flight
docks of aircraft carriers; large -iuantities of lumber arc re.4uirud for the
wooden shipways and scaffolding needed in the construction of such enormous
ships. On.: of the outst'ndinL applications of wood in Navy use is in the con-
struction of hangars for coastal-patrol blimps. ".7ood has b.en used extensively
in these structures, the largC.jst of which is 1,000 foet long, 170 feet high
at the crown, and nearly 300 fe ;t widdj at the ase.


"'ood in the Construction Fijld


7ood has been prominent in meeting wartime requirements for military
and essential civilian construction ranging from relatively conventional struc-
tures, such as cantonments, factory buildings, supply depots, and some housing
projects for war workers, to forms unique because of size or new applicationss
of :..ood. In this latter category ar-e such structures azs ji.:antio hangars for
housing :iavy blimps and mobile dry docks for salvafinC or reconditioning war-
ships, as well as certain types of prefabricared buildin,- units designed for
housint- and industrial structures.

T.wo relatively new developments have b. jn lar,_Jly responsible for the
increased adaptability of wood in the heavy-construction field. Th- introduc-
tion of timb.r connectors in this count-.y about 190 ind t>e pionceerinf- use of
laminated arches in 1935 were definite milestoncz in an extension of heavy-
timber constru-ction which has been most helpful in this par Friod and promises
much for the continued expansion in the us-t of wood in t.:e posc.var construction.


i..b'-'r Connectors

The' use, of timber connectors ,.0as devolopcd a:: a m.ans of bolstorin.
an irh,.-rm.nt weakness in conventional timber construction, namely, th.. inability
of the sLool bolts used in joining- wood me.,nbers to dev..lop any large part of
the rntural strength of the v/ood. heo r. latively small cross sections of the
bolts caus the loadG transmitted from one member to Enother to be applied as
shuarin- forces on rustridtod aruBu of wood %!.jtal conn-_otore8 used in


03-.


Mimdo- .0l4Rl'^







conjunction with bolts, distribute the stresses over a much gre,-ittr area of
wood, and thus increase the shear resistance between the wvood m.-mb. rs to insure
joints four or five times as strong as those attained with bolts alone. The
efficiency of timber connectors is well exemplified in the construction of
radio towers. Formerly towers were limited to heights of about 100 feet be-
cause of the weakness of the bolted joints; now they can be erected to heights
of 300 to 400 feoAt. Timber connectors in "fireproofed" timber trusses of
blimp hangars make possible the construction of clear roof spans as long as
237 feet. The resultant increase in efficiency of wood structural members has
extended the .-.pplication of timber to diverse, and often intricate, typos of
construction. Today, timber connectors are making possible the extensive use
of wood in the construction of railroad and highway bridges, shilpwvays, air-
plane hangars, factory buildings and warehouses. Worthy of special mention
are the prefabric,ted, connector-built, 160-foot span trusses in permanent
bridges built to carry the Alcan highway over some of the Alskar rivers.


Laminated Construction

Further impetus to the use of wood in construction has been afforded
by the development of laminated structural units, made by bonding boards, or
relatively small pieces of wood, vith suitable water-resistant glues to form
straight or curved members. Such members, prefabricated at the factory and
assembled on the job, have essentially the same properties as solid wood, but
are no longer restricted in size by the dimensions of logs from which solid
timbers can be cut, or limited to the conventional shapes and curvatures of
such solid units.

Perhaps the chief development in this field is the adaptation of lami-
nated units in the construction of roof arches of varied sizes and shapes
designed to afford wide floor areas unimpeded by supporting columns. These
arches are curved to follow side walls and roof slopes and designed to conform
to the varying concentrations of load. The first building in the United States
successfully employing laminated arch construction was erected in 1935; since
then such units have been widely used for both utilitarian and architectural
purposes in a large variety of structures, to provide clear spans ranging from
25 feet or less to 300 feet or more. Included on the list are gymnasiums,
skating rinks, recreation halls, churches, theaters, factories, warehouses,
hangars, aircraft assembly plants, and similar buildings, both large and small.
The use of laminated arches has also been extended to outside installations,
notably for small-bridge construction. The successful use of these structural
units was based on extensive prewar research on a wide variety of associated
design and construction problems, 'nd on the evolution of the data requisite
to the sound engineering application of the principles involved.

A more distinctly wartime application of this type of construction
is in the use of laminated ship timbers.in the construction of small naval
craft. Counterparts of the glued-wood arch are the curved keels and frame
members used in building ships, as a replacement for the hevwn timbers of large
cross section formerly employed. One of the recent developments has been the
use of straight laminated timbers for the mud sills and head logs of prefabri-
cated wood invasion barges. The successful application of wood in such naval
craft construction was made possible by the development of a new type Clue that


Mimeo. No, R1460







is durable in contact with salt water and sets at a temperature sufficiently
lor- to make practical its use in heavy laminating.

In addition to its use in the form of structural timbers, laminated
wood has extensive application in the fabrication of automobile and truck
bodies, airplane parts (wing beams, struts, and propellers), furniture, gun-
stocks, shoe lasts, shuttle blocks, and many other items.


House Construction

Studies ,oniucted in recent years have enhanced the competitive posi-
tion of wood in the housing field by reducing construction and maintenance
costs anr2, otherwise increasing the serviceability of frame structures. Of
particular significranc? have been investigations of design factors, including
the str..ngth and rigidity of frame walls; determinations of the effectiveness
of vapor h'-rriers in ovcrconing moisture condensation in walls; tests of the
fire-resistanc,- of structural units; and research on painting problems.

One of the outstanding achievements, particularly for low-cost housing,
has been the development of unit, or prefabricated, construction. Such con-
struction had its Inc,' tion sev..-al yaars before the war, but was restricted
in its more favorable application until the introduction of moisture-resistant
plywood. '7ith the onset of the war, the acute need for living accommodations
for war workers in crowded ornur.uniticE so stimulated the demand for low-cost
housing that thousands of prefabricated ply-ood structures have been built in
the Tast several ,years. There is som.? question about the adequacy of some of
this construction, esrecially that which was specifically intended as a
tempor ry housing expedient. In consequence, there is a possibility that
und -sirable results involving serious maintenance may give prefabricated
housing in general an unwarranted poor reputation a&nd thus t.2nd to hinder its
postwar dcv:lopm2nt. It may not be commonly realized that there is a tremendous
diff-rence in quality between temporary war housing and prefabricated construc-
tion adequately designed, and properly maei, for permanent homes.

The fabrication of good quality factory- made plywood housing panels
employs the monocoque or stressed skin principle cormmon in aircraft design,
ceach floor, wall, and roof unit comprising,- a p-.anel of standard unit size having
two plywood faces bonded with water-r,.istant =ynthetic-resin glue to a solid
wood framev'ork. Tnnuluhtion, moisture barriers, wiring and plumbing can be
factory-installed w-ithin the spaoe between the plywood faces, and both exter-
ior and interior finish applied in ad-dvance by rachino methods, thus further
C ir 1 i rlifyini- the final construction at the building site.


Ply.vood


Perhaps the outstanding achievements in wood utilization in recent
yer-rs have been in the uLe of ply:-iood. The critic'. needs of the greatly ex-
r.Ar.ded aircrafPt ,rnd shipbuilding industries resulted in an extensive demand
for rlywood. This, in turn, served as an incentive to research which has been
prl'4icularly fruitful in developing new -nd improved adhesives, rcvolutionarizing

:.,'i.-'o O, R. -R 6 5-







production methods and equipment, evolving better fabrication techniques, and
supplying requisite design data and other essential information. In conse-
quence of these developments, plywood is today meeting the most exacting re-
quirements of warfare, as attested by its use in the construction of the
Mosquito bomber, the torpedo-carrying PT boat, and numerous other structures,
including refrigerated compartments in some of the new Liberty ships.


Adhesives

The advent of synthetic-resin glues., and their steady improvement
during the past few years, have been primarily responsible for bringing ply-
wood to the fore in the war construction program. In the last year or two
these adhesives have appeared in increasing number and with varying proper-
ties and uses. Essentially, the most outstanding of the resin glues cmi'ody
water resistance heretofore unattainable, durability,; strength, and quick-
setting properties. Such glues have wide application, not only for plywood,
but also in the production of laminated arches and other forms of glued con-
struction for exterior as well as interior use. They provide bonds fully as
strong and durable as the wood itself, and impart increased dimensional
stability to the glued structures.

A recent advance in adhesives has been the development of glues for
bonding wood to metal and to plastics, an advance which promises to further
extend the use of wood. When thin metals are superimposed upon plywood, the
resultant product is comparable in certain respects to more expensive thick
metal parts.


Molded Plywood

One of the conspicuous developments in plywood is the production of
curved shapes, or molded plywood. The use of mating dies for the production
of simple curved forms, such as chair backs and drawer fronts, and the steam
bending of flat-pressed plywood are not new. But the development of improved
synthetic-resin adhesives and of new processes, such as bag molding or fluid-
pressure molding, have made possible the rapid and extensive production of
parts having pronounced and compound curvatures which could not satisfactorily
be attained by other available methods. Such so-called molded plywood has
wide application in marine and aircraft uses in the production of half fuse-
lages, small aircraft units, and small boat hulls. Complete airplanes made of
molded units have been built and successfully flown. Molded plywood is also
being used in the manufacture of structural shapes, such as an,les, channels
and even I-beams, as well as plywood tubing of practically any length and
with inside diameters ranging from a fraction of an inch to 2 feet or more.
These tubes have been used for a number of military purposes, such as collap-
sible tent poles and radio antenna masts up to 90 feet tall. The substitution
of molded-plywood tubing for the metal formerly used for radio masts has
resulted in a reduction of as much as 90 percent in the weight of these
structures.




Mimeo. No. R1460 6-


*fc







New Products


Investigations relating to the application of synthetic resins to wood,
egsl:ecially in attempts to control shrinking and swelling and to overcome cer-
tain seasoning difficulties, have led to the development of a group of new
products, sometimes classified under the broad heading of wood plastics.
The basic factor in the development of these products was the discovery that
the treatment of wood with synthetic resins or with urea results in a definite
modification of the material and improvement of certain of its properties.
These changes result from the recognized facts that lignin, the cementing
Lubstanoe which surrounds and binds the cellulose fibers in wood, can be
plasticized by chemical treatment ,nd made to flow, and that bonding the
added chemical groups to the cellulose of the fiber wall and to the interfiber
lignin will alter the physical behavior of the wood.


Resin-impregnated Wfood

When wood is impregnated with an unpolymerized synthetic resin of the
phenolformaldehyde type which diffuses into the cell-wall structure, and is
subsequently heated to cause the resin-forming materials to cure or set, these
additives bond chemically to the fibers in th. wood. The resultant complex of
insoluble resin and wood has a high degree of moisture resistance and, con-
sequently, relative freedom from shrinking and swelling. It also exhibits
definite improvement in certain strength properties, notably hardness and
compression, as well as increased resistance to acids, decay, and fire, and
decreased electrical conductivity. It is, however, adversely affected in one
important strength property, namely, toughness. With plyNood or laminated
wood, the treatment may be applied throughout or only to the exterior or face
ply, thus providing a surface which resists weathering and checking when
exposed in the exterior construction. nhe product of this type developed by
the Forest Products Laboratory has been named impreg.

Plywood or laminated wood of somewhat different character is produced
when the resin-impregnated plies are hot pressed. Since the resin has a
plasticizing effect on the lignin, the treated wood may be compressed under
moderate pressures at the same time that the resin is set, thus acquiring added
density. The extent of densification is dependent upon the force applied in
the press; a pressure of 1,000 pounds per square inch will increase the specific
gravity of practically any species of wood to 1.3 to l.4. The resultant product,
like the uncompressed resin-impregnated material, is highly resistant to shrink-
ing and swelling, as well as resistant to fire and decay. Furthermore, the
densified material is greatly improved in all mechanical properties, except
impact strength (toughness), and has a surface hardness of 60 to 90 &a compared
'ith that of plate glass at 100. It also has a high-gloss finish which, in
effect, permeates the whole structure; surface scratches can te removed merely
by sanding and buffing, and cut surfaces can be brought to a high finish by
similar treatment. In addition, the natural finish is highly resistant to such
organic solvents as alcohol and acetone, w':.hich destroy most applied finishes.
The material can be molded to various shapes during the compressing-heating
treatment; it can also be made with varying density from one part to another.
3U'ch material developed at the Forest Products Laboratory is kown as compreg.


:,irnu,o No, R1460


"7-







Combination materials may be formed in a single hot-pressing opera-
tion, with resin-treated compressed faces bonded to untreated or resin-treated
uncompressed procuredd) cores. The uncured faces become plasticized under the
action of the heat of the press and consequently may be considerably compressed
under relatively low assembly pressures (200-250 pounds per square inch) which
cause only a slight compression of the core. The resultant material thus
attains greatly improved surface hardness and strength with relatively little
increase in weight over uncompressed wood.

Resin-impregnated, compressed material (plywood and laminated wood) is
now being used in the production of such aircraft parts as propellers, radio
antenna masts, chart cases, and bucket seats; and in the manufacture of bear-
ings, gears, rollers, bearing plates, and similar products.


Laminated Paper-base Plastics

A new development, somewhat comparable to that of resin-impregnated,
compressed wood, is the production of a high-tensile-strength plasticlike
paper laminate used experimentally as a substitute for light metals in the
production of stressed aircraft parts, such as wing ribs, wing-tip skins, and
control surfaces. The product is made of thin sheets of special types of paper
impregnated with synthetic resin and compressed together to form sheets or
molded shapes; its properties may be varied to meet special requirements.

Paper laminates treated with phenolic resins have been used for several
years for electrical insulating panels and for other nonstruotural uses that
do not require high strength properties. The new development provides a
plastic with twice the tensile strength of the earlier paper laminates and
equal to aluminum in tension, on a weight basis. Available experimental data
indicate that it can be molded to desired shapes on equipment now used for
making plywood, at similar temperatures and pressures; that it is resistant to
moisture and remains stable at both high and low temperatures; that it is more
resistant to scratching and denting than aluminum; and that it does not
splinter, tear, or flower when pierced by bullets. The characteristic smooth
surface of the plastic eliminates the necessity of special finishes and coat-
ings. The product gives promise for use in water craft ranging from small boats
to parts of cargo vessels, and in the hulls of flying boats. The Laboratory has
named this material papreg.


"Sandwich" Materials

"Sandwich" materials represent a composite construction designed to
use certain properties of the combined materials to best advantage. In such
construction, low-density woods, pulpboard, or other light filler substances
can be surfaced with relatively high density, strong, durable materials, such
as plywood or rosin-impregnated compressed wood. The outstanding current use
of material of this type is in the Mosquito bomber, in which the gluing of ply-
wood faces to a low-density balsa wood core affords a lightweight construction
of considerable -thickness and of relatively high strength and stiffness. The
structural bonding of metal faces to a wood core may also be considered as a
form of sandwich construction.

Mimeo, No. R1460 -8.







Urea-plasticized Wood

Considerable attention is being devoted to a plasticizing process
which was discovered in the course of studies on the use of urea in the chem-
ical seasoning of wood. ".hen green wood is soaked in a solution of urea,
dried at temperatures not exceeding l4o0 F., and heated to about the boiling
point of water, the wood becomes plastic and can be twisted, bent to extreme
curvatures, or otherwise shaped. Upon cooling, the wood again becomes rigid
and retains its new shape. This samre tyre of plasticization can be applied to
sawdust to form solid sheets or panels. The product formed is thermoplastic,
however, and is subject to losing its new shape when reheated to 212 F.
;y this treatment the wood is appreciably darkened.

By adding a resin-forming chemical, such as formaldehyde, to the urea
solution and altering the treatment, a thermosetting product can be formed
that will retain its shape when reheated. Such a product has moisture resist-
ance that is lacking in the thermoplastic form. It is stiffer and consider-
ably harder than normal wood, t'Akes a high polish when buffed, and is bleached
rather than darkened by the treatment# while e this product is still in the
strictly experimetnal stage, it appears to have possibilities in the postwar
development of wood products.


Mi soel lane ous Developments

NTo attempt has been made to cover all of the developments in modified
wood products, or to discuss wood derivatives and new wood-processing methods,
some of which are finding current use while others are still in the experi-
mental stage. Included in the list are heat-stabilized, compressed wood;
lignin-bonded wood plastics, in the form. of molding powders and laminating
sheets; pulp-reinforced plastics; and low-d-nsity resin-tre.ated fiberboards.
Definite advances are being nade also in "fireproofin'" wood, chemical sea-
soning, and electrostatic heating.


Postwar Aspects of Wood Products Utilization


The extent ind rapid pace of current progress in wood research tend
to cloud the picture of postwar utilization of wood products and, :.-et, to
point to the adaptation to peacetime service of .qterials and procer-s dTvel-
ope-I for war. WNartime experience with vwood has brought new recognition of
its versatility as an engineering material. Many of the products involved
will have been tested in the crucible of unusually exacting war requirements,
and aczordinrly should be capable of meeting the most sev-re service r.nseds of
peacetime consumer 7oods in various Varts of the world.

Indications point to an accelerated utilization of wood in postwar
housing, w..%hich will presumably have its inception soon after the removal of
wartir.e restrictions on civilian construction. It has been estimated that
rmor- than 10 million new homus will be needed in the United States in the first
d'-c'?.d, after the war. It is expected that both prefabricated structures and
-orl".:r.tional housing will be important in meeting. the postwar needs. Added


-9-


Mimeo* ::oo R14 60







to the accumulated housing demands in this country will be the requirements
for rehabilitation in Europe and other war-devastated areas.

Heavy demands are anticipated for structural forms of wood, for use in
all types of farm and urban construction and by the transportation, mining,
and communication industries, both in this country and abroad. Timber con-
nectors and laminated arches, beams, and other structural elements are expect-
ed to find wide application, because of the increasing shortage of high-
grade solid wood in requisite sizes.

There is definite expectation that, in many of their applications, as
in making aircraft, furniture, and automobiles, the new steels, white metals,
plastics, and plywoods will be used in combination rather than as replacements
for one another. The satisfactory application of metal-covered plywood and
solid wood, made possible by the development of suitable adhesives, opens an
extensive potential market and presages many applications and unique uses.
These combinations will afford constructions and uses that take advantage of
the best qualities and properties of each material for a given purpose. The
intelligent use of plywood, plastics, and light metals in conjunction will
provide many items definitely superior to those made of one material alone.

The successful adaptation of moisture-resistant plywood to the most
exacting aircraft and marine requirements offers every assurance of its exten-
sive postwar use for utilitarian and decorative purposes. The exhaustive
studies now being made, under the stress of the acute wartime need for plywood
design criteria, are providing data which will be of inestimable value in
promoting the structural application of plywood in the construction of build-
ings, airplanes, boats, and automobiles.

The application of molded plywood appears especially promising, in its
potential extended use for house construction, lightweight furniture, aircraft
parts, small boats and various naval craft parts, automobile and truck bodies,
special piping or tubing, and musical instruments.

The current developments of modified (resin-impregnated) wood, both
the densified form and the uncompressed type, should afford extensive outlets
for wood in the postwar era. The successful performance of the densified
material in war uses indicates its adaptability to consumer needs where out-
standing strength, high durability, resistance to wear and marring, and at-
tractive appearance are important. Suggested outlets include table and counter
tops, trays,and other household articles for which cigaretteproof, alcohol-
proof, and waterproof surfaces are an advantage; fine furniture, luggage, and
novelties; paneling and other architectural details; ski runners and other
sporting goods; ship decking; face plies in the skins of aircraft plywood and
in shells of boats, pontoons,and like structures requiring water resistance;
and industrial ventilating fans and similar articles which require not only
strength and stability, but also resistance to corrosive atmospheres. Full
attainment of many of these uses will be dependent upon the ability of the
producers of densified wood products to meet the competitive price of other
materials; while relatively expensive at present, quantity production of resin-
impregnated compressed wood products may be expected to result in appreciably
lowered costs.


MimeoM NI R1460


*10-




UNtVERStTY OF Ft ORIDA
'1011H IN I!IH III lii IN 1Hi1OH I11I 1I1111
3 1262 08925 4014 ;
The uncompressed resin-impregnated wood wii. prooaoDLy aiina appsLzio.:-. ":
tion, especially as production costs are lowered, for items in which relatitw l:
freedom from shrinking and swelling, and durability are important requisites, !'.
such as parts of' aircraft, boats, and vehicles, exterior doors, electric
cabinets, precision instruments, and sporting goods. f

The future use of wood plastics, in competition with plastics from
othxr sources, will be determined by relative costs, serviceability, and
Renoral consumer appeal. Their performance in war material and the production
experience rained by war contractors who may use these plastics in quantity
will have a significant bearing on the postwar application of the wood
doer ivative s.

The application of laminated pap.-r plastics to consumer needs offers i
much promise, especially w.'hen decorative treatments are given to this durable,
strong, and dimensionally stable material.

The quantity of wood used for shipping containers is unquestionably
destined to be diminished in the postwar era, when improved handling and less
adverse shipping and storing conditions and a marked contraction in the export
movement of supplies bring a renewed emphasis on relatively low-cost, light-
wei;ht fiberboard. Solid wood, veneer, and plywood, however, may still be
expected to fill an important need in the riil, truck, and water movement of
certain agricultural products and of heavy and fragile consumer goods. They
also have possibilities in the design of lightvweight, compact containers for
air transportation, although the low tare weight and relative cost of improved
fiberboards will be a distinct competitive disadvantage for wood. Attention
is beinr devoted to the combination of wood and fiberboard as a means of in-
corporating the advantages of both materials in shipping containers.

A definite increase in the over-all us-3 of wood is predicted for the
years immediately following the war. This nay involve an extension of use in I
housir.n Rnd general construction, a reduction in aircraft and containers, and I
the invasion of new fields with improved and novel products.

In the inevitable postwar competition of improved steels, light metals
plahtios, ceramics, and olass, the ability of wood rind wood products to hold
the Rains of the past several years will be dependent upon the unabated researoSb
efforts of the chemist, engineer, and wood technologist, and upon the aggrei-
slve support of the wood industries and associated a1:encies in exploiting bthe
ad7inced techniques and pushing the conventional, improved, and new products in
both established nd r.ew fields of use. Unlike the wartime era, the postwar
developFmcrit of1 markets for wood products will have to be made without benefit
of shorta&es itn competing materials; the utilization of wood -roducts will, of i
necessity, 19 on their ow. merits and must be econom:iQally sound, .









t/imeo, Nto, Rll.'-C -1i- :"1.


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