Conditioning practice for kiln-dried and air-dried aircraft stock

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Material Information

Title:
Conditioning practice for kiln-dried and air-dried aircraft stock
Physical Description:
Book
Creator:
Forest Products Laboratory (U.S.)
University of Wisconsin
Publisher:
U.S. Dept. of Agriculture, Forest Service, Forest Products Laboratory ( Madison, Wis )
Publication Date:

Record Information

Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 29306361
oclc - 755606800
System ID:
AA00020557:00001

Full Text
U)NIATIC~NINC.7 ANU ST(AP~INC ()f
AIPCPAIFT STOCK~
Pcviscd Haty 1943

NfENT OrAe
1TIlS ]PUP.OIPT IS ONLt Of A SIPIES ISSIEV
TO All THEf NATION'S WAIP PIP(*IAM
No. 1370
UNITED STATES DEPARTMENT OF AGRICULTURE
FOREST SERVICE
FOREST PRODUCTS LABORATORY
Madison, Wisconsin
to Cooperation with the University of Wisconsin




!-rearin Air-dried l c for -q- lifacture
TUuI ly uti rred &tc s t in n at isfcto-.ryc cndI tion ror ai-r ftue
ti-c ,i'ecc~rprcdre is to at ce fi r in c q fo)r -fia r.n P.:
rei-.fc eardeni.n Ftr-,,! es. f il in is not vaial andif sF-
fiin triesprce is avtilal n m or re-os heated, ro r, sig l
rra~~c3 ~ stre ir- ri-e lur-iber in suhroor~ unti-l S stre p o
Be~ ~ F'r s h'v e any 7-c i -inr e viardein 7tese usbe r r
by~~~~~~~~~k I cdtluntrt'eti kln o r in te stora! e roo fterltv
enno -a ae fco cise imlrl A erx.cet t c c-t ror ran 7N i re
rnd~ It" ~ r. -o ac riioe ma hnb ue iei kl r
lrc--:in ue s~ ',_il be- -.scrved : roc: ri r
(,xi g--i le fo-undtils suhbe esie to r p~it circlin beOw
1e hel~stlyr o f Iabe r- r ol be h i:,n 7 aoeteI r.
* ~ i 'ls s~uube f fe t 'I t, et o' r t,.a ~ p .7e t us~ jl ,and
~ ethi 6C fetwd.kS.ul be lc ed r. 1ic cesw
A i -t ver i6/4 rac tuk Fo hce era ofrntr e
2ticrs 1'4i b evk~l sl~re -i. ac~r~ nott excrc2fe ~
t) ocir~nin~ j: i j-t~~ I nt ear sor th. : >er
Sffura ot 1f h r '7. ci f t 7-e cor.4Ir ol ist~r otn m b
___ t_ r, I id y an osur r~~ os- r~ergt t".e
mia recit ci roJ otY c n i' sL01 c orb~ to
~eur~ ~ drIr~crmeaueai uiiycniin ycnrligol
I>,Cter era ar. ~rconut ior n tratmntsI wverst a c7-t -
5~r~x :nyv roi 1

iir~~eo. .3 P7 0 evs




Storage
Aircraft lumber should be dried to meet moif-tdroc Cnn nt an ,eLar, denJ i
specific.- tions, and subsequ,- nt str -e sho, 1 bo relied upo n T-.r('y to
obtain additional benefits in the for7- of moro nearly unifu~rm t1rosverse
moisture distribution and further relief of caneh,)rldeinfgr stre.;,e3, Ir' r
kiln-dried stock at least two weeks storage is desir. ble for this purpos ,
but to maintain t',-e stock In satisfactory condition v-at'.1 used in thep Sihop,
the storage conditions should be controlled withi .. the moistu're-cor-tent
range specifieA. Tle stock then may be either left on stickers or solid
piled.
Stock stored under uncontrolled conditions may becOTTo uiisatisfac ory re, arjI-
less of the mtetihod of piling, because a lonjitudirnal moisturee 7radn rt may
develop in a solid pile and a v-enelral -"oisture piolv-up may eoc --,r in an open
p ile.
Stora-,e of all material before manufacture should be under con itionis tLut
Will deliver the stock sound, free from, seasoning; defects, and a-t suitabl-,
moisture content. In order to reduce moist-ure chao or to skecujre .,ood a
given moisture content, it may be necessary to equiip the stortwre shed, r
factory, with humidity-control equiipntn1 so th.-al t *i ran -e r,,f non -ture
change -nay be controlled. The humi dity sho,,ld b-1 s( controlled t' ^at -11-e
moisture content of stocks other thtn -roreller mterial cannot fall belo ,
8 percent or rise above 12 percent. "ro,)eller stoc- shl-.u b c stored' und-er
conditions that maintain the nols4-recotentbetween~ i nercent.
Effect of Storarre on D11ef-ects
Stock that has been dr-Lel to th!-e acceotable moisture content, I/ $etciy
may be held for -.-n indefinite neriod without deterioration fro -L sesisonlinrij
defects, such as chleckin--. oneycomibjir-, stain, andi deca*y. Certal -: icods
are subject to insect attack even ai-ter dryi.,,F. 2.e -Alyctl ,s pow;der-,pult
beetle attacks especially the seasoned sapwnod of hickory, ash, and oak,
and it also damages ot'ier hardwoocis sic~h ,,s walnut. ma,,.le, cherry, el! ,,
yellovipcplar, and sycamore. Ot.h-er po-,:,er-jpcst be,.tles attack bot ~rwo
and sapwood, and both* hardwoocis and, softwoois. St o r e(I stock tnat is s.-,bject
to insect attack should be moved in roittion, so that none of it -.-ill remain
exposed to infestation for an excessively lon-z time. Suc ) stook s".o 1d be
examined regularly and carefully, and 1!rer-infeted. stock shoul' be either
heat-sterilized or destroyed. Ini-estation of ac Jacent st ock is .:,erely a
matter of time ifll proper preventive mp~asures ar( not obs-1-ved. Th ,e larv~ae
of the Lyctus beetles bore inwar(-1 -ivin,,- little or no early i Adication of
their presence and thus makinp, pro-_ .,- recognition of infestation hi hly
difficult. Borers eat holes from 1/16 to 1/4 inch in diam~eter 'and leave
wood Powder in them. T.hen a hole penetrates an exterior surface, the n-~
can be -arred out, "adly tunneled i-io:! can easily be broklen.

!"imeo N~o. 1370 (Revised)




Figue --Relation of the equilibrium moisture content of roo,, to the
relative humidity of the surroundin- vt7,csrh ere a he
toei-nerptures.




30-- L ~
~25- -- - _- - _- -
20 ___ __
- _ _ -- _ _ p
00,
_~~~0 __
0 0 /0 20 5
0/ 0 045060 70 80 90 100
ZM6~55q4r R'EZATI VE HAMPITY 11Y tATMOJP/EA'[ (PFIF CEAIT)




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