AGRICULTURE ROO M
WHAT CAN ICE DONL IC MAISI PAINT
MAI~1Tf~ANCL MOPE SUCCESSFU L
UNITED STATES DEPARTMENT OF AGRICULTUR E
,FOREST SERVIC E
- PRODUCTS
LABORATOR Y
Madison, Wisconsi n
LL
Lr
In Cooperation with the University of Wisconsin
March 1938
SCHOOL OF FORESTP 4'.
OREGON STATE GOLLEG r
CORVALUS, OREGON
WHAT CAN BE DONE TO MANE PAINT MAINTENANCE MORE SUCCESSFUI r
.By F . I . MOUE, Senior DhoMis t
s
The success of wood as an exterior ao ;ping far housep .epend s
upon the success with which a coating of paint
be' maAht.&I.
, og th*
wood. In general the wood is put in piaee when the house i 1 M and
remains there as long as the house is nee4ed whether it is*
.inte o r
not, but on houses of prideful oeeupancy the appeatatte Of . athe
ten
wood is rarely desired and decoration with paint is
e.
w`
The life of paint, however, is limited to a few years so
. 'fie coat
ing must be maintained by applying more paint from tie tb t
@A ,Pr op
five to six times as much house paint is required for rmnacuk SW'
coatings as is consumed in the initial painting of new waoADMEMb
to
Those who make and sell paint are in the habit of th '
all these paint jobs as separate transactions independent of ti
sit
that went before or are to come after them . The house owner, 100
sure, buys his paint jobs one at a time, but his real intiappaiP•
41
r .
coating satisfactorily maintained over a long period of the misunderstanding and disagreement about paint c_oWs _
'
-.
appreciate that paint maintenance is a long term mA44lig !IMO, up of a
succession of paint jobs that must fit together into a bri ious wholes ,
+
Paint maintenance is successful
It des up ttm OIN; ovine
reasonable expectations both as to continu © oaf Ike elvolsem,
,tivel
effect and as to cost, Owners' expectations, however, vary wiaeli,t.
Some, following tradition of long standing, expect to repaint no r
often than intervals of ei, l t or tan years . @til, s,
"arty ,
oeg
standards may be more ex
rngw are willing to p .
aV
years . A negligible few m i d be willing to paint still m*pe ofti
Practically no one, h1ev',. expects ever to be put to Vile extra Op o
pense of completely regamie
an old coating before a iAsg SON
offlT
.
and any maintenance pi agVam t'rl : t leads to su 1 even#i a4ty
regarded as unsuccessful . All of the above expectat .
s. o-f
owners can be satisfied with good house paints now on the market, bu t
no one kind of paint is capable of satisfying all of them . It is idle ,
therefore, to attempt to discuss good paint in general terms -- we mus t
discuss it with reference to the kind of maintenance program for which
it is suitable ,
m6
V'i
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'resented before' trha
l G
Q O+a ,ef the Southwest, men l s Association at Kansas City, Mo ., Jan . 27, 1938 .
.B.ll9S
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What proportion of paint maintenance programs proves unsuccessful no one knows . That the proportion is unduly high, however, can
scarcely be denied . The Lumber Products Better Paint Campaign wa s
organized because the seriousness of paint failures is generally rec ognized by lumbermen . The writer's research is constantly being interrupted by calls to inspect paint jobs that have gone bad, more than 17 0
cases having been considered by him in 1937 .
During the past fiftee n
years he has been consulted about unsatisfactory paint conditions o n
several percent of the frame dwellings in his home city . That painting
has become unreliable enough to impair lumber markets was shown by a
recent survey of new building by the Forest Products Laboratory in whic h
nearly half of the new dwellings of medium and low price groups in
twenty--five cities were being covered with materials that will not b e
painted. There can be little doubt that this sharp change in pas t
practice has been stimulated at least in part by the public's discouragement with paint maintenance . An examination of the causes o f
unsatisfactory paint maintenance and possible ways of correcting th e
situation is therefore urgent .
In the public mind poor paint and poor lumber are usuall y
held responsible for unsuccessful paint maintenance . This opinion i s
readily understandable, but is not entirely just to either paint o r
lumber . The major causes of difficulty are much more intricate, Th e
great majority of paint complaints that come to the writer's attentio n
involve the best woods for painting and the best grades of paint .
Moreover the writer's experimental work has shown that even the poores t
woods for painting can be kept well painted at reasonable cost, an d
paints of comparatively low grade can be used successfully, though no t
necessarily economically, if the nature of the materials is understoo d
and the paint maintenance guided accordingly .
Lumber in Relation to Paint Maintenanc e
It is true, of course, that some kinds of wood hold pain t
better than others and that in any species high grade lumber is bette r
than low grade . A classification of lumbar from the point of view o f
painting was published by the Forest Products Laboratory some years ago .
Building practices in most parts of the country for a very long tim e
have made use of lumber pretty much in accordance with this classification ; that is, for exterior woodwork of buildings on which good pain t
maintenance is likely to be considered important it has long bee n
customary to use the higher grades of tht)se species that naturally hol d
paint well . The species with wide bands of summerwood on which pain t
tends to fail relatively early are used for the most part on les s
i
important buildings or buildings of strictly utilitarian purpose . Li
the Southwest, however, the heavier softwoods are more widely used on th e
exteriors of dwellings than in most parts of the country because of the
ready availability of such woods there .
R119S
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Maintenance of paint on the heavier softwoods could be very
r
J
I
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greatly improved by the more general use of aluminum priming paint fos
the first paint job . For this purpose aluminum priming paint
IMih '
be confused with the many other special primers that have appeared on ' the market in recent years, which are designed for an entirely differen t
purpose . Unfortunately aluminum primer has not received the acceptanc e
it deserves . Paint manufacturers oppose it because they feel that the y
cannot readily present it as an exclusive proprietary product . When
they sell it at all they are inclined to furnish a vehicle that they are, .
making primarily for some other purpose, one intended for aluminum paint ,`'• "
on metal, or one with some fancy variation of their own rather than the
.
simple kettle bodied oil vehicle that is best, Lumbermen producing t 1
woods that would be benefited by aluminum priming hesitate to push i
tbecaushydontlikeamhteirwodsnpen
cautios
painting that are not so necessary on other woods . The road to improve ment in paint maintenance on the woods in question, howeVOOw .0 gain] •
marked and can be followed by those who wish to do so .
1 1
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1
The Cure for Poor Pain t
Although the writer has rarely encountered really inferio r
paints in the cases of paint complaints he has examined, he is tol d
repeatedly by paint manufacturers and others that much inferior pain t
is made and sold. The Federal Trade Commission and Better Busines s
Bureaus take action against notoriously bad paint from time to time ,
but they can deal only with paints so inferior in quality that thei r
sale is a downright fraud . Paints that are merely inferior in quality ,
but not clearly fraudulent can be dealt with effectively only by clearl y
defining good paint . When the regional lumber manufacturers were pre paring their pamphlets on painting instructions for insertion in bundle s
of bevel siding they found that there is only one kind of good pain t
defined in such a way that it can be discussed in general recommenda tions . That paint is pure white lead, commonly known as lead and oil .
Other kinds of good paint are identified for sale by trade brand only ,
vary widely in composition, but conform to no standards by means o f
which the various kinds and grades can be recognized by the users .
a
The Forest Products Laboratory has recently shown that it i s
perfectly practicable to define good paints of all kinds in such a wa y
that they can be set apart from inferior paints . In fact, it is tech nically feasible to classify paints in a logical manner . The propose d
1gradingn rules, though technical in nature, are much simpler than th e
various grading rules for lumber . While some technologists of th e
paint industry recognize the desirability of classifying paints th e
paint industry as a whole is opposed to it . Since the idea is a new
one originating outside of the industry, it is by no means surprisin g
that it should be regarded with suspicion, especially since its primar y
purpose is to provide a clearer basis of mutual understanding of th e
composition of the product between manufacturer and user in so far a s
R1198
-3-
e
composition affects the correct use of the product in practic
there is a better way of accomplishing the latter objective 11
be hoped that someone will soon propose its,
,
.si.fs it
The Forest Products Laboratory's proposed syst
did+
ing house paints was published in detail in the Am'ericAr -PIkSt
1
issues of October 11 and 18, 1937 . Briefly, paints are sepal i
types according to the nature of their opaque white pigments and th e
proportions of the two kinds of chemically active white pigments ,
namely, white lead and zinc oxide . Each type is then marked off int o
divisions according to the content of total pigments, opaque pigments ,
and nonvolatile matter (pigments plus drying oils) . Where paints contain vehicles other than the customary unbodied *'Ong 0040,,
+
linseed oil, additional classification is provi
. Aft SO
2414 s
opinion the proposed system of classification a
awVMO'pAtaktir
essentially the same way that any well informed paint *0MMMAWMt
would evaluate them but, inasmuch as the various types 446 44wolaW
as differing from one another witka t iaferrimg t
ictv
one is inherently better than another, it does not lend wu port
,
one school of thought about house paints at the expense 6-Ff'contra r,
opinions. Each may chao,sie whatswea type of paint he ptWi;A s amA x
those he dislikes.
The proposed classification assumes that the
415e
administered by the appropriate trade association, just as
_
ing is administered by the regional lumber manufacturer's asI
A commercial paint would then be identified *ors a bs~
12
facturer's trade brand, which would remain his sea'
for quality of the product, and by the association's symha%s of t
and division . These symbols would be simple enough to be eacplai r
laymen, in contrast to the complicated formula labw% tin
men e$gggOis .
on many paints in conformity with the laws of same staff . il
symbol of type and division might read : "This paint is of T(titanium, lead, zinc) type with medium content of white l e
medium content of zinc oxide, division M, as classified by ta';e
.Association," With paints so classified there would be no g + b
difficulty in telling the public the difference between good paint s
and inferior paints . The problem of cheap paint, therefore, can b e
dealt with effectively just as soon as we really wish to do so .
Pees
L
"Moisture" Failures and Their Cur e
Access of moisture behind painted woodwork is the cause o f
one large class of early paint failures . The moisture may *get in throug h
carelessly designed or erected joints in the construction, or by conden sation of moisture laden air from inside of the house when it comes i n
contact with the cold back surfaces of the exterior woodwork . Troubl e
from condensation has probably increased materially in recent years
&1198
I
1.
ti
makes the back
latioxn
se o
r
at escape from ' "fir ■
tting
~ar race s• it - ,se~ roodvror
a
•
idification in
tins idol Mlllf *MUM > provit ' iil4r NWT- MI
troublesome
')
kind.
64Wpm
IMftuni heatin1
ern
areas
where
~
in
more
s•
--e
1iarts cr
ks
d
without
eathing
an
es cassia 'th drip
,
gas burners, confed with inadegui
riMted
me
times occurs a s
Is the sidewalls or 06014
'
e
combustion
of gas& ' .
• salt of tount of nwaldlWit
11
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prevented by keep-4
be accomplished. - '~-'
1PIPPigde of the studs
e s already erected two
lls and
on the
er which
-1r b
WSW liliwASiSi maims an el
om open
>fi.sture
,101applie4
e
S 34
softW
11i4quat
Ilp
MINIM
ofi
gas b
Much
house*
su*
ccook.
1ng, laundry work ,
=its,
f+,- Ville ' undoubtedly vary in
p
~abit~ IMF
~levaporate,
1 $nouni~ Wi
amount
opening
vrin.dous
n the
t
lie
re
m
a* Bs Otiallimo
rs and
e
.
th
i
10
t
windows'
and
adjustmen
Imm
atr tab
as;
MOIJI Ike condensation is re-evaporated .
ssary, whether or not th e
RRorthfOr
'
w$am ours
pp
+
+I o sa
cp +
vri'BYi i!; limit InO douse T
Wg cow INdpAnniFli,
NW=
ta -
-
,and condensairtualapeLy tae
.41Y alilk
r new houses and
tion a
omir$ feneral
¶e s
ctive
moans
of keepin g
son* RIP
a a] dy a
i~ _
InPi a@Plmlk
undertaking
of
the Men* &►
mom Own
VIP E,finatia
the
hous
e
educai
ned wii)b
WI louses &nd
ing tha i
owners
punds
.t thee§ II
in time
iii
be elimi
1
he Cure for Miff,
Icesnigh
des from fad technic in applyat&
Wise from t painter's very huma n
ing pains
ilhat contar4i
Aesire t~ 410 tl&D >Irk wit'Tie s', WINO Oa expensive materia l
. aOrt'Go '
manufa
thaw es Make his paints with
i. C r y I"'
r_. 1
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the smallest practicable proportions of the more expensive ingredients .
In most cases in which the bounds of safety are overstepped the painte r
was not intentionally dishonest, he was merely mistaken in his judgment
or unfamiliar with the limitations of the material with which he was working . . It should be remembered that the painter's judgment is necessarily
based on insufficient information because, except in the case of lead
and oil= he does not have practical knowledge of the composition of th e
paint he is using and there are no generally accepted standards of cor- '
rect application . Commercial paints differ in composition far too widely
to conform to any general standards of application, and since they are
not recognized by classes each paint presents a separate problem i n
application. Often the painter is asked to apply a paint that came on ,
the market long after he learned his craft and differs seriously as
respects application from anything he has been trained to use correctly ,
To be sure directions for application are usually printed o n
the label on paint containers . The painter is often chided for payin g
little attention to such directions, but when manufacturers' direction s
are studied carefully in relation to the composition of their product s
it becomes clear at once that manufacturers' ideas of correct applica tion are just as divergent and illogical as painters' practices .
Since directions usually are most explicit about the extent to which
the paint should be thinned the conflicting state of opinion about
application can be illustrated by considering manufacturers' direction s
for thinning.
Table 1, which is condensed from a much larger table of data ,
shows the composition of 18 semipaste paints on the market in relatio n
to the makers' instructions for thinning to make finish-coat pain t
and the composition of the paints when so thinned . The paints ar e
arranged in the table in order of their content of total pigment b y
volume, which decreases from 0 .58 to 0 .30 gallon in 1 gallon of semi paste . The content of opaque pigments, calculated by the methods
described in the Forest Products Laboratory's system of classification ,
ranges from 0 .52 to 0 .18 gallon per gallon of semipaste . Yet wit h
negligible exceptions the thinning directions call for the additio n
of a gallon or more of liquid to a gallon of semipaste . This proportion is obviously determined less from consideration of the best wa y
to mix these paints than from the fact that the accepted proportions
for mixing lead and oil, namely 3 gallons of oil and 1/2 to 1 pint of
drier per 100 pounds of paste lead, is very closely gallon for gallon .
That the thinning directions are not guided by any logical relation t o
the composition of the semipastes is shown by the very wide variation s
in the composition of the resulting paints after thinning .
Table 2 shows that for prepared paints also there is a lack o f
logical relation between composition of the paint and directions for thin ning. In Table 2 after the composition of the paint there are given th e
directions for thinning the first, second, and third coats in paintin g
new exterior woodwork of the kinds of wood the paint manufacturer con siders best for painting . Sometimes the directions call for v.ariatioss
R1198
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ariation in composition of semipaste paints on the market, manufacturers' directions for thinning them for finish coat, an d
characteristics of the paints when so thinned
mmhm 6
;
IDmposition of semipaste No-int
: Liquids to be added to : Characteristics o f
:1 g-ol,. of semis 00401
sing paint
tifi<- l
~~
--cation :
.I,'l onn
a.:
l :Opaque . Xvn- : Linseed :
: Total
••
:-pi:amlOiit :pigmea;t :v®' 1 t' :,e': i5olt3. : . oil : 'z
!tpigmen,r,
..volatil e
20
3Z . .
Lead . &:
oil . :
38
...:
19. . . . :
27 . . . . :
18 . . . . :
23 . . . . :
3
4. . . . :
0 .58 . 0,34
.53 1 . 27
0.97
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.52
5
.50126,
.50
. 145
.44
.44
)43
.
.
4
Z
.28
:
.
.25
.3 8
.34
.2 6
.4.3
13 . . . . :
.42
.
.37
.3 5
39 . . . . :
41
.39
:
:
.27
.36
.37
.35
.30
:
:
:
.37
.31
.26
2+ . . . :
12
36. . ., :
.41
:
.
: 1,0
. 0t
s9
.1 8
1 .05 1,00
: 1.03 : 1.00
. 1 .0 : 1,00
1.00
•
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•
▪
t
y
0
.13
0
.05
.03
: 1 0.0 1,00 0
. 1.0
1 .00
. 0
,0
1 .00
0
>r,: 0 : 1 .00
; 1 0;25 1 .25
41
. 1,8 .5 . 1.20
.,, a7 . 1 .07
AO)
.90
: 1 .0
: .87
1,,0
.95
. g.7
, 97
. ~9
7
46
gal . of s.
•
:
1 .00
r1 . 1.10
.75 • .75
:
:
•
0
0
. 0
0
. 0
0
.05
.
.
:
.
:
.12
.75
.87
:
.17 :
:maker gives no chrections :
• • 87 :
: 1,o4 :
a_
Este ?TOE
Wiest Nos* 4-Agg. ga
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Percent
29417, 0
260
13 . 5
98 . 5
85.0
2 56 . 25 .3
25 4.1; z
25 ;0
93 . 3
94. 6
93 . 5
25 .0 :
22 4 5 ;
224
2200
4
19 0 1 .
12 .5 98 . 5
19 .0 . 84. 5
17 .0 : 86 . o
13 .0 : 93, 0
19 .1 : 92, 1
18
$ 16.4 : 96 . o
20.3
16 .9 : 97. 0
20.,E t
9 .0 : 95, 0
19 .5 t 12.9 . 95. 8
22 .,3 t 20.6 . 94. 5
t
:
19.8 ! 19 .8 : 93 . 6
17.2 : 15,2 : 86, 3
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ON
in thinning the first coat for different woods, in which case it i s
seldom possible to recognize any reasonable connection b:etw j t' a
properties of the woods and the variations in thinning speci Fie4e As
a matter of fact, the names by which the woods are designated ofte n
are not the names under which they are sold in commerce ,
An old rule of painting held that the undercoat (the secon d
coat in three-coat work) should always be mixed with more pigment in
proportion to oil than the finish coat . This rule is still recognize d
in directions for thinning lead and oil and many semipaste paints . I t
does not fit in, however, with the conception of prepared paint a s
ready for application without further thinning . C'ans:egiently it wa s
formerly customary to direct that the paint be thinned o l:y with turpentine for second coat so that the undercoat would contain at leas t
no less pigment when dry than the finish coat . Tight of the'twet y
paints of Table 2 break with this custom and depart still fag t * fx~p~n
the old rule of craftsmanship by directing that oil be added to ;We e
paint for second coat . Of these eight only three call for ad it oA . e.f
oil to the finish coat also So that five of them definite-1 .y. Nt of tx e
painter to violatea rule of craftsmanship to which the elder pa eke0t.
were trained .
It is curious that the instructions for eight of the- tDaut y
paints in Table 2 direct that the paint be thinne4 for all t ;ee
one of them calling for addition of as much as half a gallon of oil per
gallon of paint for finish coat . Such a paint ought not to be ca led' a
prepared paint, but rather a semiprepared paint . As put up in the ean
the paint in question is of very respectable quality, "a .t when tOrAe1:
as directed for finish coat its content of total pigment drops to,16s 7
percent, and its content of opaque pigment to 14 .0 percent, figures ge t
at all in accord with modern conceptions of high quality in house paid .,
Bad technic of application can be cured only by education i n
correct technic . We cannot teach painters to read and follow directlons ,
however, until the directions are reasonable and are agreed upon b y
those to whom painters must look for instruction . Where the teacher s
contradict one another the pupils, being human, hold the teachers '
opinions lightly and follow their own judgment, inevitably making many
mistakes in so doing . It is the writer's opinion that the presen t
irrationality in directions for applying paint arises less from lac k
of technical knowledge than from commercial considerations of pric e
competition . Manufacturers' directions are written too much with a
view to convincing the painter that the paint will "go fartherw than
competitive paints and too little with the idea in ,mind of mating sur e
that the paint will give the best possible performance .
If paints were properly classified according to composition ,
paint technologists probably would find no great difficulty in agreeing upon sound instructions for applying each of the classes of paint ,
provided that they were permitted to do so solely from the point of vie w
of performance . With such agreement on standards of correct applicatio n
R119S
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a campaign of education far pa.• nt•ers becomes practicable, but unAl i
there are such standards there is no way of giving p:a,irit e is adequantre
instruction.
The cure for bad technic of application, therefore,
in
classification of paints by some such method as that proposed by t4 e
forest Products Laboratory, followed by agreement upon reasana14e IR O
structions for applying each class of paint, and then by united an d
vigorous insistence that painters learn and follow the accepted s :tara, r
of app lbeaaM
e
The Oure for Mistakes in Paint Maintenanc e
In the writer's experience more complaints abort paint gobs ar e
caused by incorrect programs of maintenance than by poor lumber, poo r
paint, bad application, or moisture . Neither the paint maruwfaestmirexr how '
the painter, as a rule, has much control over maintenance because tb :e
house owner generally decides when painting shall be done, how mpi& wGi k
he is willing to pay for, and often what brand of paint shall be lased .
Efforts to attain more successful paint maintenance, therefore,-mvw, i
take into account the necessity of teaching house owners how to spac e
jobs correctly and how to choose the right kinds of paints for thei r
purposes .
Many house owners have no definite plan for spacing paint 4dh s
and merely wait until the old coating goes to pieces before trying tv
renew it . In this group many have no intention of painting more af't' e
than every eight or ten years . Since we have no white paints that ea u
be relied upon to remain durable for such long periods, those who follo w
such programs are more interested in the ability of the paint to stif d
neglect well than they are in its durability . They want a soft type O f
paint that breaks up slowly by crumbling so that it does not look
G
keuipt during the period of neglect and after neglect can be safely re painted without expensive removal of the old coating. Pure white head
paint, if used exclusively, will behave in this way, and is largel y
responsible for the fact that so many owners are accustomed to main' tenance programs involving long periods of neglect ,
Most of the newer paints, however, are made to provide gueater
durability and superior appearance, which can be provided only by making
harder paints that break up finally by cracking, curling, and flaking ,
and therefore cannot be neglected safely . Of course, practically al l
paints are advertised as wearing awa7 slowly by chalking, leaving a
fine surface for repainting, and avoiding the defects of cooing an d
scaling, but such claims are made on the assumption that repaint : . g wil l
be done before the end of the period of durability and before neglec t
begins ; they do not mean that the paint is suitable for those who e' piet•t
to let their coatings go through periods of neglect .
R1198
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SCHOOL OF FORESTR Y
(a: irr
OREGON S
.CORWIDS, ORLO N
a
There are two Ways of successfully linking' together the maim ..
tenan•ce program and the kind of paint Per those with unduly lon g
intervals between paiDtiag One way is to cm:mince the house owne r
that it will be worth his while to d bangs his program to pe►vanit hi m
to use paints of harder type satisfactorily . The other way is to
'himtekndofpaith t
will serve Satisfactorily In the progA
which he is accustomed, . To persuade him to bey a pant unsuited to th e
program he intends to follow, however, is simply too a1d oae more to t,hO
number of those who are dissatisfied with painted weer :Work.
large proportion of paint complaints that come to th e
write r t s attention occur on houses that have been painted at reasonable)
intervals with good paints well applied on woodwork that remslhS dr y
and yet the pa4nik i
toe anon and often in as manner not -g ranter .
istie of The MORRlt_ labert&e ee the paint last used. In all
iso s lAsf,,
however, two or more pants of distinctly diff r t composition hav e
been used for successive paint jobs or successive errs inn tit? sam e
paint job . Some of the combinations show up re ieertl :y in differen t
complaints . Some well known combinations free
ivy oc-curriia, Sri complaints are white paints over yellow ochre primer or paint, a►t any'
house paint over clear varnish, and whine pa-lots e
full -Gem PaIdpoeva.
like deep red, brown, green, or black . Unfortunately technical exposur e
tests in the past have been confined chiefly to initial paint jobs or roe
painting with the same kind of paint, but some past records of tests it volving combinations of paints differing in type have been discovered ,
the outcome of wiz * reveals the same abnormalities of behavior foun d
when these combinations of paints are seen on houses .
to
etiaence Sat good paints are not all compatible with on e
?*_►w$!er 11 now conclusive, but there is much differe=iee of opinion abou t
the seriousness of the problem. Some hold that incompatibility occuAp
e
only in a few extreme cases such as those named in the preceding past
graph . The writer believes, on the basis of both Observations of homer
and of technical exposure tests, that the principle of ie rapatibili'r7
i very much more far reaching . Combinations of white paints, differing
content of zinc oxide, for example, have been observed t o
deteriox
more rapidly and in a less satisfactory manner than corre sponding coats made up entj ely of either one of the pa-i t .s separately .
A great deal of retearah Will be necessary to establish alga. of the
ramifications of the principle of compatibility, but when it has bee n
done many of the present ary teries of house paint maintenance will b e
cleared up . A large proportion of the Forest Products Laboratory' s
research an painting is now di e- t-ed toward this prebJeem .
Certainly those combinations of paints that have frequently led t o
difficulty should be avoided . At the present time the only whit e
paint that is used consistently by large numbers of house owners i s
pure white lead because it is the only paint recognized by type as wel l
as by manufacturer's brand . In the writer's opinion the high regard i n
which white lead paint is held by so many good painters, and aLat . .u.sers
lead
is due larzeiy to t'n3' s consistency in its us
atu'+ly
d
mintsit*
tends it o
0MALMR
an ahm+l
,ne r, ,
that it iir _
ject . %Me re=
bilit, a
pain s as are pates +E' othe r
4POO401614-Or
kinds
'art
_,O 'tMO froglMem4 vi 'Fad
, therefore ,
lies in a classi.fic et-i.on of pa ntt .M t3 wu4i.l aevbe)
p i
teach
house owners hew to buy the right kinds of go ;o'd pant for their purpose
and how to get out of the paints they buy t•►Ye• good service of whic h
they ape Eagle,
the Need of Classification of Paint s
rs*ma ot
imam
ssful
tie
It maintenan
Sire
building and inferior paint as
hod s
*
and paints that have made the s.iombitolk4limill.401,110
and'
technical for craftsmen . and l _.
and mourn heat(nsul
ing plants are distinct improvements
but ,
u
appropriate prec 0hegs
MaWagiOlkiL
MaWagiO
4d parts
of the structure, they tend: to i
;which
e th4
.,
moisture leads to early paint fail.
and Ote r
eti*Ltmi way modern 'developments in p
giv
better pain
,'!
than OP
- ever had before but there illsig. . MIFO Ilo MOW'
of good pai
on ti is 1 and t
r a correc t
so mid&
and hous e
and
r Okii1r aid rther t.
ownex` S to hot know UPI*
the
4481EPOctly.
public good paints tMillillWidIgrMik-didifthg
unless w
gat.ak
make it possible for each good paint to be soa maintai
that it will give the good service of which i
pab , To a
maint
41*
:=Imt
atw.o
Wafts
iimnemot
ms's we t
em
' fed
:as. at It Ines
t
fication and gra&o .,
The work-lag ova:-
i1ble - i:n,s
21196
atri,oirs
of
®I
wt
a classification of
f or :arpplie
*mu+
t 15
roug
paints
# et'h ' with
den and maitntema nee is a i ,m-tly
-12-
technical problem that must be handled by paint technologists, that i s
to say by the paint manufacturers . Moreover it is a problem of the
industry as a whole through group action because there is obviousl y
little or nothing that an individual manufacturer can do about it b y
himself. Meantime those who deal in paint must continue to sell pain t
pretty much as they have been doing unless they can give the time an d
effort to closer technical study of the situation and individual con tact with their painter and owner customers to help them avoid th e
more serious mistakes about which there is now general agreement .
There is„ however, one suggestion that the writer would like to leav e
with paint dealers . That suggestion is to make a regular practice o f
keeping track of a fair sample of paint sales and observing the servic e
obtained by the customers over a period of years . In the smaller cities ,
at least, this should not be a very heavy burden and it has the highl y
important advantage of letting the dealer know what sort of servic e
his customers actually receive with the material he sells them . As
a rule, the dealer learns only about jobs that turn out badly and lea d
to complaints . No matter how good his paint there will be some complaints, the real causes of which could be determined to everyone' s
satisfaction much more successfully if the dealer could point specific ally to other houses painted perhaps from the same shipment of pain t
on which satisfactory service was being obtained . Such comparisons ,
if made conscientiously, will almost invariably show that the pain t
was capable of giving good service, but failed to do so for some on e
or more of the reasons discussed in this article . It rill also restor e
the dealer's confidence in the paint he is selling and make him les s
inclined to experiment with some new brand that offers no greate r
prospect of avoiding complaints and may even increase them by bringin g
about more heterogeneous combinations of different kinds of paint o n
the houses of his customers .
Paint capable of giving good service sometimes gives bad service in actual practice . Th e
house shown at the left was painted with a high-priced paint about one year before the photo graphs were taken . The bad cracking that developed has been observed on other houses o n
which this paint was applied over previous coats of paints of other types . The views at th e
right show the excellent service given by the brand of paint in question in an exposure test b y
the Forest Products Laboratory . The test panel consists of one board each of redwood, white 'ss +
■
pine, Douglas fir, and southern yellow pine, painted with three coats of the paint in question .
and exposed at 45° facing south (a very severe condition) for 2 3/4 years. The square showin g
fine checking of the paint is an area only 1 inch by 1 inch in actual size .
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