--MI NNI=}1m–
-Mar
in"
THE AIBRASIVE RESISTANCE Of WOOD
AS DETERMINED WITH THE U. S. NAVY
WEAR-TEST MACI-IINIE
1948
(No. P1132
UNITED STATESI-DEPARTMENT OF AGRICULTURE
— SOREST SERVICE
OREST
PRODUCTS LABORATORY
i_LJ
Madison 5, Wisconsin
In Cooperation with the University of VViosessia
THE ABRASIVE RESISTANCE OF WOOD AS DETERMINED WITH
TBE U. S. NAVY WEAR-TEST MACHINE
W. G. YOUNGZUIST, Engineer
and BERT P. MUNTHE, Engineer
BY
Forest Products Laboratory,1 Forest Service
U. S. Department of Agriculture
Summary
This report presents the results of an investigation at the U. S. Forest
Products Laboratory concerning the feasibility of using a newly designed
Navy wear-test machine for determining the abrasive resistance of wood.
Closely matched samples from 21 trees, representing 15 different species,
were tested. The data obtained are analyzed both with respect to the test-!
ing procedures used and as to the validity of the data obtained.
Comparative tests of closely matched specimens indicate that the method of
test used gives reproducible results. Further research on testing details
will be required before this method of test can be standardized.
The data obtained give results Which place the various species tested in
about the order to be expected from actual experience. The actual order of
species showing about the same amount of wear is probably not significant.
The much greater wear resistance of end-grain surfaces is clearly indicated
for all species tested. No clear, uniform relationship between wear
resistance and specific gravity was found.
The results obtained indicate that this wear-test machine should be a
valuable aid in making comparisons between new flooring materials and the
wood species commonly used for flooring.
Introduction
The U. S. Forest Products Laboratory has long been interested in the abrasion
resistance of wood as related to its use as a flooring material. The service
–Maintained at Madison, Wis., in cooperation with the University of
Wisconsin.
Rept. 81732
-1-
'4...,.;riculture,:.a6.. 3 on
behavior of the species of wood =commonly used for flooring can be predicted
with some accuracy; this is not trUe, h owever, for other species of wood and
various types of flooring Materials. Actual service-tests of flooring
materials are expensive, difficult to duplicate, and require long periods of
time for completion. Consequently,, a simple abrasion test that would indicate
the wear resistance of these materials would be of great value.
During the recent war, this Laboratory was called upon to assist the United
States Navy in the development of a satisfactory substitute for teak as ship
decking. As an aid in this work the Laboratory constructed a duplicate of the
wear-test machine designed and built by the Navy Materials Laboratory..? This
machine was used in an extensive investigation of the comparative wear
resistance of teak and a large number of modified wood materials. The Navy
wear machine was designed primarily for tests of ship walkway materials and
no claims are made as to its suitability for tests of other materials.
After completion of the modified wood study, the Laboratory decided to
investigate the possibility of using this wear-test machine as a wood-abrasion
tester. The results of this investigation are outlined in this report.
Description of Material
Tests were made on some of the species of wood commonly used for flooring,
together with other available species, included to provide a wide range in
specific gravity. The following tabulation gives both the species and the
number of trees represented.
Species
.(common
Species
botanical names) _ and botanical
..:
Hickory (Carya species) Maple, sugar (Acer saccharophorum) Ash, white (Fraxinus americana) Oak (Quercus species) Pine, southern yellow (Pinus sp.) .. Beech (Fagus grandifolii1-777 .... Douglas-fir (Pseudotsuga taxifolia) Birch, yellow (Betula lutea) Spruce, Sitka (Picea sitchensis) . Poplar, yellow TETT-Todendron tulipifera) .. Baldcypress (Taxodium distichum) Teak (Tectona grandis). thaya TREaTTsp.) . Pine,"Bastarn white (Pinus strobus).., Redwood (Sequoia sempervireT157---
NUMber,of trees
represented
L'
1
1
1
., ...
3
1
3
.;..o..Nowl". ..... a
. •
. 1
3
1
1
1
1
1
1
D,,,H,6 and Nestlen, H., A New Machine for Measuring
Wear Resistance of Walkway Materials, ASTM Bull. No. 132, Jan. 1945.
Rept, 817322
All of the specimens were obtained from air-seasoned or kiln-dried
Laboratory stock that was relatively free from knots, checks, cross grain,
or other growth characteristics that might influence direct comparisons
between tests. Except for the beech and teak, all material was in plank
form ranging in thickness from 3 to 4 inches with a minimum length of 5
feet: The beech was obtained from a board about 1 inch thick, while the
teak specimens were obtained from 6-inch square stock 12 inches long.
Specimens cut from the dry material were conditioned at 70° F, and 64 percent relative humidity until they reached approximately constant weight.
Marking and Matching
Figure 1 shows the cutting method used to obtain matched specimens from
2- by 2- by 56-inch bolts. Each bolt provided sufficient material for two
complete sets of specimens. Specimens of only the "A" series were used.
The teak specimens were matched in a similar manner insofar as the limited
amount of material would permit. The 1-inch thickness of the flat-aawn
beech board made it necessary to edge glue side-matched material in order
to obtain the required width for the radial and end-grain specimens.
As shown in figure 1, each specimen was marked with a code consisting of'
letters and numerals which identified it completely as to origin and intended
use.
Methods of Test
The Navy wear-test machine used is shown in figure 2. The abrasive wear
on the specimen is obtained by grinding against a revolving steel disk
covered with a loose abrasive. The disk upon which the abrasive is
distributed revolves clockwise at a uniform speed of approximately 23.5
revolutions per minute, while the specimen and specimen holder revolve
clockwise at a uniform speed of approximately 32.5 revolutions per minute.
The specimen is secured to the holder by means of two metal clamps. The
holder is designed with a universal coupling in order to maintain uniform
contact between the specimen surface and the revolving disk, Hardened
steel cams and cam followers lift the specimen a distance of 1/16 inch and
drop it back into contact with the abrading disk twice during each revolution
of the specimen. A dead weight of"10 pounds is mounted on the top of the
specimen holder.
The abrasive grit is distributed from the mechanically agitated hopper to the
abrading disk at the rate of-approximately 46 grams per minute. The grit used
throughout all tests was a No. 80 commercial aluminum oxide. New abrasive was
used for all tests.
A predetermining revolution counter automatically stopped the machine after
the desired number of abrading-disk revolutions had been reached.
Rept. 81732 - 3-
The amount of wear during a stated number of revolutions of the-.abrading-disk
was determined by measuring both the loss in thickness in inches and the
loss in weight in grams. The thickness was measured with a 0.001-inchdial
gage at the five points shown in figure 3.. The points of measurement were
accurately located on the wearing face of tie specimen by means of a template.
The loss of weight was determined by weighing the specimen at stated intervals
during the test. The lighter specimens were weighed to the nearest 0.001
gram while the heavier specimens and the specimens glued to metal plates were
weighed to the nearest 0.01 gram.
Specimens in which the wear was relatively rapid were tested for a total of
500 revolutions, wear being measured after every 100 revolutions. All other
specimens were tested for a total of 1,000 revolutions, with wear measured
after every 200 revolutions.
In order to minimize the effects of.changes in moisture content, all specimens
were conditioned and tested in a room maintained at a temperature of 75° F.
and a relative, humidity of 64 percent.
Test Results
Individual test results are given in table 1. Specimens tested to 500
revolutions only are indicated by footnote g . The wear data shown for
these specimens were obtained by'doubling the values obtained at 500
revolutions. The coefficient of variation in wear within each group of
four matched specimens is shown in column 6.
Table 2 shows the relative order of wear resistance and specific gravity
of all samples tested. , Test species are listed in the order of increasing
wear as determined from tests on the tangential (flat-grain) surface. The
respective order of wear on the radial (edge-grain) and end-grain surfaces
is indicated numerically in colymns 6 and 8. Column 10 shows the relative
numerical order of the specific gravities, with the highest specific gravity
having a- value .of 1.
Analysis of Results
Lacking comparative service test data with matched specimens, it was
p ecessary to analyze the results of the abrading tests on the basis of their
greement with the abrasive resistance of wood as determined by practical
experience. Wide acceptance of this method of determining the abrasion
resistance of wood will depend on the development of a standardized•eihod
of test and obviously on the validity of the data obtained. The abrasion
resistance data obtained were therefore analyzed with respect to both of
these considerations.
Root, 1117,2
Analysis of Test Methods
In order: todetermine the most satisfactory procedure, , the amount of wear
was, determined by measuring both the loss in thickness in inches andthe
loss of weight in grams. A study of the data in table 1 indicates that
.loss of weight alone is not a reliable criterion of the abrasive resistance
of wood.,.-Test species varied considerably in density, and as- a consequence
,equal weight losses do not necessarily represent equal losse6 of volume.
This is illustrated in the. following tabulation of data taken from table 1.
Loss of weight
after 1,000 revolutions of the
Species
abrading disk
Grams
Sitka spruce (sample 3) Hard maple... Yellow-poplar Sitka spruce (sample 1) Hickory Southern yellow pine (sample 3) Douglas-fir (sample 3) .
Douglas-fir (sample 1) .. White pine ....
.
Thickness loss after
1,000 revolutions
of the abrading
disk
Inch
0.27
0.0116
.30
.35
.35
.37
.50
.0066
.50
.52
1.56
.0144
.0143
.0386
.0142
.0167
.0056
.0088
These data indicate the necessity of considering the loss in weight in
conjunction with the density of the material being tested. In tests of
wood this is complicated by the fact that the average density of the test
specimen does not always represent the density of the abraded surface. This
is especially true of specimens abraded on the flat-grain surface, where the
wear can be entirely in the dense summerwood, in the less dense springwood,
or in any combination of the two. An attempt was made to correlate the loss
of weight in grams with the specific gravity of the material worn away. This
attempt was not successful, possibly due to the difficulty of measuring the
small quantities involved.
The close agreement in the results of separate tests of matched specimens
indicates that the results are rather closely reproducible whether loss of
weight or thickness as measured. Minor variations in thickness loss within
groups of matched specimens did not necessarily show similar variations in
weight loss.
The methods of test used in this study were, in general, closely patterned
after those developed by the designers of this testing machine, but others
were selected arbitrarily. Further studies will be required before this
abrasion test can be considered as a standardized test for wood.
Rept R1732
-5-
Some of the items which require further study are outlined below.
Effect of allowable variations in the commercial abrasive used.
Effect of moisture content and temperature on the abrasive
resistance of wood.
3. Effect of the rate of abrasive wear.
4 ."Effect of minor variations in the height through which the
specimen is dropped.
5. Effect of wear on the steel abrading disk.
6. Establishment of a standard method of reporting the test
results.
Analysis of Data
As previously mentioned, some specimens were only tested to 500 revolutions
of the abrading disk and results doubled for the 1,000 revolution index in
table 1. This method was used in view of the straight-line nature of Most
revolution -- wear-plot graphs. A few tests indicated that actual extra- •
polation of the data would change the tabulated data by only negligible
atounts.
The data in table 1 allow comparison between four closely matched end-grain,
tangential, or radial specimens. In all cases the end-grain specimens are
significantly more resistant to wear than the radial or tangential specimens.
Comparisons, between the average values obtained for the four radial and
tangential specimens of each species show that the radial wear is somewhat
greater in the majority of the cases, but the trend is not uniform or welldefined. The relationship of wear to specific gravity for those species
represented by samples from three different trees is also not consistent.
Growth characteristics or structure variation may possibly cause some of
these , inconsistencies.
The data presented in this study
statistical analysis, but in all
oak the coefficient of variation
specimens. This appears to be in
tangential surfaces.
are probably too limited to justify a
cases except those of hard maple and white
is greater for the tangential than the radial
keeping with the more variable nature of the
The summary of average data in table 2 showing the relative order of wear
resistance for all samples tested was included to facilitate wear-resistance
comparisons between species and between the various surfaces abraded. Me
data in columns 4, 6, and 8 indicate a closer agreement in the relative order
of wear resistance as determined by tests on the tangential and radial surfaces,
than as determined by end,-grain tests. The smaller numerical spread in the
end-grain values probably accounts for some of these discrepancies. The data
in column 10 indicate the general relationship between specific gravity and
wear.
The straight-line nature of the wear caused by a given number of revolutions
is shown for all species tested in figures 4, 5, and 6. Each point on these
charts represents the averages of four individual tests.
Rept. A1732
Pigure 7 shows the manner in which the abrasive wear in inches after 1,000
revolutions of the abrading disk varies with the specific gravity of the
specimen. In general, the species of high specific gravity have the greatest
wear resistance, while the specimens of low specific gravity have the least
wear resistance. The teak and Sitka spruce specimens are notable exceptions
to the general trend.
One possible use of a test of this kind would be as a flooring material
acceptance test. A specification admitting only material showing a wear
of less than 0.01 inch in 1,000 revolutions would thus admit end-grain
hickory, hard maple, beech, yellow birch, white ash, white oak, some southern
yellow pine, flat-grain hickory and maple, and also edge-grain hickory. A
specification calling for a flat- or edge-grain material with a limiting wear
factor of 0.02 inch would admit hickory, maple, ash, oak, beech, and possibly
some southern yellow pine. Increasing this wear factor to 0.03 inch would
also admit yellow birch, Douglas-fir, and possibly some Sitka spruce.
The data presented in figure 7 are shown in figure 8 in the form of a bar
chart in which the species tested are placed in the order of wear resistance.
The average specific gravity of each group of four specimens is shown directly
above. In general, the wear resistance of each specimen tested is in the
order that actual experience has shown to be proper. The chart again
illustrates the fact that specific gravity values alone are not reliable
criterions as to the abrasive resistance of wood.
Conclusions
The following conclusions are based on the results obtained in this
preliminary investigation of the abrasive resistance of wood as measured
by the Navy wear-test machine.
This method of test places the various species tested in about the order
to be expected from actual experience. The actual order of the species
showing about the same amount of wear is probably not significant.
Within each species tested it was found that the wear resistance of the
end-grain surfaces was significantly higher than that of either the radial
or tangential. Ii most instances the radial surfaces seem to be slightly
less wear resistant than the tangential surfaces, but the trend is not
well-defined.
The data show that, for most species tested, the results obtained from the
four closely matched specimens abraded on the tangential surfaces are more
variable than those from the specimens abraded on the radial faces.
No definite relationship was found to exist between wear resistance and
specific gravity within the species represented by samples from three
different trees.
Rep7t, R1732
-7-
The Navy wear-test,machine appears to provide a ready means of measuring
the comparative abrasion resistance of various species of woocL Further
research would be required in order to interpret these results in terms.
of the wear resistance of wood in actual service. This research should
also be directed towards the development of standard test procedures and
standard methods of reporting the test results. This machine should prove
udeful in making comparisons between the wear resistance of newly developed
flooring materials and that of the wood species commonly used for flooring.
Rept,. R1732
Table I.-Nav y-machine wear data for 15 species of wood, based on 1,000
revolutions of the abrading disk
:Specimen : Specific : Loss in : Average : Coefficient of
: variation (wear)
: gravityl : weight ; wear Surface
abraded
:
(1)
(2)
:
(3)
:
(4)
:
(5)
•
Inch :
Grams :
: Number :
:
:
Hard maple (Ater saccharophorum)
(Average moisture content 11.8 percent)
End grain...
Do.
Do.
Do.
Average...
Tangential.. :
Do.
:
Do.
:
:
Do.
Average...:
M-1
M-2
M-3
M-4
0.64
.63
.63
.63
.63
••
Percent
0.0074
.0060
.0062
.0066
.0066
:
:
•
:
9.38
.46
.48
.0096
.0088
.0086
.0088
.0090
:
:
:
:
:
14.92
.69
.69
.79
.64
.70
.0122
.0120
.0126
.0098
.0116
:
:
:
:
:
:
0.24
.28
.35
.31
.30
.52
.44
.48
.64
.64
.63
.62
.63
MT-1
MT-2
MT-3
MT-4
:
:
:
(6)
•
•
Radial......:
Do.
:
Do.
:
:
Do.
Average...:
.66
.64
.64
.64
.64
MR-1
MR-2
MR-3
MR-4
••
•
•
•
•
•
10,814
White oak (Quercus sp.)
(Average moisture content 11.9 p erce nt)
End grain...:
Do.
•
Do.
Do.
Average...:
0 -1
0-2
0-3
0-4
Tangential..:
Do.
•
Do.
•
Do.
Average...:
OT-1
OT-2
OT-3
OT-4
Radial :
Do.
:
Do.
:
Do.
Average...:
OR-1
OR-2
OR-3
OR-4
Rept, 1732
:
:
:
:
:
:
:
.64
:
.55 :
:
:
:
:
:
.62
.64
.65
.65
.64
.64
.64
,66
.67
.65
.65
.65
.68
.67
.66
.53
.0098
:
.54
:
.56
:
:
:
:
:
:
1.13
1.10
1.16
1.27
1.16
:
:
:
:
:
:
:
:
:
:
1.30
1.31
1.17
1.20
1.25
.0100
.0097
:
.0168
:
.0176
.0
0:
.0166
:
:
:
:
.0188
:
:
:
.0194
.0174
:
.0176
.0183
:
:
:
:
2.66
5.02
16.57
(Sheet 1 of 11 sheets)
Continued
Table 1.--Navy.rmachine wear data for 15 species of wood, based on 1,000
revolutions of the abrading disk (continued)
Surface :Specimen : Specific : Loss in ; Average abraded :
: gravity! : weight : wear (1)
:
(2)
:
(3)
:
(4)
Inch :
Grams
: Number, :
:
(5)
:
Coefficient of
: variation (wear)
(6)
Percent
Yellow birch (Betula lutea)
(Average moisture cdntent 12.2 percent)
0.47
: 0.0092 :
:46
.45
_.41
:
:
:.
.0098 :
.0080
6/45
:
.0088 :
1.36
1.46
1.47
;
;
.0260 :
.0266
End grain...: ' B-1
Do.
:
B-2
Do.
:
B-3
Do.
:
B-4
Average...:
:
:
:
:
:
0.56
.56
Tangential.',: BT-1
Do.
:: BT-2
Do.
;,- BT-3
Do.
. BT-4
Average..:
:
:
.61
.
:
:
.60
.60
.60
:
:
;
1.30
:
.60
;
1.40. :
Radial BR-1
Do.
: BR-2
Do.
: BR-3
: Br-4
Do.
Average...:
:
:
.59
;
.58
.59
:
:
1.53
1.52
1,50
:
:
:
.58
:
1,48
:
.0238
.0236
.0216
.0226
.58
:
1.50
:
.0229 :
:
:
:
:
:
:
End grain...:
Do.
.
Do.
Do.
verage...:
A
A-4
:
:
:
9.65
:
.0
(0)25
14 :
13.83
:
:
:
:
:
.66
3
.39
:
.0086
:
.63
f
.50
:
.0085 :
:
.64
.65
.62
:
.83
:
.74
:
:
.78
:
.0128 I
.0114 .
: glIgt :
.66
.64
:
.78
:
.
,78
:
.0127 :
.65
.65
.65
:
:
:
1,10
.64
.65
:
:
:
1,10
1.11
:
:
•.
•.
.0180
.0173
.0178
.0200
1,09
:
.0183 :
:
1
:
:
:
Radial • AR-1
:
:
::
AR-2
Do.
Do.
: AR-3, :
Do.
: AR-4, :
Average...:
:
Zejt. 81732
•
.0082 ..:
4.42
Nhite ash (Fraxinus americana)
(Average moisture content 9.5:pooeloro70c4ent)
;
:
..60
;
:
:
160
A-1
.0080
:
.65 :
A-2
.60
:
:
:
.38
;
A-3
.66
:
Tangential.: AT-1
Do.
. AT-2
Do.
: AT-3
: AT-4
Do.
Average...:
:
.58
..58
.57
13.11
9.13
.
6.49
(Sheet 2 of 11 sheets)
Continued
'
Table 1.---Navy-machine wear data for 15 species of wood based on 1,0.00
abrading disk (continued)
revolutionsofd
Surface
abraded
(1)
:Specimen : Specific : Loss in : Average : Coelficient of
: variation (wear)
: gravityl : weight : wear
:
(2)
:
(3)
:
•
:
(4)
:'Number :
:
:
(6)
(5)
Grams :
:
-
:
:
:
:
Inch
Percent
Hickory (Carya sp.)
(Average moisture content 12.2 percent)
End grain...:
Do.
:
Do.
:
Do.
Average.:
:
:
:
:
:
:
0.36
.39
.32
.40
.37
:
:
:
:
:
.70
.75
.73
.70
.72
:
:
:
:
;
.51
:
.48
.51
.62
:
..
:
.53
:
.0079 :
.
:
.
.0090 ..
.0072 :
.0110
:
:
H-3
H-4
:
:
Tangential..: HT-1
Do.
: HT-2
: ET-3
Do.
Do.
: ET-4
Average....
Radial HR-1
Do.
: FR-2
Do.
: HR-3
Do.
: HR-4
Average...:
: 0 : 0046: :
.0058
:
:
.0064
:
.0056 1
:
0.72
.72
.68
.68
.70
H-1
H-2
:
:
.72
.78
:
:
.56
.54
:
:
:
:
.66
:
.
.71
.75
.58
:
:
.74
:
.58
:
16.84
.
0088
.
0064
.
0066
.0098
21.13
.
0078
.0088 :
19.05
Beech (Fagus grandifolia)
(Average moisture content 9.8 percent)
•
:
:
End grain...: Be-1
.59
:
:
Do.
: Be-2
.59
.60
•.
Do.
:
: Be-33
.60
•.
:
Do.
: Be-4
:
Average...:
.59
:
:
.0081 :
.0085
.43
.45
:
:
..0076
.43
1.08
:
,.:
:
.95
:
:
.
Tangential..: BeT-1
: BeT-2
Do.
Do.
: BeT-3
Do.
: BeT-4
Average...:
.40
.43
.62
.61
..63
:
.0078 :
.0080 :
•
.0178 :
.0153 :
1 040
:
.0201
.66
1.97
:
.63
1.35
:
.0265 :
.0199 :
•
.
:
:
:
.0272
.0271
.0249 :
.0281 :
:
.0268 :
:
:
1.72
•.
:
• BeR-1
.61
Radial 1.76
:
.62
:
: BeR-2
.
Do.
•.
1
.65
.63
:
Do.
: BeR-3 :
:
1.75
.61
Do.
: BeR-4
1.72
.62
:
Average...:
:
Rept. R1732
:
•
4.90
24.13
5.07
:
(Sheet 3 of 11 sheets)
Continued
Table 1.--Navy-machine wear data for 15 species of wood based on 1,000
revolutions of the abrading disk (continued)
Surface :Specimen : Specific, : Loss in : Average : Coefficient of
: variation (wear)
abraded :
: gravity± : weight : wear
(1)
:
(2)
:
----------- : :
: Number :
..
:
(3)
•
:
(4)
:
:
Grams :
Khaya (Khaya sp.)
(Average moisture content
End grain...: AM-1
Do.
: AM-2
Do.
: AM-3
: AM-4
Do.
Average.:
:
0.42
.42
:
,41
.41
.42
Tangential? : AMT-1 :
: AMT-2
Do.
Do.
: AMT-3
Do.
:AMT-4
Average...:
. 2
Radial-
• AMR-1
Do.
: AMR-2
Do.
: AMR-3
Do.
::AMR-4
Average...:
•.
:
:
:
:
:
:
.40
.41
.
:
:
.40
.42
.41
.42
.41
.42
.41
.42
11.2
(5)
(6)
:
Percent
Inch :
:
percent)
: 0.0202 :
0.78
:Cg
.80 :
..72
•.
.0226 :
•:
.71
.0212 :
:
.
.75
:
3.50
:
3.50
3.1
3,06
:
..
..
:
:
3.26
3.36
3.14
:
:
3.28
:
:
:
5.2 8
..F771
.
.
11.53
..0716 :
.0746 :
.0700 :
.0716 :
.0720 :
3.26
2.
67
Teak (Tectona grandis)
(Average moisture content 9.0 percent)
•
•
•
•
:
.56
.56
.57
.57
.56
••
:
••
:
:
1.15
1.15
1.15
1.15
1.15
:
:
:
:
.0251 •
.0241
1
...0!5
Tangential-.: TT-1
Do.
: TT-2
Do.
: TT-3
Do.
: TT-4
Average...:
•
.58
:
4.10
:
.57
::
•57
:
.0694 .0672 :
.0632
.0668
.0666 :
Radial- :
End grain... :T-1
Do.
:
T-2
Do. =
:
T-3
Do.
:
T-4
Average...:
2
TR-1
Do.
; TR-2
Do.
: TR-3
Do.
: TR-4
Average...:
:
:
:
.55
13,
.
:
:
:
.57
:
134.94
.58
.56
.56
:
;
:
1- .0/84
:
5.10
:
.0782
.0842 :
:
.56
.56
:
;
:
:
..0830
.0828 :
:
55.0) (0)
•
Sept. 81732
•
(Sheet
1.86
-
3.86
3.81
of 11 sheets)
Continued
4
Table 1.--Navy-machine wear data for 15spect.esof1121:2LPtlEd2nlL222
:ve-.7olutions of the abrading disk continued
Surfaee :Specimen : Specific : Loss in : Average : Coefficient of
abraded :
: gravityl : weight : wear : variation (wear)
(1)
(6)
: (2)
:
(4)
(3)
(5)
Number :
Inch :
Grams
Percent
Yellow poplar :(to'i•iedendron'taliPifer4)
(Average moisture content 9.9 percent)
End grain...:
Do.
Do.
:
Do.
:
Average...;
P-1
P-2
P-3
P-4
•.
0.46
.46
.47
.47
.46
0.33
.37
.36
.34
.35
:
:
:
:
:
.45
.42
.45
.42
.44
2.34
3.42
2.34
2.40
2.62
:
.45
.46
.44
.44
.45
.•
:
:
:
:
Tangential? :
Do.
Do.
Do.
Average...:
PT-1
PT-2
PT-3 PT-4
Radial? •
Do.
Do.
:
Do.
:
Average .. .:
.
PR-1
PR-2
PR-3
PR-4
:
End grain...: DFL-1
Do.
: DFL-2
Do.
: DFL-3
Do.
: DFL-4
Average...:
0.0137
.0136
.0148
.0146
.0142
:
:
:
:
432
.
•.
•.
•.
..
•.
2.96
3.02
3.06
3.08
3.02
.0456
.0778
.0440
.0456
.0532
:
:
:
:
:
•.
30.80:-
.0592
.0580
.0612
.0610
.0598
:
:
:
:
.
:
DOUglaa7. tir'4 .(PSeudOtsuga taxifolla)
“Verage moisture content-11.9 percent)
:
.
.0116
.43
•.
.40
.0154 :
.45
.47
.0158
.44
:
.62
.0143 :
.44
:
.57
.44
-.
.52
:
.0143
,
•
•.
•.
Tangential? :141A,T-1
Do.
:DFLT-2
Do.
:DFLT-5
Do.
:DFLT-4
Average...:
:
:
Radial?
•DFLR-1
Do.
:DFLR-2
Do.
:DFLR-3
Do.:DFLR-4
.
Average...:
:
:
Rept. -R1732
:
:
:
:
:
;
:
:
.46
.39
.46
.41
.43
.42
.42
.43
.42
.42
•.
2.14
:
1.92
-.
1.42
1.64
1.78
:
1.60
1.68
1.60
1.86
1.68
:
:
:
:
:
.0636
.0448
. .0440
.0420
.0486
.0332
.0396
.0408
.0456
.0398
1344
:
:
20.72
:
:
:
;
•
12.83
(Sheet 5 of 11 sheets)
Continued
Table 1.--Navy machine wear data for 15 species of wood, based on 1,000
revolutions of the abrading disk (continued)
Surface :Specimen : Specific : Loss in : Aver4gT ; Ccefftcient`cf
: gravityl : weight : wear" :variation (wear)
abraded :
--.----(3)
(2)
:
(1)
:
- - ... .- ....., - !...- . , .
•
Number:
(4)
:
:
:
:
Grans :
.
(6)
(5)
:
:
Inch
.
.
Percent
Dcug1as-fir-2( Pseudops uga taxifolia)
(Average moisture content 11.8 percent)
•
En 4 grain...:
DFMr1
:
DFM-2 :
Do. •
DFM-3 :
Do.
Do.
DFM-4 :
•
Average...:
0.48
.48
.5o
.5o
.49
•.
•
rFmR-3. :
DFMR-2 :
rFmR -3 ':_
DFMR-4 :
:
End grain...:
Do.
Do.
•
•
Do.
Average,..:
0.62 ; 0.0128
.0144
.64. :
.0118
.52 :
.0138
.48 :
.0132 :
.56 :
.50
.49
.49
.49
.49
.48
.49
.48
.49
..48
.94
1.64
.85
1.37
1.20
:
:
:
:
:
:
•.
:
:
:
:
:
:
1.56
1.57 :
1.52 :
1.55 :
1.55 1
:
.0180
.0350
.0152
.0254
.0234 :
.
.0308
.0300 .
.0302
.0294
.0301
.
: .
.•
Douglas-fir-3 (Pseudotsuga.taxifolia)
(Average moisture content 11.4 percent)
DFH-1 :
DFH-2
DFH-3
DFH-4
8.66
.
:
Tangential :
DFMT-1
:
Do.
DFMr-2 :
Do.
rEmT-3 :
DM-4 :
Do.
Average :
Radial Do.
Do.
Do.
Avera&e, :
:
:
•:
•.
.52
.52
.47
.50 :
.50
51
.51
.50
.50
.50
37.82
1.92
.0160
.0124
.0150
.0140
.0144
10.66
.0184
.0304
.0412
.0232
.0284
34.91
7
•
Tangential? :
Do.
•
Do.
•
Do.
•
Average...:
DFHT-1
DFIfr-2 ;
DFHT-3
DFHT-4
2
RadialDo.
•
Do.
Do.
Average •
DFFIR-1
DFBR-2 4
DFER,3
EFER-4
2ept. R1732
52
.49
.51
.50
.50
:
.
•.
,49
.49
.48
,50
,49
.
•. .
•
•
•
2
.
1.18
1.46
2.14
1.14
1.48
2.20
2.04
2.16
2.16
2,14
:.
•.
•.
•.
:.
0452
0436
.0440
.0416
,0436
:
:
:
;
:
3.43
(Sheet 6 of 11 sheets)
Continued
Table 1.--Navy machine . wear data for 15 species of wood, based on 1,000
revolutions of the abrading disk (continued)
Surface
abraded
(1)
:Specimen : Specific : Loss in
1
gravity- : weight
(4)
(2)
:
(3)
: Average
•
:
:
Grams
Inch
: Number
wear
(5)
Coefficient of
variation (wear)
(6)
Percent
:
•
Southern yellow pine-1 (Pinus sp.)
(Average moisture content 12.4 percent)
End grain e
Do.
Do.
Do.
Average :
Tangential
Do.
Do.
Do.
:
Average :
SPL -1
SPL-2
SPL -3
SPL-4
:
SPLT-1
SPLT-2
SPLT-3
SPLT-4
o.66
.66
.6o
.6o
.63
0.76
0.0132
.76
.73
.59
.71
.0146
.0122
.0124
.64
.62
.63
.63
.63
2.31
2,06
2.20
2.09
2.16
.0300
,o365
.0270
.0315
.0312
.62
.68
2.18
2.16
2,25
2.09
2.17
•
•
8 .31
.0131
•
12.72
:
•
Radial Do.
Do.
Do.
Average SPLR-1
SPLR -2
SPLR-3
SPLR-4
:
.62
.68
.65
:
.0331
.0285
.0334
.0293
.0311
8.15
Southern yellow pine-2 (Pinus en.)
(Average moisture content 12.7 percent)
End grain Do.
Do.
Do.
Average :
Tangential Do.
Do.
Do.
:
Average SPM-1 :
SPM-2 :
SPM-3 :
SPM-4 :
:
SPMr-1 :
SP112-2 :
sPr1-3 :
SPNE-4 :
:
:
.0126
.0140
.0126
.0121
.0128
.58
.58
.59
.59
.58
.72
.75
.75
.63
.71
.59
.63
.58
.0241
.0158
.0224
.0197
.60
1.64
1.33
1.55
1.17
1.42
.6o
.59
.62
.58
.6o
1.88
1.80
1.91
1.96
1.89
.0298
.0282
.0294
:
:
.0340
.0304
:
:
.62
6.39
17.65
.0205
•
Radial Do.
Do.
Do.
Average...:
Rept. R1732
SPMR-1 SPMR-2 :
SP111-3 :
SPMR-4 :
8.31
(Sheet 7 of 11 sheets)
Continued
Table 1.--Navy-machine wear data for 15 species of Wood, based on 1,000
revolutions of the abrading disk (continued)
Surface
abraded
:Specimen : Specific, : Loss in : Average : Coefficient of
•
: gravity : weight : wear : variation (wear)
(1)
(2)
:
(4)
(3)
:
(5)
:
: Number :
:
:
End grain...:
Do.
Do.
Do.
Average...:
:
Grams :
Inch :
.
•.
.
.
sp.)
Southern yellow pine-3 (Pinus
(Average moisture content 12.5 percent)
.
.
.
SPH-1 •.
0.62
0.56 : o.0088 :
SPH2
.50
.62
.0072
•.
sPH-3
sPH-4
•.
.62
•.
.62
.44
.48
•.
•
.
.0102
.62
.50
:
.0088
•
•
.0223
:
•.
.0092
•
Tangential..:
Do.
Do.
Do.
Average...:
1.81
1.58
1.66
•.
.0178
:
.62
.62
1.54
•
.
1.65
•.
.0200
.0172
.0193
•
.61
•
.0209
•
.61
.61
1.32
1.21
SPHT-1
SPHT-2
SPHT-3
SPHT-4
.62
.63
.63
•
•
Radial Do.
Do.
Do.
Average
••• SPER-1
SPHR-2
SEER-3
: SPHR-4
:
(6)
Percent
.•
•
:
•
•
14.18
.•
•
•.
12.02
•
.61
.61
.0186
1.35
1.35
••
••
1.31
•
.0200
.0194
.0197
•
.•
•
.
•
••
4.93
•
Sitka spruce-1 (Picea aitchensis)
(Average moisture content 1.1765Wjent)
End grain.:
Do.
•
Do.
•
Do.
•
Average...:
SL-1
SL-2
Tangential2 :
Do.
Do.
Do.
Average...:
ELT-1
SLT-2
SLT-3
SLT-4
Radial-2
Do.
Do.
Do.
Average,..:
SLR-1
SLR-2
SLR- 3
SLR-4
Rapt'. n1732
SL - 4
:
.33
:
.33
.32
.32
.32
:
.35
:
.96
7?
1,06
.96
.92
.32
.36
.33
.36
.34
.32
.38
.33
.36
.35
.38
.38
.34
.31
•
1.44
1.26
1.36
1.28
1.34
•
•
.0174
.0167
.0163
.0164
.0167
:
.0318
,020'8
.0358
:
.0318
:
.0300
:
.0384
.0304
.0378
;
.0320
:
:
.0346
2.98
21.50
11.69
(Sheet 8 of 11 sheets)
Continued
Table 1.--Navy-machine wear data for 15 species of wood based on 1,000
revolutions of the abrading disk (continued)
Surface
abraded
:Specimen : Specific : Loss in : Average : Coefficient of
1
gravity- : weight : wear : variation (wear)
(2)
(1)
:
(3)
•
: Number
•.
(4)
(6)
(5)
Grams : Inch
Percent
•
Sitka spruce-2 (Picea sitchensis)
(Average moisture content 11.5 percent)
End grain...:
Do. •
Do.
Do.
Average...:
SM-1
SM-2
0.41
sm-3
.39
.39
Tangential-2 :
Do.
Do.
Do.
Average
SMT-1
SMT-2
Radial-
Do.
Do.
Do.
Average
SMR-1
SMR-2
.41
SM-4
.4o
.42
.38
SMT -3.42
SMT-4
.37
.40
0.0106
.0123
.0129
.0120
8. 12
1.70
1.34
1.24
.0424
0336
027o
.0352
.0346
18.27
1.62 0378
.0386
1.68
1.70 0414
.0380 1.64
.0390
1.66
4.28
.0120
1.36
1.40
.39
.39
.38
SMR -3
srm-4
0.28
.30
28
27
.28
.4o
.39
Sitka spruce-3 (Picea sitchensis)
(Average moisture content 11.6-percent)
End grain...:
Do.
•
•
Do.
Do.
•
Average...:
SH-1
SH-2
SH- 3
SH-4
Tangential-2 :
Do.
Do.
Do.
Average..
SHT-1
SHT-2
SHT-3
SHT-4
40
.40
.4o
4o
.40
.28
.27
.26
.27
.27
.40
.39
.40 .39
.40
•
1.68
1.82
1.78
1.56
1.70
.0112
.0111
.0124
.0115 .0116
54 10
.0376
0462
0346
036o .0386
13.51
•
Radial
Do.
Do.
Do.
Average...:
SER-1 :
SHR-2 :
SHR-3
SHR-4 :
41
40
1.98
2.04
40
1.94
.40
40
2.00
:
1.98
.0450
.0478
.0438
.0456
.0456
:
:
:
:
3.68
:
Rept. 81732
(Sheet 9 of 11 sheets)
Continued
Table .--Navy-machine wear data for 15 s ecies of wood, based on 1,000
revolutions of the abrading
(continued)
Surface :Specimen : Specific : Loss in
abraded :
: gravity_ : weight
(1)
:
n ••n
(2)
:
.....
Number :
:
••
End grain,..:
Do.
Do.
Do.
•
:
Do.
Do.
Do.
Average...:
End grain...:
Do.
Do.
Do.
Average...:
•
•
R-1
R72
R-3
R-4
RT-1
RT-2
RT-3
RT-4
RR-1
RR-2
RR-3
RE-4
Inch :
0.75
.76
.86
0.33
.33
.31
.31
.83
.80
3.94
3.86
4.12
4.46
4.10
.31
.33
.3o
•
.32
.32
.31
.31
:
5.14
5.22
5.34
5.52
.32
:
5.30
.32
•
.
;
Percent
0,0238
:0265
.029
.0293
6
.0273
9.96
•
.1142
,11o4
.1296
.1292
.1208
8.27
•.
•
.
•
.
.1446
.1512
.1588
•
•
•.
•.
.1630
.1544
5.28
White pine (Pinus strobus)
(Average moisture content (9.3 percent)
:
.
WP-1 •
.38
.0372
1.52
WP-2
.38
.0388 :
1.53
WP-3
.38
1.57
.0392
WP-4
.38
1.61
.0394
1.56
.0386
.38
WPT.,1
WPT-2
WPT-3
WPT-4
Radial-2
Do.
Do.
Do.
Average
WPR-1
WPR-!2
WPR-3
WPR-4
Gram :
,•
.3.2
Tangential?
Do.
Do.
Do.
Average
1732
.
,32
Radial?
(6)
Redwood (Seq
uoia sempervirens)
(Average moisture content 11. percent)
Average...:
Tangential
Do.
Do.
Do.
Average
: Coefficient of
:variation (wear)
Average
wear,
(4).
(3)
:. n •n•
:
.39
.40
.38
4.48
4.28
5.00
5.42
.38
•39
.39
.38
.38
.38
!
4.79
.1088
.0996
.1240
.1352
.1168
5.50
5.52
6.76
6.38
6.04
.1336
:
0.340
.1660
.1572
.1476
:
:
:
2.59
13.54
11.14
(Sheet 10 of 11 sheets)
Continued
Table I.-Navy-machine w5ar date for 15 species of wood, based on 1,000
revolutions of the abrading disk -ontinued)
Surface
abraded
(1)
Average
weer
:Specimeu : Specific : Loss in
giavityl : Weight
(3)
(2)
Number :
:
(4)
:
Gram
: Coefficient of
:variation (wear)
(6)
(5)
Percent
Inch
Baldcypress (Taxodium distichum)
(Average moisture content 11.5 percent)
•
End grain...:
•
Do.
•
Do.
Do.
Average...:
C-1
C-2
2
Tangential- :
Do.
Do.
Do.
Average
CT-1
CT-2
CT-3
CT-4
Radial2
Do.
Do.
Do.
Average...:
CR-1
CR-2
CR-3
CR-4
C-3
c-4
•
•
1 .3 3
0.41
.41
•
•
1.32
1.24
1.25
1.28
.4o
.4o
.4o
.42
:
:
:
:
:
:
:
.39
.42
.39
.4o
.41
.4o
.41
.4o
.4o
0.0308
.0322
.0311
.0297
.0310
•
3.32
.o548
.0626
.0518
2.34
2.60
2.26
2.42
2.40
.0602
.0574
8.59
.0598
2.66
2.36
2.38
2.52
2.48
.0540
.0548
.0564
.0562
4.57
•
Biased on weight when oven-dry and volume when tested. Oven-dry weights
were computed from weights when tested and from a moisture determination of specimens G1 and G2 (fig. 1).
These specimens were not abraded behond 500 revolutions. Actual test
values were doubled to provide the comparative values listed at
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(Sheet 11 of 11)
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specification.
z m 78949 F