Chapter XIV: Appendix: III

USEFUL TABLES

FRACTIONAL EQUIVALENTS FOR DECIMAL VALUES

================================================================
.0156 | 1/64 || .2656 | 17/64 || .5156 | 33/64 || .7656 | 49/64
.0312 | 1/32 || .5312 | 9/32 || .2812 | 17/32 || .7812 | 25/32
.0468 | 3/64 || .2968 | 19/64 || .5468 | 35/64 || .7968 | 51/64
.0625 | 1/64 || .3125 | 5/16 || .5625 | 9/16 || .8125 | 13/16
.0781 | 5/64 || .3281 | 21/64 || .5781 | 37/64 || .8281 | 53/64
.0937 | 3/32 || .3437 | 11/32 || .5937 | 19/32 || .8437 | 27/32
.1093 | 7/64 || .3593 | 23/64 || .6093 | 39/64 || .8593 | 55/64
.125 | 1/8 || .375 | 3/8 || .625 | 5/8 || .875 | 7/8
.1406 | 9/64 || .3906 | 25/64 || .6406 | 41/64 || .8906 | 57/64
.1562 | 5/32 || .4062 | 13/32 || .6562 | 21/32 || .9062 | 29/32
.1718 | 11/64 || .4218 | 27/64 || .6718 | 43/64 || .9218 | 59/64
.1875 | 3/16 || .4375 | 7/16 || .6875 | 11/16 || .9375 | 15/16
.2031 | 13/64 || .4531 | 29/64 || .7031 | 45/64 || .9531 | 61/64
.2187 | 7/32 || .4687 | 15/32 || .7187 | 23/32 || .9687 | 31/32
.2343 | 15/64 || .4843 | 31/64 || .7343 | 47/64 || .9843 | 63/64
.250 | 1/4 || .500 | 1/2 || .750 | 3/4 || 1.000 | 1
================================================================

Where rafter lengths are determined by multiplying unit lengths by the run, the answer will almost invariably result in a decimal. Such decimal values may be readily translated into fractional forms by means of the accompanying table.

Example: A roof of ⅓ pitch has a common rafter run of 14';
find the length of common rafter.

Answer: 14 × 14.42" = 201.88" or 16.82'. By the table, .82 = 53/64.
A carpenter, however, would not care for such accuracy; the
nearest 1/16" or even ⅛" would be sufficient.

WOOD AND MACHINE SCREW SIZES

The difference between consecutive sizes is .01316".

===================================================================
No. of | Size of || No. of | Size of || No. of | Size of
Screw | Number in || Screw | Number in || Screw | Number in
Gage | Decimals || Gage | Decimals || Gage | Decimals
--------+------------++--------+------------++--------+------------
000 | .03152 || 16 | .26840 || 34 | .50528
00 | .04486 || 17 | .28156 || 35 | .51844
0 | .05784 || 18 | .29472 || 36 | .53160
1 | .07100 || 19 | .30788 || 37 | .54476
2 | .08416 || 20 | .32104 || 38 | .55792
3 | .09732 || 21 | .33420 || 39 | .57108
4 | .11048 || 22 | .34736 || 40 | .58424
5 | .12364 || 23 | .36052 || 41 | .59740
6 | .13680 || 24 | .37368 || 42 | .61056
7 | .14996 || 25 | .38864 || 43 | .62372
8 | .16312 || 26 | .40000 || 44 | .63688
9 | .17628 || 27 | .41316 || 45 | .65004
10 | .18944 || 28 | .42632 || 46 | .66320
11 | .20260 || 29 | .43948 || 47 | .67636
12 | .21576 || 30 | .45264 || 48 | .68952
13 | .22892 || 31 | .46580 || 49 | .70268
14 | .24208 || 32 | .47896 || 50 | .71584
15 | .25524 || 33 | .49212 || |
--------+------------++--------+------------++--------+------------

Frequently the carpenter wishes to know the diameter of hole necessary to receive the shank of a screw of a certain gage. Should a screw gage be accessible, he may readily determine this. Should no gage be at hand, he may determine the size of hole by consulting the accompanying table of Wood and Machine Screw Sizes.

Example: What size bit must be selected to bore a hole for a
No. 10 screw. By the table, a No. 10 screw is .18944" in diameter.
By the table of Fractional Equivalents for Decimal Values it will
be seen that a 3/16" bit must be used. The test for gage of screw is
always made over the shank just below the head.

LENGTH AND NUMBER OF WIRE NAILS TO THE POUND

================================================================
Size |LENGTH|COMMON|CASING|FINISH|CLINCH|FENCE | FINE | GAL.
| INS. | | | | | | | SHINGLE
-----+------+------+------+------+------+------+------+---------
¾ | ¾ | | | | | | |
⅞ | ⅞ | | | | | | |
2d | 1 | 900 | | | | | 1440 |
3d | 1¼ | 615 | | | | | 810 | 568
4d | 1½ | 322 | 473 | 584 | | | 250 |
5d | 1¾ | 254 | | | | | |
6d | 2 | 200 | 180 | 300 | 157 | 114 | |
7d | 2¼ | 154 | | | | | |
8d | 2½ | 106 | 112 | 190 | 99 | 74 | |
9d | 2¾ | 85 | | | | | |
10d | 3 | 74 | 90 | 134 | 69 | 42 | |
12d | 3¼ | 57 | | | | | |
16d | 3½ | 46 | .| | | | |
20d | 4 | 29 | | | | | |
30d | 4½ | 23 | | | | | |
40d | 5 | 17 | | | | | |
50d | 5½ | 14 | | | | | |
60d | 6 | 11 | | | | | |
-----+------+------+------+------+------+------+------+------

Nails are sold in quantity by the keg, 100 lbs. of nails, exclusive of the keg. Twenty, 30, 40, 50 and 60d are "base." Other sizes have certain fixed additions per keg to this base price. For example, the price list adopted by manufacturers in 1896 allows an addition per keg of $.70 for 2d common, $.45 for 3d common, etc.

Wire nails are also bought and sold by weight, the size of wire according to the standard wire gage and the length in inches being taken into consideration in specifying the size and in fixing the price per pound.

Common wire nails are thick and have large flat heads. They are used in rough work where strength is desired. Finishing nails are used for fine work such as inside woodwork and cabinet work. Casing nails are somewhat thicker and stronger than finishing nails; they have smaller heads.

WIRE BRADS

====================================================================
Size, inches | ½ | ½ | ⅝ | ¾ | ¾ | ¾ | ⅞ | ⅞ | 1
Wire Gage, nos | 20 | 18 | 19 | 19 | 18 | 16 | 18 | 17 | 18
Approx no brads to lb. |7500|7200|4267|3556|2758|2600|2364|1781|2069
-----------------------+----+----+----+----+----+----+----+----+----
Size, inches | 1 | 1 | 1¼ | 1¼ | 1½ | 1½ | 1½ | 1¾ | 1¾
Wire Gage, nos | 17 | 16 | 17 | 16 | 16 | 15 | 14 | 15 | 14
Approx no brads to lb. |1558|1143|1246| 913| 761| 584| 500| 500| 406
-----------------------+----+----+----+----+----+----+----+----+----
Size, inches | 2 | 2 | 2½ | 2½ | 3 | 3 | 3 | |
Wire Gage, nos | 14 | 13 | 13 | 12 | 14 | 12 | 11 | |
Approx no brads to lb. | 350| 268| 214| 164| 150| 137| 105| |
-----------------------+----+----+----+----+----+----+----+----+----

BOARD MEASURE TABLE

==================================================================================
|
Size | Length, in Feet, of Joist, Scantling and Timber
in +----+----+----+----+----+----+----+----+----+----+----+----+----+----+-----
Inches| 12 | 14 | 16 | 18 | 20 | 22 | 24 | 26 | 28 | 30 | 32 | 34 | 36 | 38 | 40
-------+----+----+----+----+----+----+----+----+----+----+----+----+----+----+-----
2 × 4| 8| 9| 11| 12| 13| 15| 16| 17| 19| 20| 21| 23| 24| 25| 27
2 × 6| 12| 14| 16| 18| 20| 22| 24| 26| 28| 30| 32| 34| 36| 38| 40
2 × 8| 16| 19| 21| 24| 27| 29| 32| 35| 37| 40| 43| 45| 48| 51| 53
2 × 10| 20| 23| 27| 30| 33| 37| 40| 43| 47| 50| 53| 57| 60| 63| 67
2 × 12| 24| 28| 32| 36| 40| 44| 48| 52| 56| 60| 64| 68| 72| 76| 80
2 × 14| 28| 33| 37| 42| 47| 51| 56| 61| 65| 70| 75| 79| 84| 89| 93
3 × 6| 18| 21| 24| 27| 30| 33| 36| 39| 42| 45| 48| 51| 54| 57| 60
3 × 8| 24| 28| 32| 36| 40| 44| 48| 52| 56| 60| 64| 68| 72| 76| 80
3 × 10| 30| 35| 40| 45| 50| 55| 60| 65| 70| 75| 80| 85| 90| 95| 100
3 × 12| 36| 42| 48| 54| 60| 66| 72| 78| 84| 90| 96| 102| 108| 114| 120
3 × 14| 42| 49| 56| 63| 70| 77| 84| 91| 98| 105| 112| 119| 126| 133| 140
4 × 4| 16| 19| 21| 24| 27| 29| 32| 35| 37| 40| 43| 45| 48| 51| 53
4 × 6| 24| 28| 32| 36| 40| 44| 48| 52| 56| 60| 64| 68| 72| 76| 80
6 × 6| 36| 42| 48| 54| 60| 66| 72| 78| 84| 90| 96| 102| 108| 114| 120
6 × 8| 48| 56| 64| 72| 80| 88| 96| 104| 112| 120| 128| 136| 144| 152| 160
8 × 8| 64| 75| 85| 96| 107| 117| 128| 139| 149| 160| 171| 181| 192| 203| 213
8 × 10| 80| 93| 107| 120| 133| 147| 160| 173| 187| 200| 213| 227| 240| 253| 267
10 × 10| 100| 117| 133| 150| 167| 183| 200| 217| 233| 250| 267| 283| 300| 317| 333
10 × 12| 120| 140| 160| 180| 200| 220| 240| 260| 280| 300| 320| 340| 360| 380| 400
12 × 12| 144| 168| 192| 216| 240| 264| 288| 312| 336| 360| 384| 408| 432| 456| 480
12 × 14| 163| 196| 224| 252| 280| 308| 336| 364| 392| 420| 448| 476| 504| 532| 560
14 × 14| 196| 229| 261| 294| 327| 359| 392| 425| 457| 490| 523| 555| 588| 621| 653
-------+----+----+----+----+----+----+----+----+----+----+----+----+----+----+-----

STRENGTH OF MATERIALS

YELLOW PINE POSTS

Load in Tons

Length
in ft. Size in inches
4 × 4 5 × 5 6 × 6 7 × 7 8 × 8 9 × 9
8 4 5 6 7 8 9
10 3 4 5 6 7 8
12 2 3 4 5 6 7
14 1 2 3 4 5 6
16 1 2 3 4 5
18 1 2 3 4

HARD PINE BEAMS AND GIRDERS

Load in Tons

Length
in ft. Size in inches
2 × 6 3 × 6 4 × 6 6 × 6 8 × 8
6 1 1½ 2 3 5½
8 ¾ 1 1½ 2½ 5
10 ¾ 1¼ 2 4½
12 ½ 1 1½ 3
14 ½ 1 2½
16 ½ 2
18 1

STEEL I BEAMS

Load in Tons

Length Size in inches
in ft.
6 8 12
10 7 14 18
12 6 12 16
14 5 10 14
16 4 8 12
18 2 6 10
20 4 8
22 2 6
24 4

BRICK PIERS

Load in Tons

Height Size in inches
in ft.
6 × 6 6 × 8 8 × 8 8 × 12 12 × 12 12 × 16 16 × 16
6 2 3 4 5 6 7 9
8 1½ 2½ 3½ 4¾ 5½ 6 8
10 1 2 3 5 5½ 6 7

STRESSES FOR STRUCTURAL TIMBERS

WORKING UNIT STRESSES USED IN DRY LOCATIONS

Bending Compression

Stress in Horizontal Parallel to Perpen-
extreme shear grain "Short dicular
Species of fibre stress Columns" to grain
Timber Lbs. sq.in. Lbs. sq.in. Lbs. sq.in. Lbs. sq.in.

*Fir, Douglas
Dense grade 1,600 100 1,200 350
Sound grade 1,300 85 900 300
Hemlock, eastern 1,000 70 700 300
Hemlock, western 1,300 75 900 300
Oak 1,400 125 900 400
Pine, eastern white 900 80 700 250
Pine, Norway 1,100 85 800 300
*Pine, southern yellow
Dense grade 1,600 125 1,209 350
Sound grade 1,300 85 900 300
Spruce 900 70 600 200
Tamarack 1,200 95 900 350

* NOTE: The safe working stresses given in this table are for
timbers with defects limited according to the sections on defects
in the rules of the Southern Pine Association for Select Structural
Material. "Dense" southern yellow pine and "dense" Douglas fir
should also conform to the other requirements of this rule. "Sound"
southern yellow pine and "sound" Douglas fir require no additional
qualifications, whereas the other species should, in addition to
being graded for defects, have all pieces of exceptionally low
density for the species excluded.

This table gives working unit stresses for structural timbers
used in dry locations, and is compiled in the main from material
furnished by the Forest Products Laboratory, Madison, Wis.

TABLE OF BRICK WALL CONTENTS IN NUMBER OF BRICKS

Seven Bricks to Each Sq. Ft. of Wall Surface

No. of
sq ft. Thickness
of wall
4" 8" 12" 16" 20" 24"
1 7 15 23 30 38 45
2 15 30 45 60 75 90
3 23 45 68 90 113 135
4 30 60 90 120 150 180
5 38 75 113 150 188 225
6 45 90 135 180 225 270
7 53 105 158 210 263 315
8 60 120 180 240 300 360
9 68 135 203 270 338 405
10 75 150 225 300 375 450
20 150 300 450 600 750 900
30 225 450 675 900 1,125 1,350
40 300 600 900 1,200 1,500 1,800
50 375 750 1,125 1,500 1,875 2,250
60 450 900 1,350 1,800 2,250 2,700
70 525 1,050 1,575 2,100 2,625 3,150
80 600 1,200 1,800 2,400 3,000 3,600
90 675 1,350 2,025 2,700 3,375 4,050
100 750 1,500 2,250 3,000 3,750 4,500

_Example_--Determine the number of bricks in a wall 12" × 18' × 60'.

_Solution_--The wall contains a surface area of 1,080 sq. ft. By
the table 100 sq. ft. contains 2,250 bricks, then 1,000 sq. ft. will
contain 22,500 bricks. 80 sq. ft. will contain, by the table, 1,800
bricks, making a total of 24,300 bricks.