This section is from the book "Modern Carpentry And Building", by W. A. Sylvester. Also available from Amazon: Modern Carpentry And Building.
Length. | 2 in. | 3 in. | 4 in. | 5 in. | 6 in. | 7in. | 8 in. | 9 in. | 10 in. | 11 in. | 12 in. | 13 in. | 14 in. | 15 in. | |
5 | ft. | 12 .4 | 44 | 102 | 184 | 288 | 414 | 500 | 728 | 910 | 1,120 | 1,354 | - | _ | _ |
6 | ,, | 9.4 | 36 | 88 | 104 | 204 | 380 | 532 | 698 | 884 | 1,082 | 1,320 | 1,570 | - | - |
7 | ,, | 7.2 | 30 | 70 | 146 | 242 | 360. | 502 | 600 | 850 | 1,056 | 1,282 | 1,530 | 1,798 | 2,086 |
8 | ,, | - | 24 | 66 | 130 | 218 | 332 | 470 | 630 | 812 | 1,016 | 1,240 | 1,486 | 1,754 | 2,040 |
9 | ,, | - | 20 | 56 | 114 | 198 | 306 | 440 | 596 | 774 | 974 | 1,196 | 1,440 | 1,706 | 1,092 |
10 | ,, | - | 18 | 48 | 102 | 180 | 282 | 410 | 560 | 739 | 932 | 1,152 | 1.302 | 1,050 | 1,040 |
12 | ,, | - | - | 38 | 80 | 136 | 238 | 354 | 494 | 658 | 846 | 1,050 | 1,292 | 1,550 | 1,828 |
14 | ,, | - | - | 28 | 64 | 122 | 200 | 304 | 432 | 556 | 774 | 900 | 1,192 | 1.440 | 1,712 |
16 | ,, | - | - | - | 52 | 100 | 170 | 202 | 378 | 520 | 686 | 878 | 1,004 | 1,332 | 1,500 |
18 | ,, | - | - | - | 44 | 84 | 144 | 220 | 332 | 462 | 616 | 790 | 1,000 | 1,228 | 1,482 |
20 | ,, | - | - | - | - | 72 | 124 | 196 | 292 | 410 | 552 | 720 | 912 | 1,130 | 1,372 |
For tubes or hollow columns, subtract the weight that may be borne by a column of the size of the internal diameter of the tube or column. The thickness of metal should not be less than one-twelfth the diameter.
 
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