Machinery's Handbook, 31st Edition
Wood 385 the listed quality requirement for the processes. For example, 62 percent of the black walnut pieces planed came out perfect, but only 34 percent of the pieces run on the shaper achieved good to excellent results. Table 3. Machinability and Related Properties of Various Domestic Hardwoods
Planing
Shaping
Turning
Boring
Mortising
Sanding
Quality Required
Fair to Excellent
Good to Excellent
Fair to Excellent
Good to Excellent
Good to Excellent
Type of Wood
Perfect
Alder, red
61 75 26 64 83 63 47 80 74 21 33 74 76 65 52 54 41 91 87 88 51 22 80 48 55 62 52 70
20 55 10 7 24 57 22 80 28 13 10 3 20 27 56 72 25 28 35 40 28 12 39 32 52 34 13 5
88 79 65 68 90 80 … 88 87 70 65 77 84 79 82 8 76 84 85 89 86 85 81 75 79 91 58 81
64 94 78 76 99 97 …
52 58 60 51 92 97 …
… 75 … 17 49 34 … … 64 19 66 … 80 37 … 38 37 81 83 … 23 21 … 21 34 … 24
Ash Aspen Beech Birch
Basswood
Birch, paper Cherry, black Chestnut Cottonwood Elm, soft Hackberry Hickory Magnolia Maple, bigleaf Maple, hard Maple, soft Oak, red Oak, white Sweetgum Sycamore Tanoak Tupelo, black Tupelo, water Walnut, black Yellow-poplar Willow Pecan
100 91 70 94 99 100 71 100
100 70 52 75
72 98 32 80 95 34 95 99 98 53 96
99 80 99 95
100 92 98 100 82 62 71 100
100 24 33 98
24 63
87 19 The data above represent the percentage of pieces attempted that meet the quality requirement listed. Nominal and Minimum Sizes of Sawn Lumber
Thickness (inches)
Face Widths (inches)
Type of Lumber
Nominal, T n
Dry
Green
Nominal, W n
Dry
Green
2 to 4 5 to 7 8 to 16 2 to 4 5 to 6 8 to 16
1
W n − 7 ⁄ 16 W n − 3 ⁄ 8 W n − 1 ⁄ 2 W n − 7 ⁄ 16 W n − 3 ⁄ 8 W n − 1 ⁄ 2
W n − 1 ⁄ 2 W n − 1 ⁄ 2 W n − 3 ⁄ 4 W n − 1 ⁄ 2 W n − 1 ⁄ 2 W n − 3 ⁄ 4
25 ⁄ 32
3 ⁄ 4
Boards
1
1 1 ⁄ 4 1 1 ⁄ 2
1 1 ⁄ 32 1 9 ⁄ 32 1 9 ⁄ 16 2 1 ⁄ 16 2 9 ⁄ 16 3 1 ⁄ 16 3 9 ⁄ 16 4 1 ⁄ 16
1 1 ⁄ 4 1 1 ⁄ 2
2
2
2 1 ⁄ 2
Dimension
3
2 1 ⁄ 2
Lumber
3
… … …
… … … …
… … …
3 1 ⁄ 2
4
3 1 ⁄ 2
4
4 1 ⁄ 2
Timbers W n − 1 ⁄ 2 Source: National Forest Products Association: Design Values for Wood Construction . Moisture content: dry lumber ≤ 19%; green lumber > 19%. Dimension lumber refers to lumber 2 to 4 inches thick (nominal) and 2 inches or greater in width. Timbers refers to lumber of approximately square cross section, 5 3 5 inches or larger, and a width no more than 2 inches greater than the thickness. 5 and up … T n − 1 ⁄ 2 5 and up
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