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Lumber Measure

Formerly sawlogs were sawed into boards without being turned. The left side of the illustration shows this method of sawing lumber. Valuable woods are now largely quarter sawed, the log being divided lengthwise into four quarters and the boards being sawed alternately from the sides of each quarter as

shown in the upper right-hand quarter, or diagonally as shown in the lower right-hand quarter.

This method of quarter sawing is partly for the purpose of preventing the warping of the wood and partly to distribute the graining in the wood more evenly across the boards.

Show by the above diagram how the graining (made by the rings of growth) is better distributed in the sections that are quarter sawed.

Lumber is measured by what is known as the board foot. A board footi is a piece of lumber one foot square and one inch thick. Any lumber less than an inch thick is usually considered as an inch thick in computing the number of board feet.

A board 6 feet long, 1 foot wide and 1 inch thick contains 6 board feet. A board 6 feet long, 6 inches wide and 1 inch thick contains 3 board feet. A piece of timber 6 feet long, 1 foot wide and 4 inches thick contains 24 board feet.

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The number of board feet in a piece of lumber is equal to the number of square feet in one of its surfaces multiplied by the number of inches in thickness.

1The teacher should be provided with a board 1 foot square and 1 inch thick to give the pupils a concrete conception of a board foot.

Exercise 10

1. Find the number of board feet in a board 14 feet long, 6 inches broad and 1 inch thick.

2. How many board feet are there in a plank 10 feet long, 11 feet broad and 2 inches thick.

3. A sill 13 feet long, 6 inches wide and 6 inches thick contains how many board feet?

4. How many board feet are there in 20 planks 12 feet long, 1 foot wide and inch thick?

Lumber in large amounts is reckoned in thousands of board feet. "3000 feet” of lumber or "3 M ft.," as it is usually written, means three thousand board feet.

5. What is the cost of 5 M ft. of hardwood flooring at $80 per M ft.?

6. Find the cost of 5 M ft. of barn siding at $40 per M ft. In stating the dimensions of pieces of lumber it is customary to use the sign' to indicate feet and the sign " to indicate inches.

7. How many board feet are there in a sill 10' X 8" X 8"? Find the number of board feet in the following: 8. 40 boards 12' X 12" x 2". 13. 60 joists 20' X 8" X 2". 9. 50 boards 16' X 6" X1". 14. 40 sills 20' X 12" X 10". 10. 25 boards 16' X 10" X 2". 15. 25 posts 12' X 12" X 10". 11. 20 boards 16'X4" X ". 16. 60 sleepers 20' X 10" X3". 12. 20 studding 12' X 4"x2". 17. 25 planks 12' X1'X2". Find the cost of the following lumber: 18. 25 boards 16'X8" X 1" at $90 per M. 19. 16 boards 12' X 15" X 11" at $120 per M. 20. 35 boards 15'X6" X" at $92.50 per M.

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Exercise 11. Carpentering Problems

When boards have tongues and grooves cut in them for flooring, part of the width of the board is wasted. In addition there is also some waste in squaring up the ends and sawing the boards to fit the space where they are used. For these reasons carpenters usually allow į of the amount of lumber

ordered for waste. 1. What will it cost for a maple floor 16'x30' at $140 per M, allowing i extra for waste?

Solution: 16X30X1 (the thickness) =480, the number of actual board feet needed. But extra must be allowed for waste in grooving the boards and laying the floor. 1 of 480=120. 480+120=600. 600 board feet =.600 M ft. .6 M ft. at $140 per M=.6 X $140 =$84, the cost of the flooring.

2. What will it cost for a floor 30'X25' at $130 per M, allowing for waste?

3. Find the cost of laying a plank walk 3 feet wide, 90 feet long and 14 inches thick at $75 per M.

4. A floor of a veranda 8' x 20' is laid of stock 11" thick. How many feet of flooring are required, allowing 5 feet extra for squaring the ends?

5. The Homer Club erected a backstop for their baseball diamond 10' X 24'. How many board feet of lumber 1" thick was needed for the siding?

6. It also required 6 pieces of 2" X4", 10' long, for uprights and 6 pieces of 2" X 4", 73' long, for braces. How many feet of 2" X4" were needed?

7. How much did the lumber for the backstop cost at $85

per M?

8. Find the cost of flooring a barn 30' X 24' with 2" planks at $75 per M.

Exercise 12. Shop Problems Use the following price list in solving these problems: Pine 12 cents. Gumwood 18 cents. Quartered oak 30 cents.

1. Find the cost of the following taboret made of quartered oak: Top, 16" X 16"X1"; bottom, 12" X 12"X1"; four legs, 24"X3"X1".

2. Find the cost of this footstool: Top, pine, 14" X 72"X1"; sides, gum, 131" X22" X9"; 4 legs, gum, 1ż" X1]" X6". Imitation leather 25 cents; tacks 10 cents; screws 10 cents.

3. How much will this frame for a sign, made of pine, cost: 2 pieces 8' X 2"X1"; 2 pieces 1}' X2"X1"?

4. Compute the cost of the gum lumber in the following candlestick: 1 piece 2"x2" XZ"; 1 piece 1]" X1]" X2"; i piece 41" X4"X1"; 1 piece 3" X2"".

6. Find the cost of quartered oak for a pedestal: 2 pieces 13" X3"X1"; 4 pieces 21" 22"X1"; 2 pieces 81" X 82"X1"; 2 pieces 32" X32" X ".

6. Find the cost of quartered oak for this cabinet for a wireless receiving set: 1 piece 182"X11" X2"; 2 pieces 10" X 32" X2"; 1 piece 172"X3" X 2".

7. How much will this lumber cost for a music cabinet: quartered oak, 3 boards 36" X14" "; 1 board 16" X 17"; 2 boards 3"X131"; 6 boards 11" X 131"; pine, 2 boards 132"X 9{"; 10 boards 12" X 153".

8. Find the cost of the following wood: 2 boards 14" x 24" xì" at 12 cents a board foot; 2 boards 6" X6" xż" at 12 cents a board foot; 1 board 14" X74" X 21" at 10 cents a board foot.

9. Find the cost of the following taboret made of pine: 2 pieces 16" X 16" **"; 2 pieces 4" X 16" "; 2 pieces 32" X 19" X".

Exercise 13. Measuring Land

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8

11

12

31

32

6

In most parts of our country the 5 43 2

land is laid off in townships. These 7 9 10

townships are 6 miles square. 18 | | 17 16 15 14 13 1. How many square miles are

there in a township? 19 20 21 22 23 24 |

Each square mile in a township 30 29 28 27 26 | 25

is called a section. The sections of 33 34 35 36 each township are numbered in the A Congressional Township

manner shown in the figure.

2. Draw a plan of a township showing the 36 sections and number them in the correct way without referring to the diagram in the book.

Each section or square mile is divided into quarter-sections for convenience in de- N. W. N.E.

QR. QR. scribing small farms. The quarter-sections are not numbered, but are called the North

S.W. SE. east, Northwest, Southeast and Southwest

QR. QR. quarters. 3. How many acres are there in a sec

A Section, or

Square Mile tion? How many in a quarter-section?

4. An 80-acre farm is what part of a quarter-section? Of a section?

Of

6. A 40-acre farm is what part of a quarter-section? a section?

6. Roads are generally built to follow section lines. How far is it by section roads from the lower right-hand corner of section 26 to the upper left-hand corner of section 16? Show at least 3 ways in which one could go by road from the first to the second point.

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