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Root

Water Trough

Bill of Material 2 pieces yellow pine i|xi2-x5:o"Sides

1 - i|"xi2"x5lo"Bofiom

i|"xioix 19" Ends 2"x4"xis" Legs 2"X4"Xl9"Cr05S p'c'5. 2" x4'X4'-2" Braces fba i6d.and ilb. lod. Common nails Small quantity white lead and paint

5" Metal target

Washer Thumb nut

Cleat J'Wx/o" Tripod table fxa'xio"

Plane Table and Leveling Rod

The dotted lines show the position of the rafter or pitch of roof.

Problem:

Given the span of a buildinq; as, e.io.12, i4,i6. or i©ft. and the pitch of roof desired,- os,^, ¿,i, ¿.¿or^to take a piece of 2"x4* or^'xe-and lai^ out the rafter

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15-24-J Pitchr

Use 12* for run

and wfor rise

12"

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Use the square as many times as there are feet in the ran iz'Run -

PlumbCut 12*

The span of a building is the distance from the outside edge of one side wall plate to the outs/de edge of the opposite wall plate. The run is one half of the s^an. The rise is the vertical distance from the of the plate to the ridge.

SAW FITTING

There are many cross cut saws of varying designs in use in the lumbering industry, but for general farm use selection may be made from the four illustrated in the drawing. Figures A, B, and C are of saws suited for general use. Fig. D shows a shape of tooth better suited for knotty lumber.

The tools required for cross-cut-saw fitting are as follows:

1 cross-cut-saw tool which consists of a jointer, a raker-tooth gauge and a tooth set gauge. 1 saw set. Several flat files.

The essential features of a well fitted saw are:

1. All teeth must be of the same length and all points come to the same plane so that each tooth will do the same work as each other tooth.

2. All rakers must be not less, than 1-100 nor more than 1-32 of an inch shorter than the cutting teeth and must be filed to sharp chisel-shaped edges.

3. All teeth must be filed to a sharp point.

4. All teeth must be uniformly set so that the saw draws freely thru the wood.

JOINTING, SETTING AND FILING A GROSS CUT SAW

There are four operations in bringing a cross cut saw to a good cutting condition: (1) jointing; (2) filing down the rakers; (3) setting the cutting teeth; (4) filing the rakers and cutting teeth.

A saw is jointed by holding the file in the saw tool as shown in Fig. 29 and, holding the file on the teeth and the saw tool tightly against the side of the saw, drawing the file lengthwise over the saw until all teeth and rakers have been touched.

To file down the rakers the saw tool is placed on the teeth so that a pair of rakers projects up thru the slot in the tool. Fig. 30. All that part of the rakers which projects up thru the slot is filed off so that the points of the rakers will be below the points of the cutting teeth. The distance which the rakers are below the points of the cutting teeth may be varied according to the kind of wood which the saw is to be used for. The rakers should be not less than 1-100 of an inch nor more than 1-32 of an inch shorter than the teeth. Soft woods may have a greater, distance than hard woods. If the saw has a tendency to jump when in use the rakers are too long and need to be filed down and sharpened.

About i/i" of the point of each tooth is set. This consists of placing the saw set on a tooth and pressing the tooth out so as to make the saw kerf wider than the blade of the saw. Begin at one end and set every other tooth to one side, then reverse the saw and set the other teeth in the opposite direction. The amount of set to give a saw is determined by the use that the saw is to have. Green and wet lumber require more set than dry lumber. The set of the saw is regulated by the set screw at the bottom of the saw set.

One-Man,Cross-Cut

• |A

Two-Man, Cross-Cut ng teeth arranged in for general work.

5.

Two-nan. Bevel for aenerc o o o fc / \ Cutting teeth

3l work. Fiq.G

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Two-Mari imooth sav i/^/N

i. Round point for jinq in knotty lumber

) f,q E: j A Buck saw blade \

Crosscut 5aw teeth

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Rip Saw Teeth jmmmmtv blade i£rt,tonque 6-jf 60* " & » iog

For desired angles set T 12*- b 1 a de i 2",t ongue 2 5e

4a- " 12", " 13® ©2

bevel on steel square b 1 ade 6",tongue ajf

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SAWS and SAW FITTING

The rakers are filed to a chisel point. Effort should be made to keep all of the rakers the same shape and size and the filing regulated with this in mind. Since the purpose of the rakers is not to cut but to draw the cut particles of wood lengthwise of the saw kerf and out, they should be kept true and straight and may be filed from one side of the saw. The file is held straight across the saw. Great care must be taken not to bring either the rakers or the cutting teeth below the surface to which they have been jointed as that will render them out of cutting or raking service.

To file the teeth, the saw is placed low in the clamp so as to hold it firmly and minimize the vibration. All the teeth projecting away from the filer are filed from one side. Both edges of the tooth are filed the same because the saw is to cut both ways. The file is held at an angle as shown by the points of the cutting teeth in Fig. C, and by forward strokes of the file the tooth is brought to a point. When all the teeth projecting to one side have been filed the saw is reversed and the teeth projecting in the opposite direction are filed in the same way.

If a saw has been used extensively and filed so that the teeth are short it should be gummed. This consists of grinding a slot down into the blade between the teeth with a thin emery grinder.

When not in use, the blade of the saw should be covered with a coat of oil to prevent rusting. If a saw has become rusty it should not be cleaned with coarse emery cloth or coarse sand paper or other substance or preparation that will scratch the surface of the metal. No. 0 or 00 sand paper or 00 emery cloth or kerosene oil may be used.

The tools required for fitting hand saws are:

1 flat file.

Several slim taper triangular files—size determined by the fineness of saw.

1 saw set.

The first point to observe in fitting a saw is to make sure that the points of all teeth are in the same plane, so that no tooth projects out farther than any other. This is accomplished by running the side of a flat file lengthwise over the teeth and is called jointing the saw. The file is

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