Using the Screwdriver

Where several screws are to be driven, particularly large screws, a screw-driver bit in a brace makes for faster and easier work. Such a bit is simply a screw driver that, instead of having a handle, has a square tapered end that fits into a brace. Care should be exercised when using the screw-driver bit to keep it from slipping out of the slot and marring the wood and possibly the screw head also. The bit is more easily kept in the slot if the ratchet on the brace is used or if the crank is backed up slightly every quarter or half turn.

GLUE AND GLUING

8fi TTinHfi nf fJltiA_Tli^r*» «r^ twn Fl°- 86.—Driving screws with

Kjnas ot Wue. mere arc two {he screw_,rivcr bit. Backing th«

general kinds of glue: hot glue and cold crank a little every quarter or half glue. The hot kind must be heated hel',if ke0? the bit in the 5Crew carefully and applied hot, while cold glue may be bought in cans ready to apply. Ready prepared cold glue is probably better for the farm shop because of the greater convenience.

Glue should be used in accordance with directions on the container. In cold weather it is generally best to warm the glue by placing it in hot water for a while before using. If the glue is too thick, owing to evaporation from a can that was not tightly sealed, it should be thinned with alcohol or other thinning material that may be recommended in the directions on the can.

87. Applying Glue.—Be sure that the parts to be glued fit properly, and that all clamps, material, and equipment are in readiness before applying the glue. The glue should be applied thoroughly to all parts and brushed or otherwise worked well into the pores and grain of the wood. It is a common tendency of beginners to apply too much glue. If the joint is a movable one, rub one piece back and forth over the other to thoroughly distribute the glue and work it into the pores.

88. Clamping Pieces Together.—Once the glue Is applied, the pieces should be securely clamped together and allowed to stand until the glue has hardened. If regular cabinetmaker's clamps are not available, clamps may be improvised by using the vise, or the bench top and wedges, or by twisting wire or rope.

If two or more boards are to be glued edge to edge to form a wider piece, the edges must be very carefully jointed, that is, made straight and square with the working surfaces of the boards. If the boards are to be planed after gluing, they must be so placed that the grain will run the same way in all of them. If the grain should run one way in one board, and the opposite in the adjoining one, it would be impossible to plane one smooth without roughing up the other.

Glued joints are general^ reinforced by the use of dowels or corrugated fasteners, or both.

89. Doweling.—A doweled joint is one in which the pieces are held together by round wooden pins called dowels. Figure 87 illustrates a

Fig. 87.—A doweled joint ready to be slued and assembled.

typical doweled joint. Dowels may be bought, or they may be made by splitting some straight-grained wood and planing or whittling roughly to size, after which the pieces are driven through a round hole in a piece of steel called a dowel plate. The holes in a dowel plate are tapered slightly, and the wooden pieces are driven through the small end of the hole first-to prevent binding. It is a good practice to drive the piece of wood first through an oversize hole in the dowel plate and finally through a hole of the required size.

A dowel plate can be easily made by drilling holes of the desired size, usually to Yi in., in a piece of steel and reaming them slightly with a tapered reamer or with a round file if the work is done carefully. Care must be taken in reaming not to enlarge the hole 011 one side of the plate.

90. Locating and Boring Dowel Holes.—In using dowels it is very important that the holes be accurately located and bored so as to match, and that the holes be bored perpendicular to the surface. If two boards are to be fastened edge to edge by doweling, they should be clamped together in the vise with the edges to be joined even and with the working surfaces out. The dowel holes are then located by squaring across the edges with a try square and a knife, and by gaging about half the thickness of the pieces from the working surfaces.

Dowel holes are then bored the same size as the dowels. They generally need not be over 1 in. deep. The mouth of the holes should be countersunk slightly. The dowels should have their ends trimmed or pointed very slightly, and each one should have a small groove cut lengthwise in it with a knife or saw, to allow the air and exccss glue to escape when it is forced into place.

Questions

68. (a) Name two different kinds of nai] hammers. (ft) What arc the advantage* of the two kinds? (c) How is the size of a hammer designated?

69. (a) How are nails made? (ft) Name and describe a few of the more common kind« of nails, (c) How is the size of nails designated?

70. (a) Explain and be able to demonstrate just how to start a nail and drive it properly. (ft) What trouble is likely to be encountered if dirt is allowed to get on the striking face of the hammer?

71- (a) What are some of the common causes of splitting when nails are driven? (ft) How may nails be treated to prevent splitting thin boards?

72. (a) Explain and be able to demonstrate juat how to pull nails with a hammer. (6) What is the purpose of using blocks under the hammer head when pulling nails? (c) How may a nail be pulled when the hammer claws cannot be slipped under the nail head?

73. What points should he observed in locating nails in a nailed joint?

74. State a principle to be observed in clinching nails to give increased holding power.

75. (1a) What is toenailing? (ft) What difficulties arc likely to be encountered in toenailing if the workman is not careful, and how may these difficulties be prevented?

76. (a) What is meant by "setting" nails? (ft) Describe and be able to demonstrate the method of holding a nail set on a nail.

77. (a) What is draw nailing? (ft) Give an example of its use.

78. (a) Give examples of the use of corrugated fasteners. (b) What precaution should bo observed in driving them?

79. (a) Name common kinds of wood screws, classified according to shape of head and finish. (6) How is the size of wood screws designated?

80. (a) What is a lag screw? (b) How is the size of lag screws designated?

81. (a) How large a hole should be drilled through the top or first piece when fastening two pieces of wood together? (6) How large a hole should be drilled into the second piece, and how deep should it be drilled?

82. (a) Why is it important, to start a drill in an awl hole? (6) Describe and be able to demonstrate different ways of easily locating and drilling the pilot holes in the second board to receive screws.

83. (a) What kind of screws require countersinking? (6) What is a common mistake in countersinking, and how may it be prevented? (c) What is the difference between countersinking and countcrl>oring?

84. (a) What troubles are likely to be encountered in using a screw driver that is poorly fitted or of wrong size? (b) Explain and be able to demonstrate a good method of holding and'using a screw driver, (c) What should be done in case a screw turns too hard?

86. (a) What advantages has a screw-driver bit used in a brace over an ordinary screw driver? (b) Why is it better to use the ratchet device on the brace and advance the screw by part turns rather than complete continuous turns?

86. (a) What kind of glue is generally best for the farm shop? (6) What material may be used for thinning glue?

87. (a) What preparations should be made before applying glue? (&) How may glue be worked well into the pores of wood?

88. (a) In the absence of cabinetmaker's clamps, how may boards be held together after glue is applied? (6) What precautions should be taken in assembling boards so they may be planed after gluing?

89. (a) What is a dowel? (6) How may dowels be made? (c) How may a dowel plate be made in the farm shop?

90. (a) Describe and be able to demonstrate the process of locating and boring holes for dowels. (6) What treatment should dowels receive before glue is applied and before they are inserted in the holes? Why?

References

Hjortii: "Basic Woodworking Processes/'

Brown and Tustison: "Instructional Units in Hand Woodwork." Griffith: "Essentials of Woodworking." Smith. Robert H.: "Agricultural Mechanics."

Educational charts and pamphlets, Stanley Tool Works, New Britain, Conn.

CHAPTER VII

Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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