Bench work in wood; a course of study and practice designed for the use of schools and colleges

Preface

TO avoid confusion, the subject herein treated is considered in three divisions. Part I. contains the essential facts concerning common bench tools for wood ; it describes their action, explains their adjustments, and shows how they may be kept in order. Part II. presents a course of practice by which ability to use the tools may be acquired ; and Part III. discusses such forms and adaptations of joints as will meet the requirements of ordinary construction. It is not expected that the student will complete Part

I. before entering upon Part II., or that he will finish Part

II. before commencing Part III. He will find greater profit in using them together. For example, a shop exercise involving the chisel (Part II.) should be accompanied or preceded by a study of the chisel (Part I.) ; again, the various forms of mortise-and-tenon joints (Part III.) will be better understood and more easily remembered, if considered during the time when types of such joints are under construction in the shops (Part II.). In the writer's experience with classes of students, one hour has been given to class-room work for every five hours given to shop work. By this apportionment, Parts I. and III. can be mastered in the class-room while Part II. is in progress in the shops.

The equipment necessary for carrying out the course of iv

PREFACE.

practice given in Part II. is much less expensive than may at first appear. Besides a bench, a pair of trestles, and a bench-hook, the following-named tools are needed : — i 2-ft. Rule, i Framing-Square, i 7-inch Try-Square, i 8-inch Bevel. 2 8-inch Marking-Gauges, i Chalk-Line, with Chalk, i Lead-Pencil, i Scriber.

Firmer-Chisels, i each, ^", \", and i

Gouges, i each, i 22-inch Cross-cutting-Saw, teeth.

i 24-inch Ripping-Saw, 6 teeth.

1 10-inch Back-Saw.

1 8-inch Drawing- Knife.

1 Fore-Plane.

1 Jack-Plane.

1 Smooth-Plane.

1 Set Auger-Bits, J" to 1" by

i6ths.

1 Bit-Brace.

1 Brad-Awl.

1 Carpenter's Hammer.

1 Mallet.

1 Nail-Set.

1 Oilstone.

1 pair 8-inch Dividers.

1 pair I -inch Matching- Planes.

1 T 3 g-inch Beading-Plane.

1 i-inch Beading-Plane.

1 Plow.

1 Hand-Scraper.

\ doz. Quill Bits, assorted from |"

down.

I Miter-Box.

I Grindstone.

if provision is to be made for more than one student, the items printed in small type need not be duplicated. One set of these will suffice for any number less than thirty.

The writer is indebted to Mr. M. Golden, of the School of Mechanics and Engineering, Purdue University, for the execution of many of the drawings and for valuable suggestions.

Purdue University,

Lafayette, Ind.

Preface To Second Edition

In the preparation of this edition the text has been revised and a new section dealing with timber and its preparation for use has been added. This appears as Part IV and, in common with Parts I and III, is designed for use in connection with the course of practice outlined in Part II. Use has been made of Snow's " Principal Species of Wood," from which several of the illustrations of Part IV have been taken or adapted, and also of certain publications of the United States government, especially those prepared by Professor C. S. Sargent and Dr. B. E. Fernow.

Contents

INTRODUCTION. — INTERPRETATION OF MECHANICAL DRAWINGS.

PAGES

[. Mechanical Drawings Defined. — 2. Plans. — 3. Elevations. — 4. Method of showing Parts Obscured from Sight. — 5. Sections. Section Lines. Cross-hatching. Incomplete Sections. — 6. Broken Drawings. — 7. Scale. — 8. Dimensions. Dimension Lines, 1-6

Part I. — Bench Tools

9. Bench. — 10. Bench-Stop. — n. Vise. — 12. Bench-Hook. —

13. Trestles 7-9

Measuring and Lining Appliances.

14. Early Standards of Length. — 15. English Standard Yard. — 16. United States Standard of Length. — 17. The Troughton Scale.

— 18. Rules. — 19. Framing-Square. — 20. Board-measure Table.

— 21. Brace-measure Table. — 22. Try-Square. — 23. Bevel. — 24. "Miter-Square." — 25. Try-and-" Miter " Square. — 26. Dividers. — 27. Scribing with Dividers. — 28. Combining Square and Rule. — 29. Combining Square and Bevel. — 30. Setting the Bevel at an Angle of 60 Degrees. — 31. Setting the Bevel at any Given Angle. — 32. Marking-Gauge. — ^3- Mortise-Gauge. -— 34. Panel-Gauge. — 35. Cutting-Gauge. — 36. Chalk-Line.

Vlll CONTENTS.

Chisels and Chisel-like Tools.

39. Firmer-Chisels. — 40. Framing-Chisels. — 41. Corner-Chisels. — 42. Gouges. — 43. Chisel Handles. — 44. Drawing-Knife. — 45. Action of Cutting Wedges. — 46. Angle of Cutting Wedge in Chisel and Gouge. — 47. Grinding. — 48. Whetting , . . 20-26

Saws.

49. Efficiency. — 50. Form. — 51. Set. — 52. Size of Teeth. — 53. Ripping-Saw and Cross-Cutting-Saw Defined. — 54. Teeth of Ripping-Saws. — 55. Teeth of Cross-Cutting-Saws. — 56. Back- Saw. — 57. Compass-Saw , , 26-36

Appliances for Filing and Setting Saws.

58. Files. — 59. Sets for Bending the Tooth. — 60. Sets for Swedging

the Tooth. — 61. Clamps 36-38

Saw Filing and Setting. 62 Top-Jointing. — 63. Setting. — 64. Filing. — 65. Side- Jointing, 39-41

Planes and Plane-like Tools.

66. Description of Planes. — 67. Length of Stock. — 68. Plane-Iron. Angle of Cutting Wedge. — 69. Outline of Cutting Edge. — 70. Use of Different Bench Planes. — 71. Action of Smooth- Plane and Fore- Plane Compared. — 72. The Cap. — 73. Narrowness of Mouth. — 74. Adjusting the Iron. — 75. Jointing a Plane. — 76. Iron Planes. — 77. Planes of Wood and Iron Combined. — 78. Circular-Planes. — 79. Block-Planes. — 80. Spokeshaves. — 81. Rabbeting-Planes. — 82. Matching-Planes. — 83. Hollows and Rounds. — 84. Beading- Planes. — 85. Plows. — 86. Combination Planes. — 87. Scrapers 4 I_ 5 2

Boring Tools.

88. Augers. — 89. Auger-Bits. — 90. Sharpening Augers and Auger- Bits. — 91. Center-Bits. — 92. Expansive Bits. — 93. Small Bits. — 94. Bit-Braces. — 95. Angular Bit-Stock. — 96. Automatic Boring Tool 53—59

CONTENTS. IX

Miscellaneous Tools.

97. Winding-Sticks. — 98. Hand Screw-Driver. — 99. Brace Screw- Driver. — 100. Hammer. — 101. Hatchet. — 102. Mallet. — 103. Sana-Paper. — 104. Wooden Miter-Box. — 105. Iron Miter-Box. — 106. Clamps. — 107. Grindstone. — 108. Use of Water on a Grindstone. — 109. Truing a Grindstone. — no. Truing Devices for Grindstones. — in. Oilstones. — 112. Oil for Oilstones. — 113. Form of Oilstones. — 114. Oilstone Slips. — 115. Truing an Oilstone 59-69

Part II. — Bench Work

[16. Good Lines a Necessity. — 117. Location of Points. — 118.

Jointed Face. — 119. Working- Face 71—73

EXERCISE No. 1. — Measuring and Lining.

120. Material. — 121. Spacing: Pencil and Rule. — 122. Lining: Pencil, and Framing-Square. — 123. Chalk- Lining. — 124. Lining: Pencil, and Try-Square. — 125. Lining: Pencil and Bevel. — 126. "Gauging" Lines: Pencil and Rule. — 127. Spacing: Scriber and Rule. — 128. Lining: Scriber, and Try-Square. 129. Lining: Scriber and Bevel. — 130. Gauge-Lining. — 131. Lining for Exercise No. 3 73—79

EXERCISE No. 2. — Chiseling and Gouging.

132. Chiseling by Hand. — 133. Chiseling by Use of Mallet. — 134.

Gouging 80-83

EXERCISE No. 3. — Sawing.

135. Handling the Saw. — 136. Guiding the Saw. — 137. Correcting the Angle of the Cut. — 138. Rip-Sawing. — 139. Cross-cutting 83-86

EXERCISE No. 4. — Planing.

140. Handling the Plane. — 141. Why a Plane Clogs. — 142. Jointing. — 143. Planing to a Square. — 144. Method of Performing

X CONTENTS.

PAGES

Similar Operations. — 145. Smooth Surfaces. — 146. Sand- Papering 86-91

EXERCISE No. 5. — Box.

147. Jointing to Width. — 148. Sawing to Length. — 149. Nailing. — 150. Hammer Marks. — 151. Setting Nails. — 152. Withdrawing Nails. — 153. Fastening the Box Bottom. Finishing the Box. — 154. Planing End Grain 91-96

EXERCISE No. 6. — Bench-Hook. 155. Lining and Sawing. — 156. Using the Auger-Bit .... 96-98

EXERCISE No. 7. — Halved Splice.

157. Lining. — 158. Value of Working-Face Illustrated. — 159. Cutting the Joint. — 160. Sawing a Fit. — 161. Toeing Nails . 99-102

EXERCISE No. 8. — Splayed Splice. 162. Lining. — 163. Cutting and Finishing the Joint .... 103, 104

EXERCISE No. 9 — Simple Mortise-and-Tenon Joint.

164. Lining. — 165. Cutting the Mortise. — 166. Cutting the Tenon.

167. Making a Pin. — 168. Drawboring 104-110

EXERCISE No. 10. — Keyed Mortise-and-Tenon Joint. 169. Lining and Cutting. — 170. Key no, in

EXERCISE No. ii. — Plain Dovetail.

171. Lining and Cutting. -=- 1 72. Gluing. — 173. Short Method of

Lining and Cutting the Joint . . . 1 1 2, 1 13

EXERCISE No. 12. — Lap Dovetail. 174. Lining and Cutting 114. i J 5

CONTENTS. XI

PAGES

EXERCISE No. 13.— Blind Dovetail. 175. Lining and Cutting. — 176. A Modified Form of the Joint . 115-117

EXERCISE No. 14. — Frame and Panel.

177. Panel Door Described. — 17S. Making the Joint between Stile and Rail. — 179. Cutting Chamfers. — 180. Keying the Joint. — 181. Finishing the Panel. Fastening Panel to Frame. — 182. Inserting Screws. — 183. Using the Brad- Awl . . 117-121

EXERCISE No. 15.— Frame and Panel.

184. Making Joint between Stile and Rail. — 185. Plowing. — 186.

Beading. — 187. Forming the Panel 121-124

Part III. — Elements Of Wood Con- Struction. Carpentry

188. Work of Carpenter and Joiner Compared. — 189. Congressional, Tensional, and Transverse Stress Defined. — 190. Effect of Transverse Stress. Neutral Axis. Relation between the Depth of a Timber and its Resistance to Transverse Stress. — 191. Rankine's Principles concerning Joints and Fastenings 125-128

Joints Connecting Timbers in the Direction of their Length.

192. Lapped Joint. — 193. Fished Joint. — 194. Scarfed Joints. — 195. Scarfed Joint for Resisting Compression. — 196. Scarfed Joint for Resisting Tension. — 197. Scarfed Joint for Resisting Transverse Stresses. — 198. Scarfed Joint for Resisting Ten- ^ sion and Compression. — 199. Scarfed Joint for Resisting Tension and Transverse Stress 1 28-1 31

Xll CONTENTS.

Joints Connecting Timbers at Right Angles.

200. Halving. — 201. Notching. — 202. Cogging. — 203. Mortise-and-Tenon Joints. — 204. Mortise and Tenon Joining a Vertical to a Horizontal Timber. — 205. Mortise and Tenon Joining a Horizontal to a Vertical Timber. — 206. Mortise and Tenon Joining One Horizontal Timber to Another. Tusk Tenon 131-135

Miscellaneous Joints.

207. Oblique Mortise and Tenon. — 208. Bridle Joint. — 209. Tie

Joint. — 210. Chase Mortise , . 135-137

JOINERY.

211. Joinery Described 137

Beads and Moldings.

212. Beads. — 213. Use of Beads. — 214. Chamfer. — 215. Stop Chamfer. — 216. Moldings Described. — 217. Round Nose. — 218. Some Typical Forms of Moldings. Fillet. — 219. Joints

in Joinery Defined 138-140

Heading-Joints, or Joints Uniting Pieces in the Direction of their Length.

220. Square Heading- Joint. Splayed Heading- Joint 141

Joints Uniting Pieces in Direction of their Width.

221. Their Office. — 222. Butt Joint. Filleted Joint. Rabbeted Joint. Matched Joint. — 223. Glued Butt Joint. — 224. Cleating. — 225. Side Cleats. — 226. End Cleats. — 227. Relieving Cleats from Strain 141-144

CONTENTS. Xlll

Joints Uniting Pieces at Right Angles.

228. Butt Joint. — 229. Miter Joint. — 230. Strengthening of Miter Joints. — 231. Dovetail Joints. — 232. Proportions of Mortise-and-Tenon Joints. — 233. Single and Double Tenons. — 234. Haunching. — 235. Four Tenons. — 236. Mortises and Tenons at an Angle in the Work. — 237. Modifications of Mortise-and- Tenon Joints 144-148

Paneling.

238. Panel. — 239. Frame. — 240. Joints between Panel and

FASTENINGS.

PART IV.— TIMBER AND ITS PREPARATION FOR USE. Timber

252. Timber. — 253. Structure of Wood. — 254. Markings of

Wood. — 255. Adaptability of Various Woods . . . 158-166

Characteristics of Typical Timber-Yielding Trees.

256. Classification of Trees. — 257. Exogens. — 258. Effect of Environment. — 259. Broad-Leaved Woods. — 260. Oak. — 261. White Oak. — 262. Red Oak.— 263. Maple. — 264. Sugar Maple. — 265. Silver or White Maple. — 266. Black Walnut. — 267. Yellow Poplar. — 268. Beech. — 269. Ash. — 270. White Ash. — 271. Needle-Leaved Woods. — 272. Pine. — 273. White

XIV CONTENTS.

Pine. — 274. Long-Leaved Pine. — 275. Short-Leaved Pine.

— 276. Loblolly Pine. — 277. Bull Pine. — 278. The Spruces.

— 279. Black Spruce. — 280. White Spruce. — 281. Hemlock.

— 282. Eastern Hemlock. — 283. Western Hemlock. — 284. Bald Cypress. — 285. The Common Redwood. — 286. The Big-Tree Variety of Redwood 166-182

Logging.

287. Felling Timber. — 288. Transportation of Logs. — 289. Sawmills. — 290. Process of Sawing. — 291. Milling. — 292. Water in Timber. — 293. Process of Seasoning. — 294. Air Seasoning. — 295. Steam Drying. — 296. Water Seasoning.

— 297. Kiln Drying. — 298. Kilns. — 299. Shrinkage. — 300. Swelling. — 301. Warping. — 302. Decay in Wood. — 303. Timber Preservation. — 304. Creosoting 182-198

- Strength of Timber.

305. Strength of Timber. — 306. Strength in Tension. — 307. Strength in Compression. — 308. Strength in Shear. — 309. Strength under Transverse Loads 198-200

Introduction

D^C

INTERPRETATION OF MECHANICAL DRAWINGS.

I. Most of the illustrations presented with the following chapters are in the form of Mechanical Drawings. To the novice, these may appear confusing ; but careful attention to

Fig. 1 some of the principles underlying their construction will enable him readily to interpret their meaning.

A mechanical drawing, as distinguished from a perspective drawing, or picture, instead of giving all the characteristics of an object at a glance, presents them in detail, giving in one view one set of elements, in another view another set of elements, and so on, until the form of the object is accurately defined.

For example, Fig. i is a perspective view of an object which is represented mechanically by Fig. 2. By Fig. i it will at once be seen that the object represented is a cylinder. In Fig. 2 there is first presented a plan, showing that the object is cylindrical; and, secondly, an elevation, showing the height of the cylinder. From the combination of these two views, the solid may be as easily imagined as from Fig. i, and the knowledge obtained of it is much more definite.

A perspective view of an object is that which is had by looking from some one point, as A, Fig. 3, while a view represented by a mechanical drawing supposes the ob-

ELEVATION.

BENCH WORK IN WOOD.

server to be looking from an infinite number of points, and always in parallel lines, as indicated by A, Fig. 4.

2. A Plan of any object Fig. 3

represents it as it would appear if, standing on its natural base, it were looked down upon vertically, as indicated by the arrows A, Fig. 5. If the object, as a rectangular block, has no fixed base, any one of its faces may be taken as such.

Fig. 5

3. An Elevation of any object represents it as it would appear if, standing on its natural base, it were looked upon in a horizontal direction, as indicated by arrows B, Fig. 5.

The elevation is always at right angles to the pta?i. There may be several elevations of the same object, each differing from the others as the point of observation changes. For example, the plan and elevation of the object represented by Fig. 6, are usually made as shown by Fig. 7, but they may be made as shown by Fig. 8 or Fig. 9.

Fig.

B

A

III,,

" J

FACE B.

INTRODUCTION.

Fiy;. 9

These angular views, indeed, cannot be avoided when the form they represent is so complicated that its faces are neither parallel, nor at right angles to each other. Fig. 10 is a perspective view of an object which is represented mechanically by Fig. n.

It is evident that if one face of A is shown in the elevation, two faces of B will appear ; if one face of B is shown, two of A will appear.

In the representation of simple objects, the plan is in some cases omitted, and two elevations employed. These may be designated as side elevation and end j \ PLAN.

FACE B.^

.X^FACE A. 1 1

FACE A.

J

VAT(ON.

FACE B.

elevation of a side and an end. For „.

f\ elevation, which terms signify an

elevation of an

example, if we consider the

surface A the base of Fig. 6,

a side elevation would be jg, equivalent to the elevation

Fig. 7, and the end elevation

would become equivalent to the plan of the same figure.

4. Method of showing Parts obscured from Sight. — The outline of details, which in any view of an object are hidden, is frequently shown by dotted lines. Thus, in Fig. 12, the general outline of the plan and elevation shows a rectangular block ; if the circle in the plan is associated with the dotted lines in the elevation, it is not difficult to imagine a round hole extending through the center of the block. If the hole penetrates to only half the depth of the block, dotted lines will be placed as shown by Fig. 13; if the hole is larger at the top

BENCH WORK IN WOOD.

than at the bottom, the drawing will appear as shown by Fig. 14 ; if smaller at the top, as shown by Fig. 15. In Fig. 16 dotted

Fig. 12

Fig. 13

Fig. 14

Fig. IS

O

PLAN.

O

PLAN.

PLAN.

A—

PLAN

EL

1 IVATlffliN,

ELEVATION.

eleVat/on.

l 1

ELEVATION.

lines indicate the diameter of a bolt holding the two pieces A and B together.

5. Sections. — In complicated drawings, the use of dotted lines to indicate hidden parts is more confusing than helpful. In such cases it is customary to imagine the object cut, as if it were sawed asunder, and . the surface thus produced exposed. Such a surface is called a " section."

Complete sections show not only the surface produced by the cut, but the outline of other portions of

Fig. 16

Fig. 17 the object which may be seen beyond. See lines a, a, Fig.

Thus, section AB, Fig. 1 7, is that which would appear if the ring were to be cut on the line AB (Plan, Fig. 17), and the cut surface made to appear in elevation.

Section lines on a drawing show the location of sections. They are usually made in color (red or blue), or in dotted black, with a colored line on each side. Each section is designated by the letters of its section line.

QZZD

Sec. A B.

INTRODUCTION.

Cross-hatching is a term applied to the uniformly spaced parallel lines which are employed to indicate the cut surface of a section. See Fig. 18.

Different pieces of material appearing in the same section are cross-hatched at different angles, as in Fig. 19, which represents a cross-section of a lead-pencil ; and different kinds of material are frequently indicated by cross-hatching in different colors.

Incomplete sections show only the cut surface, to the

exclusion of all other portions of the object. It is

common to place such sections on the section, lines,

and omit the letters. See Fig. 20.

A single view of a symmetrical object may be made partly

in section, and partly in elevation, as in the drawing of the

goblet, Fig. 2i.

"Fig.

IS

W

SECTION A B,

Fig. IO

6. Broken Drawings. — To economize space in representations of simple objects, a portion of the drawing is sometimes omitted.

In such cases, that which is given indicates the character of the omitted portion, and the dimension figures show its extent. An example is given in Fig. 22.

Kig. 21

ELEVATION.i SECTION

7. Scale. — Drawings are made either " full-sized " or "to scale." A full-sized drawing is one in which every dimension agrees exactly with the similar dimension of the object it represents. A drawing to scale is one in which every dimension bears the same fractional relation to the similar dimension of the object it represents. When a drawing is -£-$\ the size of

BENCH WORK IN WOOD.

the object, it is said to be on a scale of ^ inch to the foot, or, as frequently written, i in, = i ft. ; if -J-th the size, as 2 in. = i ft., and so on. The scale 6 in. = 1 ft. is often expressed as "half size.

8. Dimensions. — The various dimensions of an object represented are shown on the drawing by appropriate figures, which express feet when followed by ', and inches when followed by ". Thus 2' should be read as two feet, and 2" as two inches.

12' 7 1"

the same as twelve feet and seven and threequarters inches.

The figures always show the dimensions of the thing represented ; they do not agree with the dimensions of the drawing except when the latter is full-sized. See dimension figures in Fig. 23.

Dimension lines. — Dimension figures are always placed on, or near, lines along which they apply. In drawings these lines are usually in color (red), but may be dotted black, as in Fig. 23. When convenient, they are placed within the outline of the drawing ; but if the drawing is small or crowded, they are placed at one side, and are connected with the parts they limit by perpendicular, colored or dotted lines. Two arrow-heads, one on each side of the dimension figure, locate the points between which it applies. Several dimensions may be given on the same line, each being limited by its own arrow-heads.