Woodwork for secondary schools; a text-book for high schools and colleges, prevocational and elementary industrial schools

Preface

The aim of this book is to provide in text form the essentials of woodwork as usually taught in secondary schools. Manifestly, in a book of this size no one subject can be treated exhaustively. Nor is such treatment necessary to fulfill the purpose of the book, which is to provide the elements of subject-matter for general experience in various lines of woodwork rather than extended experience in some one line. It is confidently expected that the content will be found sufficiently complete for the purpose intended.

Much of the subject-matter, should limitations of time or equipment prevent its use in connection with specific shop experience, may be assigned for reading and study from the purely "informational" point of view. Such assignments, if made so that they shall have some connection with the shopwork, will serve to broaden the pupil's ''outlook," giving to the specific shop experiences a ''setting" calculated to greatly increase the understanding of their meaning.

This text presupposes a knowledge of elementary tool processes, such as are to be found in well organized grade school work, as described in "Essentials of Woodworking," by the same author. However, owing to the lack of any general agreement as to the dividing line between grade school and high school, there will be found included in this text those parts of "Essentials of Woodworking" which observation has shown are frequently not covered in grade schools of good standing. Such duplication makes possible the meeting of diverse conditions now to be found in the division of subject-matter between grade school and high school.

The use of woodworking machines, with the exception of the lathe, by large classes of freshmen is not recommended. The chapter on Woodworking Machines is included in the text for the use of such classes as can be organized with sufficiently small numbers to allow the instructor to give close and continuous attention to the machines. There is no reason, however, why much of such matter may not be read and studied by freshmen as they secure shop experience with the hand tools. A freshman who does not expect to take advanced shopwork in wood will be profited by knowing how much of his hand tool work is duplicated by machines in a way which makes possible cheaper and, if well done, equally good production.

It has been found impracticable to treat the subject of carpentry as a chapter of this text. Then, too, because of physical limitations, carpentry can hardly find a place so nearly universal in the general school curriculum as the more strictly bench subjects. For these reasons carpentry has been treated by the author in a separate text.

Credit is due to John R. Frazier, of Bradley Polytechnic Institute, for the great majority of pen drawings, which assist so greatly in making clear the text ; to C. E. Abbott, of the University of Missouri, for writing the first draft of the chapter on Pattern-making; to Harry L. King, of the Yeatman High School, St. Louis, for the first draft of the cha])ter on Inlaying and Wood-Carving; to Prof. Chas. A. Bennett, of Bradley Polytechnic Institute, Peoria, for valuable additional contributions of both illustrations and text, sections 201. 202, to the same chapter; to Harry L. Hurff, of Bradley Polytechnic Institute, for the first draft

PREFACE. 5

of the chapter on Woodworking Machinery ; to Marshall H. Brigham and N. C. Murray, of the University of Missouri, for generous assistance in arranging materials for photographic illustrations, which, in the main, were the work of James Barham, Agricultural Experiment Station photographer.

IRA S. GRIFFITH.

Columbia, Missouri July, 1915

Chapter I. — Common Woods 1 1

1, Classification. Coniferous woods; 2, Cedar; 3, Cypress; 4, Pine ; 5, Spruce. Broad-leaved woods; 6, Ash ; 7, Basswood; 8, Birch; 9, Butternut; 10, Cherry; U, Chestnut; 12, Elm; 13, Gum; 14, Hickory; 15, Maple; 16, Oak; 17, Sycamore ; 18, Tulip wood ; 19, Walnut.

Chapter II. — Tools and Processes . . . ." 24

20, Flexible folding rule; 21 Pattern-makers' shrinkage rule; 22, Framing square; 23, Octagon scale; 24, Brace measure table; 25, Essex board measure table; 26, Hundredths scale; 27, Rafter table; 28, Determining rafter length by scaling; 29, Plumb and level; 30, Mortise gages; 31, Butt gage; 32, Pattern-maker's gage; Gage attachment; 33, Twist drill gage; 34, Miter square; Combination square; 35, Spring dividers; 36, Calipers; 37, Trammel points or beam compass; 38, Lumberman's board stick; 39, Pattern-maker's knife; 40, Butt chisel; 41, Mortise chisel; 42, Corner chisel; 43, Wood-turning tools; 44, Turner's gouge; 45, Skew or turner's chisel; 46, Scraping tools; 47, Carving tools; 48, Carver's punch; 49, Circular plane; 50, Rabbet or rebate plane; 51, Rabbet or filletstcr plane ; 52, Dado plane ; 53, Plow and matching plane ; 54, Universal plane; 55, Router plane; 56, Scraper plane; 57, Handled scraper ; 58, Veneer scraper ; 59, Core-box plane ; 60, Drawing knife; 61, Expansion or extension bit; 62, Nut augers ; 63, Angular boring attachment ; 64, Extension bit holder; 65, Breast drill; 66, Hand drill; 67, Automatic hand drill; 68, Spiral screwdriver; 69, Awls; 70, Wrecking bar; 71, Nail puller; 72, Glass cutter; 73, Files and rasps; 74, File cleaner; 75, BeU punch; 76, Plug cutter; 77, Screw and plug bit; 78, Washer cutter; 79, Emery wheel dresser; 80, Sharpening auger bits; 81, Forstner auger bit; 82, Sharpening saws; 83, Sharpening scrapers; 84, Sharpening lathe tools; 85, Sharpening carving tools; 86, Modeling; 87, Glue pots; 88, Surface

table.

8 WOODWORK FOR SECOXDARV SCHOOLS.

Chapter III.— Woodworking ^Machines 7(^

89, Introductory; 90, Order of procedure in the use of machines; 91, Swing cut-off saw; 92, Operating a swing cut-off saw; 93, Hand planer or jointer; 94, Setting up a hand planer or jointer; adjustments; 95, Cutter heads; set-up and titment of knives ; 96, Operation of a hand planer or jointer; 97, Jointer guard; 98, Planer or surfacer ; 99, Operation of a surfacer ; 100, Adjustments on a surfacer; 101, Circular saws; 102, Operation of a universal saw; 103, Cutting tenons with a universal saw; 104, Cutting wedges on a universal saw ; 105, Kerfing a cove for molding or core-box ; 106, Table for set-up of universal saw for compound miters ; 107, Grooving and dado or gaining heads for universal saw ; 108, Circular miter saws; 109, Fitting and filing circular saws; 110, The band saw; 111, Operation of a band saw; 112, Resawing attachment for band saw; 113, Filing and fitting a band saw; 114, Brazing small band saws; 115. The scroll saw; 116, Boring machine; 117, Operation of a boring machine; 118, Mortiser ; 119, Operation of a hollow chisel mortiser; 120, Tenoner; 121, The shaper ; 122, The lathe; 123, Sanders; 124, The belt sander; 125, Disc and spindle sander ; 126, The trimmer ; 127, Miter plane and chute board; 128, Miter-box; 129, Picture frame miter-box and nailing clamp; 130, Automatic grinder; 131. The grindstone; 132, Power transmission; 133, Splicing belts; 134. Selection of belting; 135, Babbitting bearings; 136, Dust exhaust system ; 137, Shaft drive vs. individual motor drive ; 138, Calculating speeds and diameters of pulleys, saws, grindstones, etc.

Chapter IV. — Joinery 1 52

139, Joinery; 140, General directions for joinery; 141. Dado; 142, Directions for dado; 143, Cross-lap joint; 144, Directions for cross-lap joint; 145. Directions for cross-lap joint — second tiictlud; 146. Glue joint; 147, Directions for glue joint; 148, Doweling; 149, Directions for doweling; 150, Keyed tenon-and-mortise ; 151, Directions for key; 152, Directions for tenon; 153, Directions for mortise; 154, Directions for mortise in the tenon; 155, Blind mor-

CONTENTS. 9

tise-and-tenon ; 156, Directions for tenon; 157, Directions for laying out mortise; 158, Directions for cutting mortise; 159, Directions for cutting mortise — second method: 160, Miter joint; 161, Directions for miter joint; 162, Dovetail joint; 163, Directions for dovetail joint; 164, Additional joints; 165, Hopper joint; 166, Doweled joint; 167, Pinned mortise-and-tenon ; 168, Coped joint.

Chapter V. — Wood Turning 185

169, Turning between centers; 170, Centefing the stock; 171, Adjusting the tool rest; 172, Position of the operator; 173, Use of the large gouge; 174, Use of the outside calipers; 175, Use of the large skew; 176, Cutting off; Use of parting tool; 177, Use of the toe of the skew to dress off an end; 178, Heel of the skew used to cut a shoulder; 179, Long taper cuts; 180, Laying off consecutive measurements; 181, Making full v-grooves ; 182, Short convex cuts; beads; 183, Concave cuts; 184, Long convex cuts; 185, Face-plate and chuck work; 186, Face-plates; Preparation of the stock; 187, Rough scraping; 188, Convex and concave scraping; 189, Chucks; their use; 190. Sandpapering and finishing.

Chapter VL — Inlaying and Wood-Carving 215

191, Inlaying; general considerations; 192, Directions for forming and fitting inlays of irregular outline ; 193, strings and bandings; 194, Directions for building up a typical banding; 195, Directions for laying strings and bandings; 196, Directions for marquetry; 197, Finishing; 198, Wood-carvina^ ; 199, General directions; 200, Line carving; 201, Ribbon carving; 202, Grounding out and molding; 203, Modeling; 204, Light and shade; 205, Finishing carvings ; 206, Pierced ornamentation.

Chapter VII. — Wood Finishing 239

207, Wood finishes; 208, Brushes; 209, General directions for using brush; 210, Fillers; 211, Filling with paste filler; 212, Stains; 213, Waxing; 214, Varnishes; 215, Shellac; 216, Shellac finishes; 217, Oil or copal varnishes; 218, Flowing copal varnish; 219, Typical finishes for coarse-grained woods; 220, Patching; 221, Painting; 222, Wood finishing recipes.

Chapter VIII. — Furniture Construction 254

223, General discussion ; 224, Designing ; 225, Structural details ; 226, Posts or legs ; 227, Corner fastenings ; 228, Slats, splats or splads ; balusters ; 229, Chairs ; 230, Patching; 231, Curved work; 232, Veneering; 233, Clamping table tops; 234, surfacing table tops; 235, Clamping framed structures; 236, Adjusting the clamps; clamping a section; 237, Assembling the sections; 238, Scribing the posts; 239, Clamping miters; 240, Fastening tops; 241, Drawer runners and guides ; 242, Drawer construction ; 243, Directions for rabbeted corner ; 244, Directions for dovetail corner ; 245, Directions for drawer ; 246, Paneling ; 247, Cutting grooves; 248, Haunched mortise-and-tenon ; 249, Rabbeting; 250, Fitting a door; 251, Hinging a door; 252, Locks ; 253, Carcase construction ; 254, Shelving ; 255, Rods ; 256, Templets ; 257, Period furniture ; 258, Moldings; 259, Simple upholstering; 260, Spring or box seat; 261, Woven reed seat; 262, Rush fiber seat: 263, Cane seating.

Chapter IX. — Pattern Making . . 320

264, • Pattern-making ; 265, Materials ; 266, Flasks ; 267, Molding operations ; 268, Determining factors in the construction of a pattern ; 269. Molding sand ; 270, Pattern draft; 271, Shrinkage; 272, Shrinkage vs. rappage ; 273, Double shrinkage ; 274, Finish ; 275, Making a "lay-out" ; 276, Order of procedure ; 277, Fillets ; 278, Cores ; core-prints ; core-boxes ; 279, Vertical cores and core-prints ; 280, Horizontal cores; 281, Balanced cores; 282, Stop-ofif cores ; 283, Stop-off core-box ; 284, Wood face-plates ; 285, Segments; 286, Lap joint for six-arm pattern; 287, La\'ing out arms ; 288, Forming arms ; 289, Spur gear teeth; 290, Bevel gears; 291, Split patterns; dowels; 292, Turning split patterns ; 293, Tee-pipe fittings ; 294, Elbow ; offset ; return bend ; 295, Loose pieces ; 296, Burning iron ; 297, Affixing letters or numerals ; 298, Varnishing patterns.

CHAPTER I. Common Woods

1. Classification. — According to botanical classification, woods belong to the Flowering Plants (Phanerogamia). Classified further we have:

(1) Naked seeds (gymnosperms)

1. Palm ferns, etc. (cycadaceae)

2. Joint firs (gnetaceae)

3. Pines, firs, etc. (conifers)

(2) Fruits (angiosperms)

1. One-seed-leaf (monocotyledons) (bamboos, palms, grasses, etc.)

2. Two-seed-leaf (dicotyledons)

a. Herbs

b. Broad-leaved trees (oak, ash, elm, etc.)

Conifers and broad-leaved trees are alike in that they add a new layer of wood each year which covers the old wood of root, trunk, and branch. They are known as exogens — outward growers.

In woods such as the palms, bamboos, and yuccas, growth is made from within.

The new wood strands mingle with the old and cause the cross sections to appear dotted. Fig. 1. Trees of this class — endogens — after some years of growth form harder wood near the surface with younger and softer growth toward the center — quite the reverse of the

WOODWORK FOR SECONDARY SCHOOLS.

exogens. There are no annual rings. Growth takes place mainly at the top.

Other classifications, such as ''deciduous," "hard woods," ''evergreens,"

"soft woods," are in common use but are not very accurate.

Deciduous trees are the broad-leaved trees and are so called because they lose their leaves in the fall. Broad-leaved trees are also called hard woods. Conifers are called evergreens because their needleshaped leaves remain green on the tree the year around. They are also known as soft woods.

Most of our timber is furnished by (1) the needleleaved conifers and (2) the broad-leaved trees.

Fig. 1.

Section of Endogen

CONIFEROUS WOODS.i

2. Cedar. — Fig. 2. Light, soft, stifif, not strong, of fine texture ; sap and heartwood distinct, the former lighter, the latter a dull grayish brown, or red. The wood seasons ^rapidly, shrinks and checks but little, and is very durable. Used like soft pine, but owing to its great durability preferred for shingles, etc. Small sizes used for posts, ties, etc. (Since almost all kinds of wood are used for fuel and charcoal, and in the construction of fences, barns, etc., the enumeration of these uses has been

Cedar.

^The descriptive matter on woods is quoted, by permission, from a report of the Division of Forestry, U. S. Department of Agriculture, Washington, D. C. — Bulletin No. 10, Timber — to which the student is referred for further information about trees.

COMMON WOODS.

omitted in this list.) Cedars usually occur scattered, but they form, in certain localities, forests of considerable

extent.

3. Cypress.— Fig 3. Cypress wood in appearance, quality, and uses is similar to white cedar. ''Black cypress" and "white cypress" are heavy artd light forms of

Fig. 3. Cypress.

Fig. 4. Pine.

the same species. The cypress is a large deciduous tree occupying much of the swamp and overflow land along the coast and rivers of the Southern States.

4. Pine.— Fig. 4. Very variable, very light and soft in "soft" pine, such as white pine; of medium weight to heavy and quite hard in "hard" pine, of which longleaf or Georgia pine is the extreme form. Usually it is stifif, quite strong, of even texture, and more or less resinous. The sapwood is yellowish white ; the heartwood, orange brown. Pine shrinks moderately, seasons rapidly and without much injury; it works easily; is never too hard to nail (unlike oak or hickory) ; it is mostly quite durable, and if well seasoned is not subject to the attacks of boring insects. The heavier the wood, the darker, stronger and harder it is, and the more it shrinks and checks. Pine is

WOODWORK FOR SECONDARY SCHOOLS.

used more extensively than any other kind of wood. It is the principal wood in common carpentry, as well as in all heavy construction, bridges, trestles, etc. It is used also in almost every other wood industry, for spars, masts, planks, and timbers in ship building, in car and wagon construction, in cooperage, for crates and boxes, in furniture work, for toys and patterns, railway ties, water pipes, excelsior, etc. Pines are usually large trees with few branches, the straight, cylindrical, useful stem forming by far the greatest part of the tree.

5. Spruce. — Fig, 5. Resembles soft pine, is light, very

soft, stiff, moderately strong, less resinous than pine ; has no distinct heartwood, and is of Avhitish color. Used like soft pine, but also employed as resonance wood and preferred for paper pulp.

Spruces, like pines, form extensive forests ; they are more frugal, thrive on thinner soils, and bear more shade, but usually require a more humid climate. "Black" and 'Svhite" spruce, as applied by lumbermen, usually refer to narrow and wide ringed forms of black spruce.

Spruce.

BROAD-LEAVED WOODS.

6. Ash. — Fig 6. Wood heavy, hard, strong, stiff, quite tough, not durable in contact with soil, straight grained, rough on the split surface and coarse in texture. The wood shrinks moderately, seasons with little injury,

COMMON WOODS.

IS stands well and takes a good polish. In carpentry ash is used for finishing lumber, stairways, panels, etc. ; it is used in shipbuilding, in the construction of cars, wagons, carriages, etc., in the manufacture of farm implements, machinery, and especially furniture of all kinds, and also for harness work ; for barrels, baskets,* oars, tool

Fig. 6. Ash.

Fig. 7. Basswood.

handles, hoops, clothespins, and toys. The trees of the several species of ash are rapid growers, of small to medium height with stout trunks ; they form no forests, but occur scattered in almost all broad-leaved forests.

7. Basswood. — Fig. 7. (Lime tree, American linden, lin, bee tree) : Wood light, soft, stiff but not strong, of fine texture, and white to light brown color. The wood shrinks considerably in drying, works and stands well ; it is used in carpentry, in the manufacture of furniture and woodenware, both turned and carved, in cooperage, for toys, also for paneling of car and carriage bodies. Medium to large sized trees, common in all northern broad-leaved forests ; found throughout the eastern United States. 2 i6

WOODWORK FOR SECONDARY SCHOOLS.

8. Birch. — Fig-. 8. Wood heavy, hard, strong, of fine texture; sapwood whitish, heartwood in shades of brown with red and yellow ; very handsome, with satiny luster, equaling" cherry. The wood shrinks considerably in drying, works and stands well and takes a good polish, but is not durable if exposed. Birch is used for finishing lumber in building, in the manufacture of furniture, in woodturnery, for spools, boxes, wooden shoes, etc., for shoe lasts and pegs, for wagon hubs, ox yokes, etc., also in wood-carving. The birches are medium sized trees, form extensive forests northward and occur scattered in all broad-leaved forests of the eastern United States.

9. Butternut.— Fig. 9. (White Walnut.) Wood very similar to black walnut, but light, quite soft, not strong and of light brown color. Used chiefly for finishing

Fig. 8. Birch.

Fig. 9. Butternut.

lumber, cabinet-work and cooperage. Medium sized tree, largest and most common in the Ohio basin ; Maine to Minnesota and southward to Georgia and Alabama.

10. Cherry. — Fig. 10. Wood heavy, hard, strong, of fine texture ; sapwood yellowish white, heartwood reddish to brown. The wood shrinks considerably in drying, works and stands well, takes a good polish, and is much

COMMON WOODS.

esteemed for its beauty. Cherry is used chiefly as a decorative finishing lumber for buildings, cars and boats, also for furniture and for turnery. It is becoming too costly for many purposes for which it is naturally suited.

Jv Fig. 10. Cherry.

Fig. 11. Chestnut.

The lumber-furnishing cherry of this country, the wild black cherry, is a small to medium sized tree, scattered thru many of the broad-leaved woods of the western slope of the Alleghanies, but found from Michigan to Florida and west to Texas.

11. Chestnut. — Fig. 11. Wood light, moderately soft, stifif, not strong, of coarse texture ; the sapwood light, the heartwood darker brown. It shrinks and checks considerably in drying, works easily, stands well, and is very durable. Used in cabinet-work, cooperage, for railway ties, telegraph poles, and locally in heavy construction. Medium sized tree very common in the Alleghanies, occurs from Maine to Michigan and southward to Alabama.

12. Elm. — Fig. 12. Wood heavy, hard, strong, very tough ; moderately durable in contact with the soil ; commonly cross-grained, difficult to split and shape, warps and checks considerably in drying, but stands well if

WOODWORK FOR SECONDARY SCHOOLS.

Fig. 12. Elm.

properly handled. The broad sapwood whitish, heart brown, both shades of gray and red; on split surface rough, texture coarse to fine, capable of high polish. Elm

is used in the construction of cars, wagons, etc., in boat and ship building, for agricultural implements and machinery; in rough cooperage, saddlery, and harness work, but particularly in the manufacture of all kinds of furniture, where the beautiful figures, especially of the tangential or bastard section, are just beginning to be duly appreciated. The elms are medium to large sized trees, of fairly rapid growth, with stout trunk, form no forests of pure growth, but are found scattered in all the broad-leaved woods of our country.

13. Gum. — This general term refers to two kinds of wood, usually distinguished as sweet or red gum, and sour, black, or tupelo gum, the former being a relative of the witch-hazel, the latter belonging to the dogwood family.

Sweet Gum. Fig, 13. (Red gum, liquidambar) ; wood rather heavy, rather soft, quite stiff and strong, tough, commonly cross-grained, of fine texture; the broad sapwood whitish, the heartwood reddish brown ; the wood warps and shrinks considerably, but does not check badly, stands well when fully seasoned, and takes good polish. Sweet gum is used in carpentry, in the manufacture of furniture, for cut veneer, for wooden plates,

COMMON WOODS.

plaques, baskets, etc., also for wagon hubs, hat blocks, etc. A large sized tree, very abundant, often the principal tree in the swampy parts of the bottoms of the Lower Mississippi Valley ; occurs from New York to Texas and from Indiana to Florida.

14. Hickory. — Fig. 14. Wood very heavy, hard and strong, proverbially tough, of rather coarse texture, smooth and of straight grain. The broad sapwood white,

Fig. 13. Gum.

Fig. 14. Hickory.

the heart reddish nut brown. It dries slowly, shrinks and checks considerably, is not durable in the ground or if exposed, and, especially the sapwood, is always subject to the inroads of boring insects. Hickory excels as carriage and wagon stock, but is also extensively used in the manufacture of implements and machinery, for tool handles, timber pins, for harness work and cooperage. The hickories are tall trees with slender stems, never form forests, occasionally small groves, but usually occur scattered among other, broad-leaved trees in suitable localities.

WOODWORK FOR SECONDARY SCHOOLS.

15. Maple. — Fig. 15. Wood heavy, hard, strong, stiff, and tough, of fine texture, frequently wavy grained, thus giving rise to "curly" and "blister" figures ; "not durable

in the ground or otherwise exposed.

Maple is creamy white, with shades of light brown in the heart ; shrinks moderately, seasons, works and stands well, wears smoothly and takes fine polish. The wood is used for ceiling, flooring, paneling, stairway and other Fig. 15. Maple. finishing lumber in

house, ship and car construction ; it is used for the keels of boats and ships, in the manufacture of implements and machinery, but especially for furniture, where entire chamber sets of maple rival those of oak. Maple is also used for shoe lasts and other form blocks, for shoe pegs, for piano actions, school apparatus, for wood type in show bill printing, tool handles, wood-carving, turnery and scroll work.

The maples are medium sized trees, of fairly rapid growth ; sometimes form forests and frequently constitute a large proportion of the arborescent growth.

16. Oak. — Fig. i6. Wood very variable, usually very heavy and hard, very strong and tough, ])()rous, and of coarse texture ; the sapwood whitish, the heart "oak" brown to reddish brown. It shrinks and checks badly.

COMMON WOODS.

giving trouble in seasoning, but stands well, is durable and little subject to attacks of insects. Oak is used for many purposes : in shipbuilding, for heavy construction, in common carpentry, in furniture, car and wagon work, cooperage, turnery, and even in wood-carving ; also in the manufacture of all kinds of farm implements, wooden mill machinery, for piles and wharves, railway ties, etc. The oaks are medium to large sized trees, forming the predominant part of a large portion of our broad-leaved forests, so that these are generally ''oak forests" though they always contain a considerable proportion of other kinds of trees. Three well marked kinds, white, red, and live oak are distinguished and kept separate in the market. Of the two principal kinds, white oak is the stronger, tougher, less porous, and more durable. Red oak is usually of coarser texture, more porous, often brittle, less durable, and even more troublesome in seasoning than white oak. In carpentry and furniture work, red oak brings about the same price at present as white oak. The red oaks everywhere accompany the white oaks, and like the latter, are usually represented by several species in any given locality. Live oak, once largely employed in shipbuilding, possesses all the good quailties (except that of size) Of the white oak, even to a greater degree. It is one of the heaviest, hardest and most durable building timbers of this country; in structure it resembles the red oak but is much less porous.

WOODWORK FOR SECONDARY SCHOOLS.

17. Sycamore. — Fig. 17. (Button wood, button-ball tree, water beech) : Wood moderately heavy, quite hard, stiff, strong, tough, usually cross-grained, of coarse texture, and white to light brown color ; the wood is hard to split and work, shrinks moderately, warps and checks considerably but stands well. It is used extensively for

Fig. 17. Sycamore.

Fig. 18. Tulip Wood.

drawers, backs, bottoms, etc., in cabinet-work, for tobacco boxes, in cooperage, and also for finishing lumber, where it has too long been underrated. A large tree, of rapid growth, common and largest in the Ohio and Mississippi valleys, at home in nearly all parts of the eastern United States.

18. Tulip Wood.— Fig. 18. Tulip tree. (Yellow poplar, white wood) : Wood quite variable in weight, usually light, soft, stiff but not strong, of fine texture, and yellowish color; the wood shrinks considerably, but seasons without much injury; works and stands remarkably well. Used for siding, for paneling, and finishing lumber in house, car and shipbuilding, for sideboards and panels of wagons and carriages ; also in the manufacture of furniture, implements and machinery, for pump logs, and almost every kind of common woodenware, boxes,

COMMON WOODS.

shelving, drawers, etc. An ideal wood for the carver and toy man. A large tree, does not form forests, but is quite common, especially in the Ohio basin ; occurs from New England to Missouri and southward to Florida.

19. Walnut. — Fig. 19. Black walnut. Wood heavy, hard, strong, of coarse texture ; the narrow sapwood whitish, the heartwood chocolate brown. The wood shrinks moderately in drying, works and stands well, takes a good polish, is quite handsome, and has been for a long time the favorite cabinet wood in this country. Walnut formerly used even for fencing, has become too

Fig. 19. Walnut.

costly for ordinary uses, and is today employed largely as a veneer, for inside finish and cabinet-work, also for turnery, for gunstocks, etc. Black walnut is a large tree, with stout trunk, of rapid growth, and was formerly quite abundant throughout the Alleghany region, occurring from New England to Texas, and from Michigan to Florida.

Fig. 20. Flexible Folding Rule.

CHAPTER 11.

Tools and Processes.^

20. Flexible Folding Rule. — The flexible folding rule is used by carpenters and others where distances to be

measured usually ex- II ^-^=r^==.._ ceed two feet. It is

made of flexible hard wood with steel riveted joints. Each joint contains a stiff spring which holds the parts in position when open. It can be obtained in four, six and eight foot lengths. Fig. 20.

Ihe rule shown in Fig. 21 differs from the ordinary flexible rule in that it has a sliding extension which makes possible inside calipering. This will be found very convenient in all work requiring inside measurements. Such rules will measure four or six feet plus the length of the extension.

21. Pattern-Maker's Shrinkage Rule.— All metals, w h e n c a s t,

shrink in cool-

i n g. The

amount of

shrinkage d e-

pends upon the

kind of metal,

the thickness of

the piece cast, and the conditions under wliich it. is cast.

1 Xo attempt is made to list in this chapter such tools as are ordinarily made use of in grammar grade woodworking.

Fig. 21.

Folding Rule and Extension.

Under ordinary conditions, where the thickness of the casting is about 1", the average shrinkage is as follows for the following metals : Cast iron, ^" ; steel, |" ; brass, j\" ; tin, 1/12". If the castings are thicker the shrinkage will average less ; if thinner, more under the same conditions of casting.

In order to allow for this shrinkage patterns must be made correspondingly larger than the finished casting is to be. Shrinkage rules are graduated to make such allowances for the various metals used in common foundry practice. The figures on a shrink rule refer to the dimensions of the casting, but the spacings are such as will give the proper size for the pattern. Fig. 22. Thus, a rule for use in making patterns to be cast in iron will have a shrinkage allowance of I" per foot, making the rule 24^" long with graduations into 8ths, 16ths, 32nds and 64tlis. A shrinkage rule for steel will have a length of 24^', and brass 24f".

Fig. 22. Pattkrn-Maker's Shrinkage Rule.

22. Framing Square. — The framing square consists of two parts, the blade which is 24'' long and the tongue which is either 16" or 18" long. The blade is 2" wide and the tongue is H". Such squares are variously marked. In addition to the linear graduations, there will usually be found tables of various sorts, different makes having different tables and arrangements. That side of a square having the maker's name stamped thereon, is considered the face.

23. Octagon Scale. — Along the middle of the face of the tongue of certain squares will be found a scale like

WOODWORK FOR SECONDARY SCHOOLS.

that shown in Fig. 23. This is known as an octagon or eight-square scale, and is used as its name impHes for laying out octagons.