i 
 
m: 
 
ESSENTIALS IN 
 MECHANICAL DRAWING 
 
THE MACMILLAN COMPANY 
 
 NEW YORK • BOSTON • CHICAGO • DALLAS 
 ATLANTA • SAN FRANCISCO 
 
 MACMILLAN & CO., Limited 
 
 LONDON • BOMBAY • CALCUTTA 
 MELBOURNE 
 
 THE MACMILLAN CO. OF CANADA, Ltd. 
 
 TORONTO 
 
ESSENTIALS 
 
 IN 
 
 MECHANICAL DRAWING 
 
 BY 
 
 L. J. SMITH, B.S. 
 
 PROFESSOR OF AGRICULTURAL ENGINEERING, MANITOBA AGRICULTURAL 
 
 COLLEGE ; FORMERLY INSTRUCTOR IN CHARGE OF THE DIVISION 
 
 OF FARM MECHANICS, MICHIGAN AGRICULTURAL 
 
 COLLEGE ; MEMBER OF THE AMERICAN 
 
 SOCIETY OF AGRICULTURAL 
 
 ENGINEERS 
 
 THE MACMILLAN COMPANY 
 1917 
 
 All rights reserved 
 

 Copyright, 1917, 
 By the MACMILLAN COMPANY. 
 
 Set up and electrotyped. Published May, 1917. 
 
 -0 
 
 
 
 MAY 10 1917 
 
 .1. S. Gushing Co. — Berwick & Smith Co. 
 Norwood, Mass., XT.B.A. 
 
 ^CI,A4G0653 
 
PREFACE 
 
 This brief treatment of the essentials of mechanical 
 drawing is designed to give instruction in the rudiments of 
 plan drawing as it occurs in everyday life, so that the student 
 will be able to read and understand ordinary drawings 
 and be able to do ordinary mechanical sketching. The 
 book should be of value also to one who is about to take 
 a longer course in drawing, for it aims to correct the com- 
 mon mistakes of the beginner. 
 
 Where work is given without the regular instruments, 
 it is well to provide the students with small drawing boards 
 about 12 X i8 inches in size, together with a T square. 
 This equipment makes for more rapid and accurate work. 
 The bottom edge of the drawing board can be planed 
 square with the left side so that the T square may be used 
 for both horizontal and vertical lines. 
 
 The lists of exercises offered are merely suggestive. 
 Where possible it is best to have drawings made from the 
 object itself rather than from another drawing. This is 
 possible even in the drafting room, in institutions where 
 shop work is given, for one can there secure enough joints or 
 other woodwork so that at least every two students will 
 have the object on the drafting table. 
 
VI PREFACE 
 
 Some of the drawings offer good exercises in making 
 detail sketches of each piece in the object. Good practice 
 can be had also in getting out the bill of material of the 
 lumber required for some of the objects shown. The 
 workbench or the pig cot furnishes the beginner a good 
 exercise along this line. 
 
 While the book is designed primarily for use in the 
 drafting room, the exercises shown are such as to be of 
 value for use as a course in practical wood shop in schools 
 of agriculture. 
 
 The writer believes that the time will soon come when 
 our schools and colleges will consider elementary mechan- 
 ical drawing at least equal in educational value to free- 
 hand drawing. 
 
 L. J. SMITH. 
 
 March, 19 17. 
 
ESSENTIALS IN 
 MECHANICAL DRAWING 
 
ESSENTIALS IN MECHANICAL 
 DRAWING 
 
 MECHANICAL SKETCHING 
 
 Introduction. — Mechanical drawing is, in these days of 
 careful planning, the basis of all constructive work. The 
 building of ships, the erection of the home, the large fac- 
 tory, or the sky-scraping office building, the construction 
 of large locomotives, or of any of the great public works, is 
 always preceded by very careful and complete drawings 
 previously planning all arrangements in detail. 
 
 A knowledge of mechanical drawing is not only essential 
 in the constructive trades and professions, but it is of 
 value in almost all walks of life. The newspapers and 
 magazines make wide use of drawings. Educational 
 books dealing with the more practical phases of life are 
 illustrated in this way. Indeed, the general public will 
 never get the benefit of many of the new ideas, nor be able 
 to give others the benefit of their own experience, with- 
 out sotne knowledge and use of mechanical drawing. 
 
 It is not necessary to take a long course of instruction 
 in order to be able to make or understand ordinary draw- 
 
2 ESSENTIALS IN MECHANICAL DRAWING 
 
 ings. The making of six or eight pencil sketches will be 
 sufficient to give the ordinary student a general knowledge 
 of the subject. He will, of course, not become an expert, but 
 he will have laid a good foundation for future development. 
 
 Neither is it necessary to have an expensive set of in- 
 struments in order to make sketches and learn to inter- 
 pret drawings. With a good foot rule graduated into 
 sixteenths of an inch, a compass fitted with hard lead, a 
 fairly hard drawing pencil (3 or 4 H), and an eraser, it is 
 possible with very little expense to make quite complicated 
 drawings in lead, and to learn a great deal about lettering 
 and drawing in general. 
 
 What mechanical drawing is. — In ordinary free-hand 
 drawing where the work is done in " perspective," making 
 picture drawings of the objects, the drawings usually 
 show three sides of the object, or enough to completely 
 represent it, in the one view. In mechanical drawing, 
 the thing represented is shown by means of two or more 
 views, each view showing one side of the object. In this 
 kind of drawing, therefore, several views of the object 
 are necessary and must be studied in relation to each 
 other, in order to give a proper conception of that object. 
 As an illustration, consider the object shown in Fig. i, in 
 one view only. In this drawing the eye sees three sides 
 of the block at the same time and readily understands 
 what is represented. A complicated drawing to accurate 
 scale cannot readily be made showing three sides of the 
 object, and so the idea of separate views has come into use. 
 
MECHANICAL SKETCHING 3 
 
 Names of views. — Figure 2 shows a mechanical drawing 
 of the same block, which is 2" ^ long, f wide, and f high 
 on one side, and f high on the other. T represents the 
 top view or plan of the block, 5 the side view or side 
 elevation, and E the end view or end elevation. It will 
 be noticed that the views are in line with each other. 
 
 Figure i. 
 
 that is, the top view is directly above the side view, and 
 the end view is directly to the right of the side view, 
 as shown by the light dotted lines which in practice 
 are not drawn. The lines a and h will be parts of the 
 same vertical line, and c and d of the same horizontal 
 line. 
 
 ^ The two short dashes above at the right of a number denote inches, 
 while one dash means feet. 
 
4 
 
 ESSENTIALS IN MECHANICAL DRAWING 
 
 The terms ^' plan " and ^' elevation " are used in con- 
 nection with architectural drawings and many civil en- 
 gineering drawings, while the word " view " is commonly 
 applied to other mechanical drawings. In plans for 
 buildings, the drawings of the various lay-outs of each 
 floor are called floor plans — first-floor plan, second-floor 
 
 -Q 
 ^ 
 
 
 
 
 
 n 
 
 T 
 
 
 
 
 
 
 
 ^^ 
 
 
 5 
 
 
 E 
 
 
 c 
 
 
 cf 
 
 
 Figure 2. 
 
 plan, basement plan, etc. Sometimes the side, top, and 
 end views are not sufficient, in which case a drawing is 
 made showing part of the object cut away, and this 
 drawing is called a ^' sectional view." In reality the floor 
 plans of a building are sectional views, showing what 
 would be seen if the upper part of the building were cut 
 away down to the center of the windows of the particular 
 floor plan sho\vn. 
 
MECHANICAL SKETCHING 5 
 
 Position of the eye in relation to the views. — In mechan- 
 ical drawing, if a top view is wanted, it is supposed to be 
 drawn as seen by the eye placed directly above the object ; 
 if a side view is being made, the eye must view the object 
 from that side ; or if the end view is necessary, it is rep- 
 resented as if the eye were looking directly at the end of 
 the object. The eye is supposed to be far enough away so 
 that the rays of light coming from each point on the side 
 of the object shown enter the eye in parallel lines. This 
 must be continually kept in mind by beginners. 
 
 Isometric drawings. — The isometric drawing affords one 
 of the most common methods of showing an object mechani- 
 cally in one view only. In this type of drawing the object 
 is drawn as viewed from such an angle that all edges of 
 rectangular objects are cut down from their true length the 
 same proportionate amount. Because of this fact the lines 
 are commonly drawn the same length as the lines of the object 
 represented. Figure 3 represents an isometric drawing of 
 a half dovetail joint. The rectangular edges are usually 
 drawn vertically, or 30 degrees from the horizontal (see 
 Fig. 4) ; the vertical edges of the object being drawn verti- 
 cal, and the edges running lengthwise and crosswise are 
 drawn at an angle of 30 degrees from the horizontal. All 
 other lines are obtained by reference to the lines represent- 
 ing rectangular edges. 
 
 The parallel lines of an object are shown parallel in 
 isometric drawings instead of sUghtly converging as they 
 do in perspective drawings. On account of this fact, 
 
6 ESSENTIALS IN MECHANICAL DRAWING 
 
 isometric drawings of large objects do not look natural, 
 and the use of these drawings is limited to smaller articles ; 
 but they are very serviceable in conveying ideas to those 
 who are not able to understand mechanical drawings. 
 
 HALF DOVE TAIL JOINT, 
 Scafe Name. 
 
 Figure 3. 
 
 To get the angle of 30 degrees where no 30 degree tri- 
 angle is to be had, use the protractor ; or in case none is 
 at hand, draw an equilateral triangle with one side vertical 
 to an imaginary horizontal Hne ; the other two sides will 
 be at an angle of 30 degrees with this line. 
 
 One can buy pads of 9'' X 12'' isometric section paper 
 which is lined horizontally and vertically into squares, 
 
MECHANICAL SKETCHING 
 
 and which has lines also running each way at an angle 
 of 30 degrees with the horizontal. 
 
 The angle iron in Fig. 4 is a very simple example of this 
 
8 ESSENTIALS IN MECHANICAL DRAWING 
 
 type of drawing. It also gives the method of putting in 
 dimensions. 
 
 Where the isometric drawings are made of cylindrical 
 objects, the circle appears as an ellipse which is usually 
 drawn by an approximate method. First draw an isomet- 
 ric square whose sides are the same length as the diameter 
 of the circle. The ellipse will be drawn tangent to the center 
 of the sides of the square at c, e^ d, and /. Draw line ab 
 and Knes cd and ef. Draw ch and gd, and these lines inter- 
 sect ab at i and 7 respectively. With these points i srndj 
 as centers, draw curves ce and df. Then with points g and 
 h as centers, draw the curves ed and /c, completing the 
 ellipse. 
 
 It is not difficult to make an isometric drawing of curved 
 surfaces or edges. Figure 5 illustrates a common method 
 of procedure. The end view and the end of the isometric 
 drawing are divided into the same number of spaces. 
 The lengths of the lines i, 2, 3, etc., are measured on the 
 end view of the mechanical drawing or the end of the 
 object itself. Then the lengths are transferred to the ends 
 of the isometric drawing, thus locating points on the curve. 
 
 Size of drawings. — Objects are represented on paper to 
 different scales or sizes, depending on the size of the paper 
 and of the object to be shown. Small objects are generally 
 represented in the drawing in full or actual size. Very small 
 objects may be magnified and shown on paper double their 
 actual size. If the drawing is half size, the scale will be 
 " 6 inches equals i foot," meaning that 6 inches of the 
 
MECHANICAL SKETCHING Q 
 
 drawing represents a foot of the actual object. The follow- 
 ing are equivalent sizes and scales : — 
 
 Size Scale 
 
 One half &' =i' 
 
 One quarter 3" = i' 
 
 One eighth i|'' -= i' etc. 
 
 If a drawing is made full size, the scale is not put on the 
 drawing, but simply the words " Scale, full size." In 
 
 Figure 5. 
 
 architectural work and in other drawings representing 
 large objects, the scale is very often as small as i'' = 1'. The 
 ordinary rule with the inches divided into sixteenths 
 answers very well for quite a wide variety of scales in 
 mechanical sketching. If one is doing a good deal of this 
 work, however, it is better to buy the regular triangular 
 
10 ESSENTIALS IN MECHANICAL DRAWING 
 
 rule, which has twelve different scales on the one piece of 
 wood. This rule, however, should never be used as a straight 
 edge for drawing lines. 
 
 Dimensions. — No matter to what scale the drawing is 
 made, the full dimensions are put on the drawing. This is 
 very important. For example; if a drawing were made 
 half size, and if the dimensions put on the drawing were also 
 all reduced by half, then the drawing itself would be a full- 
 size drawing of an object only one half as large as the one 
 to be constructed; and, if so used, would result in the 
 object being made half size. 
 
 As far as practicable, the dimensions are put at the 
 bottom, and to the right of the various views : this, how- 
 ever, is not a fixed rule. Where there are a great many 
 dimensions they are placed on all sides and often across 
 the view itself when it does not confuse the drawing. In 
 any case, the dimensions should not be crowded too close to 
 the lines which represent the various views. 
 
 Figure 6 illustrates the proper method of putting in dimen- 
 sions. A short dash and a longer one are put in, these being 
 called '^ witness or projection lines." Then lines, called 
 *' dimension lines,'' are drawn from the centers of the longer 
 dashes, and the dimension is put in at about the center, as 
 shown. Arrows are drawn at the points where the dimension 
 lines touch the witness lines. The tip of the arrow should 
 just touch the witness line. In the case of the 2'' dimension 
 shown in the illustration, the distance is indicated as being 2" 
 from the point of one arrow to the point of the other ; and, 
 
MECHANICAL SKETCHING 
 
 II 
 
 as the witness lines are the same distance apart as the ends 
 of the block, the dimension shows the block to be 2" long. 
 Often, as in the case of the \" dimension, there is not sulBS.- 
 cient room between the witness lines for both the dimension 
 and the dimension lines, in which case the dimension is put 
 inside and the dimension lines and arrows outside the wit- 
 
 FlGURE 6. 
 
 ness lines ; but the meaning is the same. It is f ^' from 
 the tip of one arrow to the tip of the other, whether the 
 arrows are on the inside or on the outside of the witness 
 lines. In still another instance where there is very little 
 room between the witness hnes or between two lines whose 
 distance apart is to be given, both dimension lines and 
 arrows and the dimension may be put outside the two 
 lines, as shown in the \'' dimension. Fig. 7. The f dimen- 
 
12 
 
 ESSENTIALS IN MECHANICAL DRAWING 
 
 sion, shown in the upper right-hand corner of Fig. 6, shows a 
 method of putting in a dimension very common with be- 
 ginners, but one which is not considered the best practice. 
 How to make the arrows. — The arrows are not so easy to 
 make as one might think. Properly made, they are at 
 least twice as long as they are wide at the barbs, and are 
 
 
 
 
 
 
 
 8 
 
 
 2. 
 
 
 7 ^- 
 
 
 ^ \ 
 
 
 W/,.,. ^ 
 
 
 
 
 
 
 5. ' 
 
 
 G. ' 
 
 Figure 7. 
 
 made slightly curved, as shown by arrow i, Fig. 7. Arrow 
 
 2 is in common use. It is made more easily, perhaps, but 
 it is not so artistic and might lead to confusion where a 
 number of witness lines or lines of the drawing are very 
 close together. It has the objection also that it is likely to 
 be the first thing that catches the eye at the first glance over 
 a drawing, whereas the views should be first seen. Arrow 
 
 3 is not symmetrical about the dimension line. Arrows 4 
 
MECHANICAL SKETCHING 1 3 
 
 and 6, shown in Fig. 7, illustrate incorrect shapes. Arrow 5 
 shows a very common mistake made by beginners in draw- 
 ing, — that of not having the point of the arrow touch the 
 witness line. Before starting a drawing make a dozen 
 or more arrows, trying to make them as nearly as possible, 
 symmetrical with respect to the dimension lines. There is a 
 tendency on the part of beginners to make the arrows too 
 heavy on account of the fact that they cannot at first be put 
 in by a single stroke of the pencil, but must be gone 
 over several times in order to get the proper shape. In 
 making arrows, therefore, make the strokes of the pencil 
 very light, and avoid making the arrows too large and 
 prominent. 
 
 Relation of border line to views. — When beginning a 
 sketch of an object, first figure out the size of the views 
 according to the scale to be adopted, and try to get the views 
 in the center of the paper. It is customary to put in a 
 border line which is first put in very lightly ; then if the 
 various views do not come quite in the center of the border 
 line as desired, and if there is plenty of paper outside the 
 border line for trimming, it can readily be shifted- a Kttle 
 in any direction desired. The border line acts as a frame 
 around the object shown, and for that reason should be made 
 heavy, the heaviest weight line of any on the drawing. In 
 some civil engineering drawings and in map work, two lines 
 are often drawn and fancy corners are put in. Do not let 
 any part of the drawing or the lettering touch the border 
 line, and do not put printing outside the border line. 
 
14 
 
 ESSENTIALS IN MECHANICAL DRAWING 
 
 Penciling. — At first make the pencil lines of the drawing 
 very light ; then when the drawing is completed and one is 
 sure that there are no mistakes, the hnes can be gone over 
 again and made heavier where they are not to be inked-in. 
 This practice will save a good deal of erasing, and, there- 
 fore, will save time as well as assist in securing neatness, 
 which is an important consideration in any kind of drawing. 
 Heavier lines make a drawing stand out more clearly and 
 give a much better appearance. The witness Hnes and 
 
 dimension lines should 
 always be put in much 
 Kghter than the lines of 
 the drawing. When 
 looking at a properly 
 constructed drawing 
 the first thing that the 
 eye should see is the 
 drawing itself, because 
 of its greater weight of line ; then, as a secondary con- 
 sideration, the eye sees the witness and dimension lines 
 and arrows. 
 
 Putting in curves. — When a corner in the view is to be 
 rounded off, it is properly done by one of two methods. 
 Suppose a right-angled corner is to be rounded with a curve 
 of \" radius. Set the compass to i". Place the point at 
 the corner a (Fig. 8), and strike off two arcs on the lines 
 forming the corner. Then, with these intersections as 
 centers, and with the same radius, strike off two arcs which 
 
 Figure 8. 
 
MECHANICAL SKETCHING 1 5 
 
 meet at b, which locates the center for drawing the i" 
 curve. Where the Hnes do not form a right angle, the 
 method of procedure is somewhat different. If, as in Fig. 
 8, a i^' radius is required, draw light hnes parallel to and 
 "g-^' from the lines on which the curve is to be drawn. The 
 point c at which they meet is the center* for the curve. 
 This last method can be used with the right-angle corners. 
 
 When to use a solid or dotted line. — The following is a 
 very good rule for the beginner to keep in mind when working 
 on a mechanical drawing. Whenever two plane surfaces 
 meet, forming an edge on the side of the object shown in 
 the view, there is a solid line in that view. It makes no 
 difference whether the surfaces meet at a right angle or at 
 any other angle. If the two surfaces do not meet, making 
 an edge, but rather round off with a considerable curve, 
 then no line is shown except where one of the plane surfaces 
 is parallel to the line of sight. Where two surfaces meet, but 
 on the far side of the object so that the eye cannot see the 
 intersection, the soUd line is not drawn but a dotted line 
 is used, as shown by line 7, Fig. 7. These rules are very 
 important, and a careful observation of them will assist 
 greatly in mechanical drawing. 
 
 How to make hidden lines. — In making these dotted 
 lines, called " hidden lines '' or " invisible lines,'' the dots, 
 or rather dashes, must not be made too small nor too 
 large. In ordinary drawings the dashes are made about 
 one eighth of an inch long ; on large scale drawings a little 
 longer, and on the small scale drawings they should be made 
 
1 6 ESSENTIALS IN MECHANICAL DRAWING 
 
 shorter. In any case the dashes should be all of the same 
 length. The spaces between the dashes should be uniform 
 and should not be more than one half the length of the 
 dashes. Hidden lines should not be made as heavy as Ihe 
 solid lines of the view. 
 
 Center lines. — When drawings are made of cylindrical 
 or partly cylindrical objects, a center line is drawn in the 
 side view through the center of the cylindrical part, and 
 extends on through the end view of this part. Line 8, 
 Fig. 7, shows the proper center line. 
 
 Breaking dimension lines. — If the dimension lines are 
 very long, it is a common practice to break them up into 
 two or even three long dashes, but this practice should not 
 be carried too far. It is very seldom that more than two 
 dashes should be put in as dimension lines on either side 
 of the dimension. 
 
 Putting in large dimensions. — Where the dimension is 
 greater than 36 inches, the length of the carpenter's rule, 
 it is often not put down in inches, but in feet and inches. 
 For example, 79 inches would be shown on the drawing as 
 6' — 7". A very common mistake is to leave out the dash 
 between, thus 6'f'. The objection to this practice is that 
 the workman who might be making the object from the 
 drawing is apt, in the hurry of the work and the possible 
 worn condition of the much-used copy of the drawing, to 
 make a mistake and make the object 67'' instead of 79'' 
 long. The writer recalls seeing mistakes of this kind 
 which usually proved expensive. When making drawings 
 
MECHANICAL SKETCHING 1 7 
 
 to be used by workmen, make it a practice to give every 
 necessary dimension, for if it is necessary to add or sub- 
 tract other dimensions to get what is wanted, there is 
 always a chance of an error which might be costly. 
 
 The printing in of dimensions, explanatory notes, and 
 the title constitutes the last, but by no means the least 
 important, part of the drawing. Long after the beginner 
 has acquired considerable faciUty in the making of good 
 drawings, his lettering and figures will betray his inexperi- 
 ence. 
 
 Lettering. — There are four important things to be kept 
 in mind when lettering. The first point is to have all the 
 letters of a uniform height. In order to accomplish this 
 readily, it is necessary to draw parallel lines to indicate the 
 desired height of the letters or the figures. These lines 
 should be drawn as lightly as possible, especially in case the 
 drawing is not to be inked-in afterwards or traced for blue 
 prints. By the use of the parallel lines the height of letters 
 is sharply defined and there is no difficulty in getting uni- 
 formity in this regard. 
 
 The second item is that of making all the letters or figures 
 of the same slant. In the system of lettering which is to 
 be used (Fig. 9), the letters and figures are to be made with 
 a slant of about 30 degrees from the vertical. It has been 
 found that the slant system of lettering can be printed much 
 faster than the old vertical system. On account of this 
 fact, the tendency in modern mechanical drawing is to 
 throw aside the old vertical system and more and more to 
 
1 8 ESSENTIALS IN MECHANICAL DRAWING 
 
 use the slant. There is another reason for the use of the 
 slant system of lettering. A little difference in the slant 
 of the letter or figure is not nearly so noticeable as a corre- 
 sponding difference where the vertical system is used. The 
 eye seems naturally to be trained to notice anything that 
 is out of the vertical, but a slight variation in any given 
 slant is not so readily observed. 
 
 Sffi^E^^^ 
 
 n.hrflt->lnf)nklrrir)nrrq-r 
 sl ij \/wyy/ 
 
 Figure 9. 
 
 Some difficulty is experienced by beginners in getting the 
 proper slant for such letters as X and F. The easiest 
 method of accomplishing this at the start is to draw a light 
 line at the proper slant, representing the center of the 
 letter, and then to make the letter symmetrical about this 
 line. 
 
 The third thing to be kept in mind in developing a good 
 system of lettering is the item of spacing. This requires 
 considerable care at the start ; but, after some experience 
 has been gained, letters and figures will be properly spaced 
 
MECHANICAL SKETCHING 1 9 
 
 without much thought. The letters should not be put in 
 at an equal distance apart, but the distance between the 
 letters should be such that the space or area between the 
 letters is equal. To illustrate, — the capital letters L and 
 M must be as close together as possible where the L pre- 
 cedes the M , in order to get anything like uniform spacing. 
 A glance at the sample lettering will show the necessity for 
 carefully considering the spacing on account of the in- 
 equality in shape of the various letters and figures. In 
 Fig. 9, the spacing between the capitals F and G is too 
 great. 
 
 The fourth requirement is that the letters and figures 
 should have the same weight or thickness of line. This is 
 essential, not only in the more difficult work of inking-in 
 letters and figures, but also in the pencil work. In ordi- 
 nary lettering for mechanical drawings, no attempt is made 
 to shade either letters or figures. 
 
 The main objects to be kept in mind in learning lettering 
 for mechanical drawings are simplicity and speed as well as 
 good appearance and clearness. 
 
 Figure 9 shows a system of lettering that is in very common 
 use. Note the simplicity of the letters. There are no 
 extra curves, only just enough to indicate the letters. This 
 type of lettering is clear cut, can be read easily, and can 
 be penciled in with speed when once mastered. As in 
 any system of lettering, the exact shape of the letters must 
 be memorized. To this end it is well to have at least one 
 memory test in lettering the alphabet early in the drawing 
 
20 ESSENTIALS IN MECHANICAL DRAWING 
 
 course in order to be sure that the proper shapes are being 
 acquired right from the start. 
 
 For ordinary drawings, the capitals and the higher of 
 the smaller letters are made i^e'' high, while the smaller 
 letters are put in ^^^ high. The proper proportion is to 
 make the body of the small letter three fifths the total 
 height of the letter. For example, the body of the small 
 letter b is three fifths of its total height. This, however, 
 is a proportion which is rather hard to get, and the propor- 
 tion of i and t6 works out very well and, if anything, 
 gives a bolder and -more rounding shape to the letter. The 
 possible criticism to the letters and figures shown is that 
 they are not broad and full enough. This is more ap- 
 parent in connection with the capitals and the figures. 
 
 In putting in dimensions, the figures are ordinarily 
 printed i'' high. If a fraction is used, each figure in the 
 fraction is sometimes printed a little smaller, about -^ of an 
 inch in height, three quarters the height of the full number. 
 
 Good lettering cannot be done with a dull or very soft 
 pencil. Sharpen the pencil to a long point and have a 
 small piece of fine sandpaper at hand for keeping the point 
 in good condition. It is of equal importance to keep the 
 pencil sharp when making the drawings. 
 
 Titles. — The title of a drawing is variously located. 
 The ordinary drafting office practice is to have the title at 
 the lower right-hand corner. Figure lo shows a simple form. 
 The name and date are i^" from the lower border line. The 
 lettering has yi^" spaces between. The name of the object 
 
MECHANICAL SKETCHING 21 
 
 shown in the drawing is put in capitals ^ while in the case of 
 the name, the scale, and the date, small letters are used. 
 Often the title is located above the view or views as in case of 
 Fig. i8 and Fig. 20; and sometimes it is placed in the center 
 of the paper directly below the views as in Fig. 17. The im- 
 portant thing to be kept in mind when penciling in the title 
 
 TABLE BOOK RACK 
 
 Scale: g"^ /'. 
 
 v>|<e 
 
 '^Name.^ Date. 
 
 K)|C3 ♦^ 
 
 Figure 10. 
 
 is to make it symmetricaL If, as in Fig. 10, a center line 
 were drawn vertically through the center of the name of the 
 object, the line being equally distant from T and K^ the 
 other words in the title should be symmetrical about this 
 center line. In the figure, the capital letter N in ^^Name^' 
 will be as far from the center line as the small letter e in 
 " Date." No matter where the title is located, this prac- 
 tice should be followed. 
 
SUGGESTIVE OUTLINE FOR A SHORT COURSE 
 IN DRAWING, USING PENCIL AND RULER 
 
 Drawing periods. — There should be one drawing period 
 a week if home work is given, or two periods without home 
 work. Drawing periods should be one and a half to two 
 hours, preferably two hours ; each drawing to be done in 
 one period, except the House Plans, which would require two 
 or three periods. In case hour periods have to be used, 
 two such periods would equal one of the longer ones. 
 Definite instructions, by means of a rough sketch on the 
 blackboard as to the location of the views in relation to the 
 border line and a few of the main dimensions, will save 
 much time. See Fig. ii. 
 
 Kind of paper to use. — If the drawings are to be done 
 with a rule and pencil only, the edges of the paper used 
 must form a rectangle with square corners, as the main 
 outline of the drawing will have to be put in by measuring 
 from the edges of the paper. A good quality of fairly heavy, 
 smooth, white linen bond paper, 8i'' X ii'', is satisfactory 
 for these exercises, or, better still, pads of the heavier white 
 drawing paper of about the same size, or preferably a 
 little larger, which can be had through the bookstores. 
 The drawing can be done on any smooth table or desk; 
 
OUTLINE FOR A SHORT COURSE IN DRAWING 
 
 23 
 
 sometimes it helps to have an extra sheet of paper under- 
 neath. 
 
 DRAWING EXERCISES 
 
 Exercise i. — • (Home work.) Hand in a copy of the 
 sample lettering in lead pencil, on a specified size sheet of 
 
 Figure ii. 
 
 paper, or on a small uniform size sheet given out for the 
 purpose. Make height of letters and figures the same as 
 in Fig. 9. 
 
 Exercise 2. — Make a mechanical drawing of the half 
 dovetail joint, using the dimensions in Fig. 3 and showing 
 
24 
 
 ESSENTIALS IN MECHANICAL DRAWING 
 
 top and side views as in Fig. 12. Use the scale, 6'' =1'. 
 Put in all hidden Unes. Put in a border Kne i'' from the 
 edge of the paper. Put title in lower right-hand corner, 
 following the method shown in Fig. 10. Get the views in 
 
 the center of the paper. 
 Exercise 3. — (Home 
 work.) Hand in an iso- 
 metric drawing of the 
 half dovetail joint. Scale, 
 6'' = i'. Put in all di- 
 mensions, but do not 
 put in a border line or 
 show hidden lines. Title 
 and its location as in 
 Exercise 2. 
 
 Exercise 4. — Make a 
 half size isometric draw- 
 ing of the mortise and 
 tenon joint from Fig. 13, border i'' from the edges of the 
 paper, title at the top as in Fig. 3. Draw all hidden lines, 
 but not the parts of the joint separately. 
 
 Exercise 5. — (Home work.) Hand in an isometric 
 drawing of a bench hook (Fig. 14). Do not use a border 
 line. Put title in lower right-hand corner. This bench 
 hook is made from one piece of wood. Read over the notes 
 on isometric drawing, beginning on page 5. 
 
 Exercise 6. — Make a mechanical drawing of the 
 blacking stand shown in Fig. 15. Scale, 3'' =1'. Border 
 
 Figure 12. 
 
OUTLINE FOR A SHORT COURSE IN DRAWING 
 
 25 
 
 line, f X 10^'. Draw the views f from the side border 
 lines. The body of the box is 16'' long and 11'' wide. 
 Make the stand a convenient height for use. Work out 
 all dimensions. On a separate sheet of paper hand in a 
 
 - — H^— 
 
 
 h-^^'H 
 
 1 ' "0103 
 
 i 
 
 l-/#--l 
 
 Figure 13. 
 
 bill of the material required to make the blacking stand, 
 using the form given below. The pieces must be of dimen- 
 
 Name of Object 
 Kind of material To he finished with 
 
 
 No. OF Pieces 
 
 Thickness 
 
 Width 
 
 Length 
 
 
 
 
 
26 
 
 ESSENTIALS IN MECHANICAL DRAWING 
 
 sions large enough to allow for finishing to required size 
 in the wood shop. For example, a 12'' board would be 
 used for the vertical end pieces; in actual practice the 
 
OUTLINE FOR A SHORT COURSE IN DRAWING 
 
 27 
 
 J board will be about iif wide. Timber is sold as 6", 8", 
 10'', 12'', 14'', etc., wide, but when actually measured it 
 
 I usually is i^^ less. A i^' finished board is actually about yf " 
 thick. In the rough it is about i" thick. An ordinary 2'' 
 
 Figure 15. 
 
 X 4" finished on all sides (S2S) is actually about if" X 
 3f " ; the 2" X 6" is if X 5f ". These points must be 
 kept in mind when planning the dimensions of wooden 
 objects in order to economize in material. Many good 
 draftsmen neglect this important matter. 
 
28 
 
 ESSENTIALS IN MECHANICAL DRAWING 
 
 Exercise 7. — (Home work.) Hand in a mechanical 
 drawing of the wooden work basket, a suggestive outline 
 of which is shown in Fig. 16. It is 26'' high and 14'^ square. 
 Scale, 3'' =1'. No border line. Material, oak. Draw a 
 side and a top view. Put title in lower right-hand corner. 
 
 Exercise 8. — 
 Make a mechanical 
 drawing of a poultry 
 feed hopper (Fig. 17). 
 Scale, 3^' =1.' Use 
 no border line. In 
 this case there is not 
 sufficient room on 
 the 8i X ii'^ paper 
 to show the entire 
 side view ; part of 
 the middle is, there- 
 fore, taken out, as 
 shown by the broken 
 lines. This is often 
 
 done in drawings of 
 
 Figure 16. long objects of uni- 
 
 form size and shape. As the slanting board cannot be 
 seen, except by hidden lines, in an end view, a sectional 
 view is shown as if the box were cut away at ^ — B, Put 
 in title as in Fig. 17. 
 
 Exercise 9. — (Home work.) Hand in a mechanical 
 drawing of the table bookrack (Fig. 18) on cross-section 
 
OUTLINE FOR A SHORT COURSE IN DRAWING 
 
 29 
 
 K#fH 
 
 71 
 
 
 
 ^^,^^ 
 
 
 1 
 1 
 
 1 
 1 
 1 
 1 
 -d 
 
 L\ 
 1 
 1 
 1 
 
 
 5 i 
 
 f 
 ____ 
 
 
 >o\^ 
 
 
 
 1 
 
 
 
 
 1 
 
 
 
 1 ^ 
 
 ^ 
 
 Xj 
 
 
 
 ^ 
 
 iJ 
 
 QD 
 
 Ji 
 
 -V 
 
 
 •<) 
 
 .^ 
 
 
 > 
 
 1 ^ 
 
 (} 
 
 1 
 
 ! 
 
 <>! 
 
 
 paper. If the squares are 16 to the inch, let 4 squares 
 equal i inch. If the paper has 8 or 10 squares to the inch, 
 let 2 squares equal one inch of the object. 
 
30 
 
 ESSENTIALS IN MECHANICAL DRAWING 
 
 Cross-section paper is very useful for the rough sketching 
 of objects, and particularly for making preliminary plans 
 of barns or houses. Let agricultural students, instead of 
 drawing the table bookrack, make a drawing of the gambrel 
 
 TABLE BOOK RACK. 
 Scale:^a^- / /nch Name 
 
 /^ 
 
 A 
 
 r"ii 
 
 n 
 
 Figure i8. 
 
 roof with bracing, as shown in Fig. 19. Draw foundation 
 I foot thick. Scale, ^' =1'. Put the following title below 
 the drawing : — 
 
 METHOD OF BRACING GAMBREL ROOF 
 
 Scale 
 
 Name_ 
 
 Date_ 
 
 The figure gives a fairly good idea of one method of fram- 
 ing the gambrel roof. It also gives a good proportion for 
 such a roof, the rafters being equal in length, and the cuts 
 easy to work out. The sketch is for a 36' barn. The 
 studding, rafters, and braces forming the bent are all 
 2 X 6's. There are two kinds of framing, one on each side 
 of the center line. The bent shown on the left side is put in 
 
OUTLINE FOR A SHORT COURSE IN DRAWING 
 
 31 
 
 every fifth or sixth rafter, and of course is the same on both 
 sides of the peak, only one half being shown in the cut. The 
 sets of rafters between these bents are tied together as 
 shown on the right side, with i '' X 6'' stuff. The hay track 
 
 Figure 19. 
 
 can be hung from the intersection of the scissors truss, if 
 desired, or a 2'' X 6'' collar tie can be used at the same 
 , level as the intersection just mentioned. The lower 2" X 
 6^' brace, that projects out into the loft at the bottom, is not 
 always used, as it cuts up the loft to a certain extent. It 
 would not necessarily have to extend out as far as shown. 
 
32 ESSENTIALS IN MECHANICAL DRAWING 
 
 In wide barns the brace should not be left out. Often 
 two studs are used at each bent, and it is a good practice 
 when building barns much over 30 feet in width and 
 height. 
 
 Exercise 10. — (For boys.) Make a copy of the plan 
 of a barn shown in Fig. 20. Scale, |'' =1'. Make the 
 outside walls i foot thick. Put title in center above the 
 plan. 
 
 Figure 20 shows an excellent type of dairy barn. It is 
 the plan of the model dairy barns used on the Alberta 
 Experimental Farms located in different parts of the Prov- 
 ince. The plan shows a central feed room in the most 
 convenient relation to the feed alleys. The grain bins 
 are overhead in the loft. The plan can be readily extended 
 or rearranged. If one wanted an inclined driveway into the 
 loft, it could easily be arranged just outside the bull pen, or 
 at the opposite end of the feed passage. A root cellar could 
 then be put under the incline. It could be extended to 
 the left enough to take in the feed passage, thus affording 
 a convenient entrance to the root cellar. If desired, a 
 concrete milk room could be put under the driveway. The 
 cross feed passage at the end makes it very easy to put on 
 an additional wing at either side, making an L-shaped 
 barn, with the added space available either for more cow 
 stalls, or for a horse barn, if so desired. Again, a root cellar 
 might be placed at one end of the cross passage, and a silo 
 at the other ; the silo being placed on the sunny side of the 
 barn. The farmer might cut down the width a little, if 
 
OUTLINE FOR A SHORT COURSE IN DRAWING 
 
 33 
 
34 ESSENTIALS IN MECHANICAL DRAWING 
 
 he SO desired, by economizing in the width of the feed 
 passages. The barn has the gambrel roof that is being 
 used so widely in modern barn construction. 
 
 (For girls.) Copy two plans of the model kitchens in Fig. 
 21. Scale, j^ = i\ Put title ''Model Kitchens/' etc., 
 in lower right-hand corner. 
 
 The kitchen is said by many women to be the first con- 
 sideration in house planning, since it is the part of the house 
 where they do a large part of their work and where there 
 is the greatest necessity for convenience and comfort. It 
 should, therefore, be carefully thought out, and there should 
 be no great difficulty in securing a house plan that the 
 kitchen will fit into. If the house is planned without par- 
 ticular thought about the requirements of the kitchen, it 
 often develops that the rest of the house will not admit 
 of a convenient kitchen lay-out. 
 
 The suggestive plans in Fig. 21 are from well-known 
 women writers on household science. Plan i is from the 
 Efficient Kitchen by Georgie Boynton Child. Plan 2 is 
 from The Farm Kitchen as a Workshop, U. S. Farmers' 
 Bulletin No. 607, by Anne Barrows. Plan 3 is from Mrs. 
 Fredrick's book The New Housekeeping, This is an espe- 
 cially suggestive plan, as it shows by arrows the cycle of 
 operations in the preparing of food for the table, and the 
 washing and putting away of the dishes after the meal is 
 finished- The kitchen in the plan shown in Fig. 22 is one 
 which allows for good light and air as Well as for convenience. 
 Make the kitchens whatever size you consider best for your 
 
OUTLINE FOR A SHORT COURSE IN DRAWING 
 
 35 
 
 
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 ^ 
 
 /^'-/9'o\ 
 
 
 ^j9^A 
 
 
 
 c^ 
 
 / 
 
 
 ^ 
 
 
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 J5 
 
 ;: 
 
 
 k t^-^ 
 
 5 
 
 ^5 
 
 1 
 
 t\ \^ 
 
 
 
 
 
 
 
 -^ 
 
 •0 
 
 
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 ' 
 
 . 
 
 1 
 
 
 %J.^ 
 
 
 
 
 "t^ 
 
 
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 .Q 
 
 ^^ 
 
 ^_ 1 
 
 
 ^" 
 
 
36 ESSENTIALS IN MECHANICAL DRAWING 
 
 home conditions. The dimensions of kitchen furnishings 
 on page 38 will be of assistance. 
 
 Exercise ii. — (Home work.) Hand in a mechanical 
 drawing showing side and end views of a table, bookcase, 
 or dresser. Scale, iV = i\ If there is room, put in a 
 border line. Draw a line representing the floor on which the 
 object rests. Put title below the view. 
 
 Exercise 12. — Copy the floor plan of bungalow shown 
 in Fig. 22, or some other plan of a bungalow or house. 
 Use the scale, j^ = i'. 
 
 In drawing floor plans of a wooden house, make the walls 
 6'^ thick — both outside and partition walls. Single 
 windows are 28'' to 30'' wide ; large front windows are 3^' to 
 4' wide. The front door is usually 36'' wide ; the outside 
 kitchen door 30'' ; the double swinging door between the 
 kitchen 28'' to 30'' ; doors to bedroom closets 24'' ; door 
 to bathroom 26'' to 28'', and other doors 28". These are 
 average sizes, though there is considerable variation. 
 
 Stairs vary widely in dimensions. Where there is room, 
 a very good stair is one with a 7'' rise, and a 10'' tread. A 
 7^" rise and a gi'' tread gives an easy running stair. Cellar 
 and attic stairs are steeper, in many cases the rise and tread 
 being equal, as 8^'^ for both rise and tread. 
 
 In house planning, doors are usually located in the comer 
 of the room. Doors and windows in bedrooms should be 
 so located as to avoid drafts across the bed. 
 
 Sizes of furnishings. — The following is a list of common 
 furnishings, together with their average dimensions, and 
 
OUTLINE FOR A SHORT COURSE IN DRAWING 
 
 37 
 
 lAJOJ^ 
 
 
 a 
 
 ..TJ 
 
 TZZJ 
 
 " \ — 
 
 «: 
 
 
 P 
 
 
 
 / v^ 
 
 11 
 
 to ^ 
 
 
 q:] 
 
38 
 
 ESSENTIALS IN MECHANICAL DRAWING 
 
 is useful for consideration in planning the sizes of rooms 
 and location of doors and windows : — 
 
 Double Bed 4 
 
 Single Bed 3 
 
 ChHd'sBed 
 
 Dresser 
 
 Dining Room Table 
 
 Living Room Table 
 
 Bookcase 
 
 Piano 
 
 Davenport 2^ X 6 to 7 
 
 Bathtub 2j X 5 
 
 Range 2I X 4 
 
 Kitchen Cabinet 2X4 
 
 Kitchen Sink ij X 2 
 
 Drain Boards to Sink li X 2 
 
 Refrigerator if to 2 X 2^ 
 
 to 4^ X 6 
 to 3i X 6 
 2^ X4i 
 if X3i 
 3^X6 
 
 iiX3i 
 
 2iX 5 
 
 feet 
 feet 
 feet 
 feet 
 feet 
 feet 
 feet 
 feet 
 feet 
 feet 
 feet 
 feet 
 feet 
 feet 
 feet 
 
MECHANICAL DRAWING WITH REGULAR 
 DRAWING EQUIPMENT 
 
 Equipment. — For this work, the following equipment is 
 necessary : drawing board i8" X 24", a T square, a 30°- 
 60^ triangle, a 45° triangle, a draftsman's triangular 
 
 Figure 23. 
 
 scale, some thumb tacks, a bottle of Higgins' black ink, a 
 set of drawing instruments, and a pencil and eraser. A 
 small set of drawing instruments that will do very well 
 can be purchased for about $3. Figure 23 shows such 
 a set of instruments which consists of a ruling pen, a small 
 combination bow compass and pencil, a pair of bow dividers, 
 a large compass with a pen and a pencil point and an 
 
 39 
 
40 ESSENTIALS IN MECHANICAL DRAWING 
 
 extension bar for large circles, and a protractor. The rest 
 of the drawing equipment will cost about $3 more. To 
 avoid confusion, it is highly desirable that the students 
 should put their initials on their equipment. 
 
 The left edge of the drawing board must be true, for 
 the head of the T square slides against this edge. Drawing 
 boards, when first purchased, generally need '' truing-up '' 
 on the edge with a jointer plane. The T square, sliding 
 against the edge, is used for making all horizontal lines, 
 while the triangles, resting against the blade of the T square, 
 are used for making all vertical lines. Draw horizontal 
 
 Figure 24. 
 
 lines with the pencil against the upper edge of the blade of 
 the T square. Figure 24 shows the drawing board with T 
 square, 30^-60° triangle, and drawing paper, ready to 
 begin work. 
 
 Steps in penciling and inking drawings. — i. Put draw- 
 ing paper on center of board, fastening with four thumb 
 tacks, and having horizontal edges parallel to blade of T 
 square. 
 
DRAWING WITH REGULAR DRAWING EQUIPMENT 41 
 
 2. Draw border line lightly to required size. 
 
 3. Lay out position of views, keeping in mind position 
 of title. 
 
 4. Draw main lines of views. 
 
 5. Draw hidden or invisible lines. 
 
 6. Put in witness and dimension lines. 
 
 7. Put in dimensions and arrowheads. 
 
 8. Print in title, and notes if any. 
 
 9. Ink-in border line heavy, 
 
 10. Ink-in curves. 
 
 11. Ink-in views. 
 
 12. Ink-in witness and dimension lines. 
 
 13. Ink-in dimensions and arrows. 
 
 14. Ink-in title and notes. 
 
 Inking-in drawings. — The best ink for this purpose is 
 Higgins' Carbon Waterproof Ink. There is also Higgins' 
 Black Ink which is not waterproof. The latter is just as 
 good except for the reason that sometimes one may be 
 carrying a drawing on the board exposed to the air, and a 
 few flakes of snow, or drops of rain, may fall on it, in which 
 case the ink which is not waterproof softens and, if rubbed 
 in that condition, will spread and spoil the drawing. 
 
 Always keep the stopper in the bottle, as it keeps out 
 the dust and prevents accidents if the bottle is tipped 
 over. When filling the pen by the use of the stopper, do 
 not perform the operation above the drawing, as there is 
 always danger of dropping some ink ; nor should one fill 
 the pen too full nor allow it to get entirely empty. 
 
42 ESSENTIALS IN MECHANICAL DRAWING 
 
 The first care in inking-in drawings is that the surface 
 be free from dust, particles of eraser, lint, etc. Any such 
 material is caught up by the pen and will change the 
 thickness of the line. Next, and equal in importance, is 
 the care of the inking pen, whether it be for the compass or 
 for the straight line work. The pen must always be free 
 from ink, either wet or dry, on the outside surfaces of the 
 two points, and from dry ink on the inside surfaces. Under 
 no circumstance should ink be allowed to dry in the pen. 
 The piece of linen which comes around the ink bottle is 
 for cleaning the pen, but any cloth free from lint will do. 
 
 Before starting to ink the first drawing, examine the points 
 of the pen ; they should be sharp and of equal length. %In 
 case they are not, make them equal by rubbing them on 
 an oilstone. To tell whether they are in good shape, screw 
 the points almost together and hold them up to the light. 
 When inking, tip the handle of the pen about thirty degrees 
 from the vertical (Fig. 25) in the direction in which the 
 line is to be drawn, but keep the pen in the vertical plane 
 which passes through the line so that both points of the pen 
 rest with equal pressure on the drawing paper. If one point 
 touches and the other does not, the line drawn will be 
 ragged and rough on the side where the point of the pen does 
 not touch. Careful attention to this principle will greatly 
 improve the work of beginners. 
 
 Use of compass. — When inking with the compass ob- 
 serve the rules just given. Hold the compass lightly at 
 the extreme end between the thumb and first or second 
 
DRAWING WITH REGULAR DRAWING EQUIPMENT 43 
 
 finger and make the circular motion by rolling the end of 
 the compass between the surfaces of the thumb and finger. 
 Do not press down hard. When there are curves to be 
 inked-in on a drawing, always ink them first. It is far 
 easier to ink-in a straight line to meet one end of an inked 
 curve, than to ink-in a curve to meet two straight lines. 
 
 Inking on transparent linen tracing cloth is a little more 
 difficult operation than working on paper. The glazed 
 
 Q 
 
 
 Figure 25. 
 
 surface does not take the ink so readily and the ink does 
 not dry so quickly. Many consider it preferable to ink 
 on the glazed side, as there is more starch on that surface, 
 which permits erasing. Before starting to ink, rub an 
 ordinary blackboard eraser over the glazed surface so 
 that it will take the ink more readily. Be careful to 
 wipe off the chalk before beginning to ink. The majority 
 of draftsmen prefer to use the dull side, as it takes the ink 
 better. 
 
SUGGESTIVE LIST OF EXERCISES FOR A SHORT 
 COURSE IN DRAWING WITH INSTRUMENTS 
 
 This course will require twenty two-hour drawing periods, 
 one period a week. It is well to set a definite time for each 
 exercise to be finished, in order that those a little behind 
 may catch up with the rest. All exercises to be inked-in. 
 
 Exercise i. — Hand in a copy of the sample lettering 
 on a piece of drawing paper 6'' X 8", with a border line 
 4'' X 6''. Make letters same height as in the copy. Print 
 name at lower right-hand corner inside the border line. 
 Use light pencil fines to guide when lettering, and erase 
 them after the ink is dry. This exercise is to be done out- 
 side of the regular drafting periods. 
 
 Exercise 2. — After laying out Fig. 26 very carefully 
 with a sharp lead pencil, start inking it. The large square 
 is 5'' each way and is divided into 2^'' squares. The lines 
 are all spaced \'' apart at the edge of the squares. To get 
 good results, the laying out of the squares and the spacing 
 must be done very accurately. The beginner may spoil 
 the first drawing, but that is to be expected. Finish the first 
 drawing as carefully as possible, even if some parts are not 
 satisfactory, as the exercise is for the purpose of giving 
 experience in the use of the pens. This experience gained 
 
 44 
 
SHORT COURSE IN DRAWING WITH INSTRUMENTS 45 
 
 on a small drawing will prevent one's spoiling a more 
 complicated drawing later on. 
 
 After the first set of squares has been filled in carefully, 
 make a second drawing of the squares. The beginner 
 should now have sufficient experience from the first trial 
 to do some good inking on the second drawing. When 
 
 Figure 26. 
 
 inking-in the lines that converge to the upper right-hand 
 corner in the upper left-hand square, ink the lines to 
 within about |'' of the corner; then when all the lines 
 have been inked-in, the part not done can be completed. 
 By following this method the point at the upper right- 
 hand corner will not be lost, and the work can be more 
 accurately done. Ink-in the outside of the squares after 
 all the other work is completed. Hand in this exercise on 
 
46 
 
 ESSENTIALS IN MECHANICAL DRAWING 
 
 a sheet 6'' X 8'' without a border line and with name 
 neatly printed in ink in lower right-hand corner. 
 
 Exercise 3. — Make a full-size drawing of the wooden 
 float in Fig. 27. Size of border line 11'^ X I5'^ Trim the 
 
 
 
 
 
 
 
 
 
 
 '!5|o 
 
 
 
 
 
 
 
 
 c\" , 
 
 
 
 
 
 
 i 
 
 
 
 
 
 1 
 
 Figure 27. 
 
 drawing paper to within V of the border line. Put title 
 at top. 
 
 Exercise 4. — Mechanical drawing of blacking stand 
 (Fig. 15). Show side view of stand open and end view. 
 Follow the general directions given in Exercise 6 on page 
 24. Use a border line 11" X 15''. Print out table of 
 material underneath the views. 
 
 Exercise 5. — Make an isometric drawing of the bench 
 hook shown in Fig. 14, scale full size. Ink hidden lines 
 
SHORT COURSE IN DRAWING WITH INSTRUMENTS 47 
 
 Figure 28. 
 
 considerably lighter than the solid lines. Put title in lower 
 right-hand corner. Border line ii'^ X 15''. Trim all 
 drawings to within i'' of the border line. 
 
48 
 
 ESSENTIALS IN MECHANICAL DRAWING 
 
 Exercise 6. — Drawing of work basket (Fig. i6) or 
 umbrella stand (Fig. 28). The work basket is to be 14'' 
 square and 26'' high. The umbrella stand is 12'' x 2^', 
 
 
 
 ♦ 
 
 
 
 f 
 
 
 
 
 
 1 
 
 i 
 
 -fi 
 
 .1 
 
 
 
 5 
 
 
 
 i" 
 
 - 
 
 
 
 
 1 
 
 ' T 
 
 * * r 
 
 ^ 
 
 
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 1 
 
 ^ — fV- 
 
 1 
 
 \ 
 
 «» ri^K 
 
 
 1 
 
 
 
 
 
 
 
 
 
 Vt^-A 
 
 ■=? 
 
 
 
 
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 • *; 
 
 3 
 
 
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 ff<" 
 
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 K 
 
 
 
 
 
 
 
 
 
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 V 
 
 h-- 
 
 ^*H V,. + 
 
 
 5* , 
 
 
 ^i^. 
 
 
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 t 
 
 
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 J"^■^ 
 
SHORT COURSE IN DR.\WING WITH INSTRUMENTS 49 
 
 Use the scale, s''=i' in either case, and the standard 
 border line ii'' X is'' - Show a side view, and top view to 
 the right of the side view. If the student has had wood 
 shop, show the mortise and tenon joints. Show all dimen- 
 
 FlGURE 30. 
 
 sions. Underneath the top view, print the bill of material 
 as already directed. 
 
 Exercise 7. — Make a side and end view of either a work- 
 bench (Fig. 29) or a sawhorse (Fig. 30). The workbench to 
 be drawn to a scale of i''= i^ Often, when objects are 
 
5° 
 
 ESSENTIALS IN MECHANICAL DRAWING 
 
 o 
 
SHORT COURSE IN DRAWING WITH INSTRUMENTS 5 1 
 
 drawn that naturally rest on the floor, a heavy line is 
 drawn to represent the surface of the floor. Border line 
 11'' X 15". Place title above the views. The sawhorse 
 should be drawn to the scale, 3'' = i'. Draw a heavy 
 line to represent the floor. 
 
 Figure 32. 
 
 Exercise 8. — ; Draw side and end views of a portable 
 pig cot (Fig. 31) with part of the roof boards arid siding 
 cut away to show the framing. Scale, f '' = I^ Use the 
 11'^ X 15" border line. Place the title above the views. 
 Figure 3 2 shows the framework of the pig cot. First draw 
 the end view of the frame of the pig cot. The rafters are 
 
52 
 
 ESSENTIALS IN MECHANICAL DRAWING 
 
 f 
 
 l.,.n. r» n ,n_ 
 
 II , - " " II"" 
 
 
 1 
 
 
 . 
 
 I 1 
 
 
 1 
 
 «£f 
 
 tVj 
 
 j&c/c/o^pa9_£ 
 
 
 1 
 
 
 ^ 
 
 
 
 1 
 
 1^ 
 
 
 
 
 I 
 
 ' = 
 
 3 
 
 
 E 
 
 I 
 I 
 
 r/- r/' 
 
 
 
 
 ( 
 
 "N 
 
 
 
 
 
 Y 
 
 ^-V. 
 
 O 
 
 
 
 > 
 
 
 
 
 I 
 
 S^ 
 
 ^ 
 
 
 
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 ?1 
 
 Plan. 
 
 CD - 
 
 
 "^^ (, 
 
 
 \ 
 
 
 
 ^ 
 
 
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 '*', ^ 
 
 - 
 
 n 3'K9 — 
 
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 i u i. u yi 
 
 8' long over all. Then draw in the roof boards, vertical 
 siding, and door. The door is made of two thicknesses of 
 inch lumber, one thickness being nailed on crosswise to the 
 
SHORT COURSE IN DRAWING WITH INSTRUMENTS 53 
 
 other, the outside layer being vertical. The door swings 
 both ways on f '' rods as shown. Having drawn the end 
 view, lead in the side view, getting the heights of the various 
 lines by transferring horizontally across from the end view. 
 
 Exercise 9. — Draw plans of a poultry house 16' x 
 25', showing plan, sectional view, and end and side eleva- 
 tions as in Fig. 33. Use the scale f'' =1'? and make the 
 drawings on paper 18'^ X 24''. Use a border line 15'' X 22'', 
 and trim the paper to within f of the border. The pitch 
 of the roof is xe? the rafters being given a f rise, instead of 
 the half pitch, in order that 12' material may be used for the 
 rafters and still give room for the straw loft. The plan and 
 sectional elevation show the standard layout for nests and 
 roosts for a fresh-air house for 100 hens. Figure :^2> ^^^y ^Iso 
 be followed in planning a house for a smaller number of birds. 
 
 Exercise 10. — Draw stable plan, side and end eleva- 
 tions of a gambrel roof barn, the scale \^\ tV? or J'' to the 
 foot, depending on the size of the barn. Use a sheet of 
 drawing paper 18'^ X 24'^ If possible, use a border line, 
 the size depending on the amount of space the views take. 
 
 Figure 34 will give suggestions as to the proper method 
 of proceeding. First, draw the end elevation, showing the 
 framing of the barn. This is the basis for starting the 
 drawings as well as for the carpenter work. Next finish 
 the left half of the end elevation, showing siding, cornice, 
 corner boards, etc. Then draw the side elevation, trans- 
 ferring the various heights across from the end elevation. 
 The plan of the barn should, of course, be worked out 
 
54 
 
 ESSENTIALS IN MECHANICAL DRAWING 
 
SHORT COURSE IN DRAWING WITH INSTRUMENTS 55 
 
 in detail before the elevations are drawn. The plan is 
 directly below the side elevation. The space below the 
 end elevation can be used for the title, and, if so desired, for 
 details of stalls, ventilation systems, etc. The end eleva- 
 tion gives the proper proportions for laying out the rafters 
 of the gambrel roof. In barns up to 40' or more in width the 
 height of the building is commonly made about equal to the 
 width. In wider barns the height will not equal the width. 
 Exercise ii.^ — Draw the basement and first and second 
 floor plans of a modern house, together with a front elevation 
 of the same. Use two sheets of paper 18" X 24". Draw 
 the first and second floor plans on one sheet and the basement 
 plan and front elevation on the other. Use the scale i" = 1'. 
 Ink the walls in solid black except for windows and doors. 
 Put the title at the top of each sheet. The following is a list 
 of items to be kept in mind when laying out a convenient 
 basement, though in many cases all are not necessary. 
 
 Stairs, Outside entrance, 
 
 Furnace, Cistern, 
 
 Chimney, Pneumatic tank. 
 Soot box in base of chimney, Pumping apparatus, 
 
 Coal bins. Laundry, 
 
 Coal chute, Drying clothes (in winter), 
 
 Wood storage, Vegetable storage. 
 
 Lighting equipment Fruit storage. 
 (gas or electric lights), 
 
 ^ Should the course in drawing not allow enough time for complete 
 plans of a house, the first and second floor plans and basement plan might 
 be worked out to a smaller scale on one sheet of paper, leaving the space 
 in the lower right-hand corner for the title, similar to Fig. 34. Figure 35 
 illustrates the method of laying out the rough plans on cross-section paper. 
 
Figure ^5. 
 
SHORT COURSE IN DRAWING WITH INSTRUMENTS 57 
 
 The grading of drawings. — The three points to be consid- 
 ered in grading drawings, are i, neatness; 2, lettering, figures, 
 dimension and witness lines and arrows ; 3, the actual draw- 
 ings. A very good arrangement is to allow 10 points for 
 neatness, 30 for lettering, etc., and 60 for the drawings. It 
 is a good plan to go over all the drawings, grading them 
 for neatness, then go over them again and grade for the 
 lettering, etc., and finally run through the drawings the 
 third time and grade the drawing.