How to Do Architectural Drawing: A Text Book and Practical Guide for ...

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Foreword

The mission of this book is to teach HOW to DRAW; Not all there is to know about drawing, but things the BEGINNER should know at the beginning. Most of the things that the beginner does not need at the start have been purposely omitted; however, the student who aspires to higher work and is in need of fuller information will find what he should have in books which are to follow this in publication. See After word at end of this book.

It is the authors desire and intent; to cover the subject of Architectural Drawing, comprehensively, practically and clearly.

It may require several books to accomplish this end, (The author is not unconscious of the fact that it seems a somewhat ambitious undertaking, perhaps) and these will be specific; each possessing a measure of individuality, therefore may be regarded as an entirety or taken as a unit in a series; a link in a chain as it were; The ultimate value of which depends upon its strength and suitability for the purpose intended.

r

TO INSTRUCTORS

This book is not intended to supplant the Teacher. It is designed, rather, as an auxiliary help; a tangible guide to assist the teacher in imparting to the student such, technique and detail information as is desirable or necessary the student should have.

It is intended as a book of reference, a ready means by which the minor matters (of major importance) may be learned by the student at his leisure, and the undeveloped mind so trained in fundamental principles.

The Instructor retains his individuality, and is free to present the various problems in the regular course, in such manner as may seem to him best. However, the teacher's work will be much simplified, and advancement of the student facilitated, if not assured, by guiding him or helping to such information as immediate needs may suggest, and by pointing out to the student, at the time of presenting a new problem, such specific reading as should be done by the student in the interim between sessions.

In fact, he shbuld not only require the student to do such reading but should also require that he should come prepared to answer questions concerning the problem in hand.

When the class is assembled for the first time, the instructor should call special attention of all students to page 77 , as to the proper method of securing drawing paper to the board.

SUPPLEMENTAL PROBLEMS should be introduced in connection with the regular course of study : They will be found useful for such students as are more alert than others, those who outrun the others in point of speed, (quick perception and rapid execution). In these supplemental studies, such geometric problems as are most useful to an architectural draftsman should be incorporated and the application of a problem to practical use when explained renders such geometric problem more acceptable to the student as an intellectual pursuit. The suggestive ornament and embellishments make them a more palatable morsel and appeals to such aesthetic sentiment as may be resting dormant in the breast of the embryonic artist.

Contents

Page FOREWORD 5

TO INSTRUCTORS, SUGGESTIVE.: 7

CHAPlElt

I. Tools

A man cannot be expected to do good work unless he has good tools,* he must understand those tools, and he must keep them in good order and condition.

It is not the intent of this book to go into detail description of all desirable instruments or implements for the purpose of the draftsman,! but there are some things that every draftsman should learn, remember and carefully regard.

Drawing Board — He must have a good Drawing-board, one which is true and square on all sides, or at least, the left hand edge and the bottom edge of every board should be perfectly straight from end to end, and the upper arrisj: of each of these edges should be square, it is not necessary they should be absolutely sharp but they should be true and free from irregularities or knicks.

Boards with cleats on the ends are best, they can be trued (with a smoothing plane) more readily and they

*The word "Tools" is used in a broad sense as covering all th% utensils required by a student for First Year work. The term "Instruments" specifically applies to the metalic tools which are usually sold in sets.

t A more detailed description of them will be found in subsequent books of this series which are in course of preparation.

tThe upper angle or corner of the edge.

keep a better edge (more troe) than end grain of the wood.

T-Square — The T-Square is for the purpose of making straight lines, any number of them in one and the same direction, or in other words, "parallel."

T-Squares may be used at either edge of the board if all edges are square and true. If the edges of the board are not true and square each with the other, then the T-Square should be used at one side or edge only, that at the left hand of the board. If only One edge of the board is true, it becomes necessary to use a Set-Square,* (triangle) in connection with the T-square for the purpose of making lines at right angles to the horizontal lines, that is, at an angle of 90 degrees with such horizontal lines, or perpendicularf to them. When the perpendicular lines are long, they may be made with the T-square from the lower or bottom edge of the board, providing that lower edge is true, and square with the left hand edge.

In general practice and for general use, the T-square and the set-square should be used conjointly for the making of perpendicular lines,which is done by plac-

■See "Sti-Square," page 1«.

tA "perpendicuUc line" is not nccoiarilf i Tcrticol line. Tbere ii ing one edge of the set-square against the working edge of T-square thus:

FIG. 2.

A T-square consists of two parts; a Blade and a Head; it is made in the form of a letter T, hence its name. The blade and the head should Be at exact right angles, or an angle of 90 degrees each to the other.* nci. 3.

T-Squares should be handled carefully, if they are not, and are misused, they get "out of square," i. e., the head and blade get out of the 90** angle, rendering it worthless.

Do not use the T-square as a hammer for driving thumb tacks,t or for any other purpose.

Do not use a knife blade or other sharp instrument along the top edge of the T-square blade, for the purpose of "trimming drawings" or any other purpose. . A knick made in the edge of blade by a knife or any other agency, renders the T-square worthless.

*90 . degrees is written thus 90° — the little circle after the figure denoting "degrees." ,- . -

tStudents are inclined to do this.

If the blade works loose from the head in handling y true the one with the other by use of a triangle (set-square) thus; and insert an additional screw or two to secure the head to blade.

K

•

• 1

FIG. 4.

If the T-square blade becomes warped, or in any other way gets out of true, as to its working edge, it will result in curved lines instead of straight lines, or some other defect. In this condition the square is worthless, better throw it away and get a new one even if the defect is but slight.

u

FIG. 5.

Set-Squares — There are two forms of Set-squares or triangles used as aids for drawing purposes. "Set-square" is the common term for these instruments. The term Triangle is a broad one and not so technical, perhaps, as set-square, at any rate there can be no misunderstanding when the latter term is used. Its name implies that the square and associated angles are always set and ready for use without adjustment.

One of the forms is called the 45 degree angle, or set-square.

The other one is called a 30-60-90 degree triangle or set-square.

The 45° set-square is exactly one-half (diagonally) of a perfect or true geometrical square.

The 30''-60*-90'' set-square is exactly one-half (perpendicularly) of a true geometrical equilateral triangle.

FIG. 6.

The first named, or the 45** set-square, is used as a guide for drawing lines at an angle of 45* or 90**, either or both, and such lines may be drawn with this instrument in connection with a "base line" (a horizontal line), a vertical line or a line in any other direction.

no. 7

The 30**-60''-90** set-square is used as a guide in drawing lines, at either of the three angles, to any given line in same manner as is done with the 45** angle.

I]

HG.B.

These two instruments are also called Right Angle Triangles. (The 90*" angle of each being the right angle.)

IS

By sliding the set-square along the blade of T-square, a great many lines at an angle of 45** may be made in the length of the T-square blade, and the lines may be drawn to the right or to the left as shown.

Fife.n

Lines at an angle of 30** with a horizontal line are made as shown in Fig. 8, and at an angle of 45°, 30"*, 60** and 90** with any other line other than horizontal, thus:

By sliding the 60** set-square along blade of T-squaie in same manner as the other squares are manipulated, angles at 60° can be made, and the same applies to the making of lines at 90° by two edges of either of the set-squares. (See Fig. 9.)

French Curve — A French Curve is a flat form of compound curves made in one piece of pear-wood, hard-rubber, celluloid or similar material. The first named are cheapest and best. Their use is to assist in the making of curved lines which cannot be made .with the compass, ^ and which cannot be well made by hand. , (

These curves are made in many sizes and many forms or shapes; however, the draftsman does not need more than two of them provided they have been wisely chosen.

Case Instruments — By "Case Instruments" is meant the regular set of metal tools provided for use of a draftsman. Every student should, from the beginning, have a set of good instruments, cheap tools are a bad investment, they are worthless because good work cannot be done with them, even by an expert. All joints in these tools should be moderately stiff, so they will not shift in position while handling, without effort or undo pressure. If these joints work loose, they should be keyed up by tightening the screws. There is a small screw driver or key in each case of tools made especially for this purpose.

Dividers — ^The two points on a pair of dividers should be of equal length, and sharpened to a slender conical point; they should be well tempered steel, but not tempered to a degree of brittleness; if they break off the instrument is ruined, therefore of no r service, better throw it away and get a perfect one.

There are small sizes of dividers, called "Sprinjg Dividers."* They are very useful but not absolutely necessary for the beginner. Such tools are also called 'Bow Dividers."

There is another form which is known as "Hair Spring Dividers," which have a spring attachment, adjustable by the working of a small set-screw with a milled head, these instruments are of great service to the Mechanical draftsman, but not at all necessarv for the beginner in architectural drawing.

Divider

Compass

Compasses and Dividers are two separate and distinct tools.

•See Figure 15a.

Compass — Every case of instruments should have at least Three Sets of Compasses, including a small spring compass for lead-pencil work and a similar one with a drawing pen for the purpose of inking in circles of very small diameter.*

Bow-Dividor

Kow-rnncil

J^ow-Pcn

The larger compasses, of most use to the beginner, are about 4 inches long, and one about 5j/i or 6 inches long. These are very convenient sizes. It is not necessary that either of these instruments should have more than one steel point, or rather a steel point to more than one leg, but they should each have a pencil leg, and a drawing pen leg, and the larger one should have an extension bar, which is used in conjunction with the other parts for the purpose of making very large circles, i. e., circles with a radius up to 14 inches, beyond that, all circles must be made with a "Beam Compass," but the draftsman will have no use for a beam compass until he has advanced to the making of large (detail) drawings.

The extension is fitted into the stock of the compass, and either pencil or pen leg is inserted in the open end of the extension.

* Point Dividers usually accompany these spring compasses, but they are not necessary for the beginner.

Before beginning work, the larger compasses should be carefully examined and if the steel point* is found to be a long tapering conical one, it must be removed from the socket or holder by releasing the small thumb nut, and the point reversed in the socket, in such manner that the shouldered, sharp needle point, will project the smallest fraction of an inch, beyond the point of the lead, or drawing pen, when either one is in the instrumentf

'Tfae beginner nrtlj knowi about this point, hence the necnnlT of tit, will, be neceiMrr to, make a new adjustment as to the exact lenith

The long conical point first removed, is for use in the making of large drawings, Detail Drawings, and the draftsman will have very little use for it in general practice. This point should never be used for smallscale work. The needle point is the only one to use for small work. If the long conical point is used for small work it will bore a very large hole in the paper, and this is very undesirable.

Some compasses have a short spindel or handle at the top, which is a great convenience in handling but not a necessity.* nG.i8

Beam Sweep— Very large circles, those of a radius of more than 14 inches (28 inches in diameter), are made with a Beam Sweep, or Beam Compass; sometimes a piece of string is used, or a stick with two holes, one at each end, one for a lead pencil, the other for an awl, a sharp needle or large pin. But, and as

'Compasses are also called "Sweeps."

said before, the beginner will have no use for these things, and this information is given here, incidentally. The value of these aids and fuller information concerning them will be found in books on advanced work.

The Ruling Pen or Drawing Pen — ^This is one of the most important tools needed by the beginner. It is the most used instrument, and the one requiring the greatest care and attention.

V ncia

Drttwiog Pen

Curve Pen

A Ruling Pen should be of good steel, well tempered so the "nibs" will constitute a stiff spring, of such degree of hardness that they will not bend at the points when pressed closely together; or, in other words, the points should spring back to a normal position as soon as the pressure is removed.

It is important that these nibs should be of equal length; if they are not of equal length at the start (often they are not), they should be "set," and it may be necessary to grind one or both nibs to bring them to an even length.

The Pen should be handled very carefully and exactly as described under heading of "The Handling of Instruments." If the point of pen cuts in the paper, scratches or makes an imperfect line, it should be set before further using.

When a pen is in proper condition it is capable of producing a very fine line (hair line), or a bold, heavy line at the will of the one handling it.

The Scale — We have now reached, perhaps, the most important of all instruments, so far as the actual needs of the student go.

The Scale,* which for the purpose of a practical description may be designated as a rod of wood with various markings upon its tace or faces, in a certain series; each series representing feet and inches. In the form most used by students it has a triangular cross section, with a cove running its entire length and midway through the face of each of the three sides or planes.

Usually there are four systems of measurements on each face ; two on each edge, one reading from the left to right, arid the other from right to left. Of these two, usually, the smaller scale, reads from the left to right and the scale at the other end of the rod, which is just double in proportion to the first, reads from right to left.

Example — If the scale readmg from left to right is J4 inch to the foot, that reading in the opposite direction will be }i inch to the foot. And this system is

*For fuller information referring to the Scale, see page 56.

uniformally carried out on each edge or each face of the rod of wood.

It should be carefully observed that the figures representing the lesser scale are stamped on the face surface, while the figures representing the larger or greater scale, at the other extremity, are stamped within the cove.

Some students have difficulty in learning to read a scale; consequently it becomes necessary to give a little space for a minute description of it and this will be done in the next chapter under head of "The Handling of Instruments."

Lead Pencils — At least two lead pencils are needed : a soft one, No. 2, for making notes, sketching, making calculations, etc,; a harder pencil. No. 4 or No. 5 (according to the hardness of the surface of the paper upon which the lines are drawn.)

A pencil should be sufficiently hard to produce a clean, sharp line without cutting unduly into the surface of paper. Some draftsmen use a 6, H., or harder pencil, but as a rule, such are too hard for common or general practice. The writer prefers, therefore advovates, the 5, H. or number 5 pencil for general work on small scale. Whereas a 4, H. or No. 4 pencil is admirable for scale drawings ranging from ^'^ to 3'' to the foot (one quarter full size). Beyond this, including detail at full size, a softer pencil, No. 3, or No. 2, will be found much more desirable.

Erasers or Rubber — Just like other people, draftsmen will make mistakes, and it is proper there should be a way provided for their relief. (See Erasing Shield, Fig. 50.) It must not be thought by the student that a provision for overcoming his defects is in any way intended to justify errors. But in the execution of all his work, he should aim at correctness of execution; he should also be just as careful that his work is kept as free from soil as is possible; he should remember that "Cleanliness is next to Godliness" also that "a thing of beauty is a joy forever."

Note Book — The student will find a "loose leaf note book" a valuable acquisition as an aid in recording and keeping notes, formulas, memorandum of technical terms and much data that he should remember or have for future reference.

No student should begin his studies until he has provided himself with a note book; he should keep it by his side at all times during study, make frequent entries; and the teacher should encourage him in so doing by pausing at opportune moments to give directions of information on points to be noted.*

And this completes the list of requirements for the student for the first year course in Architectural Drawing.

•Sec "Note-Book." page 72.

II. The Handling Of Instruments

The T-Square — The function of the T-square is to facilitate the making of straight lines and to make such lines parallel. It is a straight-edge, with a cross piece at one end, the object of which is to insure the lines being straight and parallel. (See T-Square, page 14.)

To use the T-square, lay it flat on drawing board so the blade, full width and length, will be in perfect contact with board. The head of square, out-side of and resting against the left hand edge of board. The thick part of the head, that part which projects below the blade, should be below the top surface of board in such manner that it forms a shoulder or flange bearing against the edge of board, thus :

This facilitates the keeping of T-square in the

*HMfe:

correct position. For the actual practice in making lines parallel to each other, the square is slid up and down along the left edge of board, and keeping the head in perfect contact with the board at all times. To do this it is necessary to rest the left hand on top of blade just where it joins the head; hooking the little finger over the back edge of head and pressing it closely to the board. If the hand is in a correct position, the thumb will drop and rest naturally on drawing board and in contact with the lower edge of blade, close to its juncture with the head. The two middle fingers will rest on the top of blade immediately over the head, and the first finger on the board, impinging on the top edge of blade. In this position the thumb and first finger will span across the blade. This is the correct position and the student should be very particular to see that his hand assumes this nG.2i.

WV'^

J

*

A position, each and every time he desires to handle th^ square for the purpose of making lines of any sort. In this position the hand has perfect control over the T-square, and the head of it is kept in perfect contact with the board as is necessary it should. When, in the course of the work, it becomes necessary to remove the hand from the square, as it frequently does, and it is desired to keep the blade in proper position on the board, it is accomplished by sliding the left hand along the top of the blade in a direction toward the right, at all times maintaining constant pressure on the top of blade to prevent its moving, and the blade is thus held firmly, until the necessary work is done. When the hand is removed from the blade in the last position, it must be returned to the head of square, with the little finger hooking over the back edge, just as first described, and thus insuring a perfect contact ready for a fresh beginning. The movement of sliding the left hand over the blade is repeated every time it is desired to use a set-square in contact with the T-sqtiare.

The Set-Square — ^The function of the set-squares is to facilitate the making of short lines perpendicular or at an angle to lines drawn by the assistance of a T-square, also to make short lines in any direction in conjunction with the T-square or another set-square.

Two set-squares or triangles have been described, and the method of handling obtains to both. In other words, the two set-squares are used in one and the same manner, the only difference being the angularity of the line drawn. It may be found convenient at times (very rarely, however), to use two set-squares conjointly, but as an alternative, in architectural drawing, it is much more convenient to use one set-square and the T-square in combination. The method for doing this, is to place one edge of a set-square parallel to the line to be duplicated, then bringing the T-square blade, with its upper edge resting against that edge of set-square, most conveniently remote from the edge which parallels the line to be drawn; and then, by sliding the set-square along the edge of blade of T-square, any number of lines each parallel to the other may be made.

In this operation, it becomes extremely necessary that both T-square and set-square be held rigidly in place, until all needed lines are drawn.

There are times when it is convenient to use a set-square independent of the T-square for the making of a perpendicular line, but it is the exception, and as a rule, the T-square and set-square should be used as one instrument. Never try to make a perpendicular line with the set-square alone if it is at all possible to use the T-square in conjunction.

The French Curve — The French Curve is a very desirable instrument. Its use as before explained, is to aid in the making of curved lines such as cannot be well made with a compass (sweep) or free-hand. With a proper form of French Curve,* and careful handling of it, a very close approximation to an ellipse can be produced, but in this case, as is the case also with most compound curves, where it becomes necessary to use a number of segments or sections of the French Curve, the change from one segment to another should be so manipulated that the point of intersection, though perhaps a microscopic angle, is reduced to a minimum, if not disguised entirely.

By a dexterous use of the French Curve a clean, sharp line can be made with either lead pencil or rul-

*^|i Isograph Elliptic French Cunre, Fig. 24r ing pen. When the pen is used it is necessary that the flat side of the lower nib shall at all times rest flat against the edge of the French Curve. Fig. 25.

In drawing the line, the pen must be so turned that it will retain this relative position throughout the full length of the curved line. It will be observed that such a line cannot be drawn continuously, with one stroke of the pen but must be made in comparatively short sections; it becomes very important therefore, that the union of one section with another must be

X s very carefully made to insure a continuously smooth line throughout the entire curved line.

French curves cannot be used for all sizes of compound curves. There are many which, because of their size, too small or too large, must be made by hand, a spline or other aids.

To make use of the French Curve it is necessary to first sketch the desired line free-hand with the full combination of curves required, ' that is, by free-hand draw the desired combination curve. Then apply the wooden instrument and discover that part of segment which most closely fits a portion of the line sketched.*

^Scc Fig. 26.

i

The section thus compared should be as large as possible. If a slight checking by pencil mark be now made on the face of the wood curve at the two extremities of the section fitted, the same section of the wooden curve may be placed upon the sketched line a second time and in the same exact position. This will be found a great convenience, especially when it becomes desirable to repeat or duplicate a combination of curves (a compound curve) in more than one position on the drawing. This expedient also facilitates the inking-in of a line covering the pencil line previously made exactly.

Fig. 27 represents the instrument used in making the example. The figures 1, 2, 3 and 4 show the exact part of the French Curve used for each arc or part of the curve. In making the joinings, care must be exercised that the instrument actually over-laps at the joinings to insure a smooth curve and to avoid angular joinings.

The Dividers — The Dividers are instruments with two finely pointed ends of steel.* The special use of this instrument is to make subdivisions of lines and spaces, particularly where it is not practicable to do so by geometric formula. It is useful in the laying out of lines and surfaces flat, making them straight and of equal length to the circumference of a given circle. This is accomplished by "stepping off^f successive spacings of short but equal length, as many times repeated as may be necessary to travel around the circle. The setting of the divider points for this spacing is taken at random, and if it so happens that they do not come out equally at the end, or where the last movement of the points in the revolving

•Sec "Dividers," Fig. 14.

tStepping-ofif is accomplished by holding top of dividers between thumb and index finger and revolving the points from left to right, each point being alternately in contact with the paper, motion falls short or laps over the point from which the first stepping was made;* in such event the distance from the last regular spacing and the point of beginning must be taken separately. A straight line is now drawn at any convenient place on the paper or on a separate paper, and it is laid oflF into the same number of equal parts of same dimension, corresponding with the peripheryf of the circle, then the lesser measurement which was taken as a last movement about the circle, added. If this is carefully done, the