The Vocational Aspect of Secondary and Further
Education
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The technical drawing lesson
T.R. Brown
To cite this article: T.R. Brown (1950) The technical drawing lesson, The Vocational Aspect of
Secondary and Further Education, 2:5, 139-145, DOI: 10.1080/03057875080000161
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Published online: 30 Jul 2007.
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THE TECHNICAL DRAWING LESSON
By T. R. B R O W N
Senior Lecturer, Bolton Training College
Principles
~XAMmATmN of the content of any preliminary technical course or of the
curriculum of any secondary technical school reveals almost complete
unanimity in the range of basic class-room subjects. Naturally the secondary
technical school provides a much wider curriculum than does the technical
college in a preliminary course since its students are in full-time attendance and
are completing their full-time education, but the basic subjects remain the
same:--mathematics, science, English and technical drawing. In this article
it is proposed to examine the presence of the fourth member of the groutv-drawing, to discuss the aims implicit in its teaching, and to draw certain conclusions as to class-room technique in the light of these aims.
The practical man finds that he needs to draw rather than to write in the
course of his everyday occupation. This is in no way a criticism of him or his
talents, for the very nature of his work demands a drawing if an accurate and
unambiguous interpretation is to be forthcoming. Words are not his prime
vehicle of expression, but rather an aid to the visual representation. Thus
the drawing is to the practical man, whatever his trade or profession, what
the mathematical process is to the research worker. It is the language of the
engineer, the builder and others of similar callings as algebra is the language
of the mathematician. Viewed in this light there can be no doubt as to its
educational value; the wonder is that it fails to gain an equal place in the
curricula of all post-primary schools, irrespective of type.
The drawing teacher be it technical drawing, practical drawing, or simply
drawing that he teachesmis faced with the task of dealing effectively with the
fourth 'R', and so needs to consider his responsibilities most carefully. On him
falls the task of building up a body of new concepts within the minds of his
students, of initiating them into a new form of thinking and expression, embellished with the various conventions which must be accepted and used if
ambiguity is to be avoided and clarity achieved. He is faced with teaching a
subject which obeys rules as strict as any applying to English grammar. This
being so it is sensible and satisfying to find that all elementary courses in
drawing, whatever their later vocational bias, have in general a common core
of fundamental itemsmthe 'grammar' of the language--which the student must
know and understand before he proceeds to apply this new 'language' to certain
specialised fields.
This analogy between drawing and language can be pressed still further from
a psychological point of view. It is now recognised that every individual
14o
Th8 Technical Drawing Lesson
possesses verbal ability to a greater or lesser degree, just as everyone is endowed
with intelligence, which also varies in quality and in measurable a m o u n t from
person to person. It is reasonable to ask if there exists an analogous factor
which is linked with the mental manipulation of shapes and solids, an ability
to create the three-dimensional whole from the two-dimensional parts, and vice
versa. I f such a factor exists it is a feature of technical drawing. Considerable
research has already been carried out to establish whether or not there is such
a spatial factor. E1 Koussy, x Earle and Milner, 2 McFarlane s and others have
found strong evidence for such a space factor through investigations of practical
ability by performance tests. These tests do not require the use of words a n d - with limitations--are suitable for indicating aptitude for practical or technical
work. T h e immediate factor involved in such testing appears to be linked with
the capacity for appreciating relations in space, and has been named 'practical
ability'. In the light of all the research on this topic now available Burt 4 suggests that this factor of practical ability is m a d e up of two sub-factors, a 'spatial'
factor and a 'mechanical' factor. T h e former is 'concerned essentially with the
ability to perceive, interpret or mentally rearrange objects as spatially related'. 5
This phrase alone must cause any teacher of drawing to ponder on its closeness
to his work. Even more interesting are the further suggestions made that when
relationships between items are viewed statically, correct perception depends
on the facility of the observer to appreciate relationships through movement or
imagined movement of his own organs, or the object observed, or both. It will
be of interest to the reader to endeavour to decide how closely this fits in with
his own experiences when making a drawing in orthographic projection o f a
detail presented pictorially, or vice versa. In the first case he will discover that
he either moves his eyes round to a position which permits him to view front
elevation, end elevation or plan, or alternatively that he rotates the object in
such a way as to present him with the particular view in which he is interested,
while in the second case considerable eye movement will be necessary to link
the three two-dimensional views into the one pictorial view. Pursuing his
argument Burt 6 further suggests that there are two aspects of static relations to
be considered, the one involving two dimensions, the other three dimensions.
This is of the utmost importance in technical drawing, which calls for both these
functions, and would indicate that the teacher's work, and the form of his
exercises should be such as will develop both functions, particularly the latter.
More will be said on this later when the 'spatial' problem is considered. Finally
reference must be made to a piece of work carried out by Macfarlane Smith 7
which showed significant agreement between spatial ability, as measured by a
spatial test, and the work carried out by pupils in art, practical geometry,
engineering drawing and drawing.
T h e r e is but one conclusion to be reached from these findings, that success
in technical drawing is concerned primarily with the development of the
spatial factor. T h e methods of the teacher must be such as will foster this
development to the m a x i m u m in each student.
T.
R.
BROWN
I4x
Aims
In the few published references that are available it is notable that the substance of the previous paragraph is tacitly accepted, and the aims stated
accordingly. Thus in the Preparatory Senior Technical Course Handbook of the
Union of Lancashire and Cheshire Institutes s Practical Drawing is referred to
as follows :--'Drawing, in the Preparatory Senior Technical Course, serves three
purposes--(i) the students acquire a knowledge of the more important
geometrical facts and relations; (ii) they obtain some facility in the use of
instruments and the commoner constructions of plane geometry; and (iii) they
learn how to represent a solid object on a flat surface.' The same Institutes, speaking of
their Senior Course in Mechanical Engineering, place the whole emphasis on a
restatement of the third aim above:--'The main object of this course is to train
students to visualise engineering details from a drawing consisting of two or
more views arranged in orthographic projection.' In a further published
reference Currie, 1° in discussing engineering drawing, says:--'In the course of
his training in engineering drawing the student should gain and d e v e l o p . . , the
ability to think in three dimensions.'
This then is the main aim in teaching technical drawing, but it seems desirable
to determine also what subsidiary aims are involved, since these may prove
valuable in their indications of teaching technique. First comes the recognition
that technical drawing demands a definite motor skill, the ability to use a pencil
effectively and to manipulate the instruments of the drawing board with
dexterity. Just as a child must be trained to hold and use a pen correctly so
must the student be given instruction by the teacher to promote the handling of
his instruments with ease and fluency.
It is a matter of common experience that in a class composed of pupils of
varied backgrounds and achievements those who make most progress in their
drawing work possess a sound background in the elements of plane and solid
geometry. The conclusion to be drawn from this is inescapable, that success in
technical drawing depends in no small measure on geometrical knowledge,
though the achievement of the aim implicit in this statement is far more difficult
than is its recognition. Maintaining the interest of those pupils who have a
good grounding in the subject is often a major problem for the teacher when
perforce he has to teach the elements to those students whose knowledge of
geometry is weak or non-existent. This applies in particular to part-time day
and evening classes.
Finally it must be recognised that technical drawing demands a thorough
appreciation of the facts and conventions, the practices and usages, which give
to it the individuality and the power that the symbol gives to algebra. The
student must be made to appreciate the need for such conventions, to know them
as well as he knows the multiplication table, and through his own work, to
learn to use them properly.
Restating the substance of the previous paragraphs more concisely, the aims
x42
The Technical Drawing Lesson
governing the efforts of the teacher in the early stages of technical drawing
may be said to b e : Principal aim
To lead the students to think in terms of three dimensions so that eventually
they can read a drawing as easily and with as much understanding as they
can read a page of print.
Subsidiary aims
(i) To give the students training in the use of drawing instruments, and
incidentally to foster habits of neatness and accuracy, with skill in
execution.
(ii) To provide each student with a sound background of plane and solid
geometry.
(iii) To teach the rules and conventions governing the detailed representation of a solid object on paper.
In drawing courses of a more advanced nature than those considered here,
where the subject becomes more narrowly vocational, the three subsidiary aims
will gradually yield, to be replaced by a second major aim, that of presenting
specialist information with both verbal and spatial implications. This information the student will be able to interpret, appreciate and apply to the degree to
which he has benefited from the early general teaching of drawing, and his
success will depend on the extent to which the four aims outlined above have
been achieved by his teacher.
Method: (I) Sequence
To the casual investigator technical drawing and algebra appear to possess
little in common, but a closer examination of the scope of each subject reveals
significant similarities. In each, two main aspects can be detected: (a) manipulation and (b) problem solving. In algebra, under the heading 'manipulation',
can be grouped all those techniques which the student uses in solving a problem,
as distinct from his recognition of the line of attack he must follow; in drawing
under this same heading would appear all those geometrical facts and construetions of plane and solid geometry which permit the pupil to solve a 'spatial'
problem. In addition, certain rigorous conventions apply to each subject which
must be accepted and scrupulously observed by the student. It is not unreasonable then to suspect the existence of a certain similarity in teaching method, and
an examination of current trends in the teaching of algebra may prove of some
value to the teacher of drawing.
At the beginning of the present century algebra was generally taught through
the medium of manipulation and it was only towards the end of a course that
the student had an opportunity of applying these ancillary techniques to their
true purpose, that of solving problems. Often the student found the step too great
for his abilities, and had to rely on manipulative skill alone for any success that
might be his in an examination. In other words the reasoning ability required
T.
R.
BROWN
x43
for solving a problem was given little or no chance to develop, and for many
students algebra tended to become meaningless manipulation. In recent years
the picture has changed. It is now recognised that mathematical ability, in
common with other abilities, must be carefully nourished, and given opportunity for gradual development through correct teaching methods. To-day
algebra is taught through the problem, and any analytical and reasoning ability
that the students may have is exercised, gradually, from the first. Manipulation
now falls into its proper place as an agent in the solution of problems, and its
various aspects are considered as and when the need arises, thus making it
meaningful to students.
Treating the teaching of technical drawing on similar lines raises some
interesting points and throws a light on the sequence to be followed in technical
drawing. Since in this case the prime aim is to develop the student's capacity
for spatial thinking every exercise he carries out on the drawing board or in
the sketch book must present a challenge to be accepted, a problem to be solved.
There must always be active thinking. And there must be a demand for
mental visualisation if the student's powers of spatial perception are to be
quickened and strengthened. All too frequently the joy that students experience
in drawing lies in the finished product--as a mere portrayal--rather than in
having dominated a problem by the application of real thought. The average,
or below average, student tends to like drawing because too often little real
thinking is required yet there is something tangible, or even complicated, to
show for his efforts. This is in sharp comparison to the feeling that possesses
the student when asked to do an English exercise or solve an algebraic problem
where the finished product is but a few lines of writing or of symbols and figures.
Here satisfaction comes in the mental effort that has been brought to bear on
the topic.
The second point of resemblance between technical drawing and algebra
relates to the manipulative side of the subject. In this can be included all
facts and constructions of a geometrical nature which are so often taught in
isolation, and are such a source of annoyance to students who cannot see their
usefulness and future application. Here the moral is plain to see, and if all such
work is integrated within the teacher's main approach so that students realise how
necessary are these geometrical facts and constructions in furthering their own
attempts at solving problems through drawing, then interest will be stimulated
and objections will disappear. How is the teacher to do this? By commencing
the drawing course with a study of the principles of orthographic projection
and making all else ancillary to this theme throughout the course. In the past
there has been a reluctance on the part of teachers of drawing to begin in this
way, possibly owing to a feeling that progress could not be made without a
thorough grounding in geometrical principles. In the experience of the writer
this is not so. Thus geometrical work should enter the course as the need for
it arises. Careful arrang&ment and grading of exercises will be called for so
that some continuity and order can be preserved in the appearance of this
I44
The Technical Drawing Lesson
fundamental 'tool' of drawing, but such time as is expended in planning on these
lines will be time well-spent in terms of teaching success.
Under such a scheme the conventional aspects of drawing-office practice
would feature from the beginning, and so the student would have a correspondingly longer period in which to absorb them and make them part of himself
than he has at present, when after a laborious apprenticeship to geometry he is
eventually introduced to them through orthographic projection.
There remains one final item which is tacitly assumed in algebra but which
requires separate consideration in drawing--skill in the manipulation and use of
pencil and instruments. The teacher must not neglect to foster this, nor must
he accord it undue prominence, and he should himself demonstrate to small
groups from time to time, and particularly early in the course, the correct use
of the various instruments, tee-square, set squares, compasses, pencil. He must
also check immediately any wrong and time-wasting habits he may see students
using during his supervision. By this means the motor skill will be promoted and
speed, accuracy and neatness will result.
Method: (2) The 'Spatial' Problem
Much has been said about this problem and its importance. It will generally
assume one of two forms, (a) an exercise which will require the student to make
a drawing in orthographic projection from certain data, or conversely (b) an
exercise in which the student has to produce a pictorial view, or sketch of a solid,
of which he is given certain views arranged in orthographic projection. In (a)
the mental process is essentially one of analysis, the student breaking down the
presentation of the object into a number of two-dimensional views which he
develops in their conventional placing on the drawing paper. In (b) however
the mental process is reversed, and here the student is called upon to integrate
the views into a three-dimensional form. The latter involves the true essence of
spatial thinking, and of the two types of exercise is the more difficult for the
student. Yet it represents the supreme aim of the teacher in that it reproduces
the reactions of the trained practical man when he studies a working drawing.
One of the difficulties facing the drawing teacher is curtailing the percentage
of relatively useless copying which his presentation of data so often includes.
This difficulty tends to diminish if problems are restricted to forms (a) and (b)
above. Exercises which involve the addition of a third view to two given views
should generally be avoided since too much of the student's time is given to
the motor skill of using his drawing instruments effectively, and too little time
devoted to spatial thinking. This same reasoning applies to all exercises which
involve a considerable amount of copying.
There are four main ways of presenting the details of exercises in analysis(i) through a free-hand dimensioned sketch, made by the student, of the actual
object or a model of it; (ii) through the actual object or model; (iii) through a
pictorial view; (iv) by verbal description. O f these fofir methods (i) and (ii) are
particularly useful in the early stages of teaching orthographic projection in that
T.
R.
~ROWN
I45
they both permit easy visual movement from the solid object to the fiat surface; (iii)
has a wide application over the whole course and is particularly important since
it approximates to the practical situation in the workshop; (iv.) can be used when
the exercise is fairly straightforward, free from ambiguity and complicated
detail. O f these four methods (i), (ii) and (iv) offer no difficulties in their presentation, and duplicated sheets are most serviceable for exercises of type (iii).
Where integration is involved the student must study the views in orthographic
projection, and this again is best accomplished by the use of duplicated sheets.
Method: (3) Class-room Technique
One final aspect that requires consideration is that of the distribution of initiative between teacher and taught. What part of the time should the teacher spend
in exposition and what time should the students spend at the drawing board? No
exact answer can be forthcoming, but if the teacher provides him_sell'with a clear
aim for every drawing lesson he will most certainly discover that some part &
each lesson will have to be centred on oral and blackboard work. Some problem, and any geometrical implications of it will have to be considered in each
lesson. The essence of the teacher's work should be in guiding the students by
skilful question and argument to arrive at a solution to this problem. He should
then test their powers of application and practise their spatial sense by letting
them work individually at an exercise similar in form but different in content.
The effect of absorbing the geometrical work within the main framework of
orthographic projection will be to distribute more evenly the amount of oral
teaching over the whole course, instead of crowding it into the earlier stages as
at present, when geometrical work precedes orthographic projection.
Finally, throughout the whole of the work in drawing the teacher should
develop and foster student initiative. At all times he should encourage his
students to reason out things for themselves, to 'see' for themselves. By so doing
will come that true understanding which will permit the student to apply the
knowledge he has gained, both sensibly and effectively, to the more advanced
branches of the subject.
REFERENCES
x. EL KOUSSY, A.H. ( 1935)- 'The Visual Perception of Space.' B..7. Psy., Monograph Supflement, No. 2o. London.
3. EARLE, F. M. and MILNER, M. (x929). The Use of Performance Tests of Intelligence in
Vocational Guidance. London: H.M.S.O.
3- McFARLANE, M. (x925). 'A Study of Practical Ability.' B.~. Psy., Monograph Supplement,
No. 8. London.
4. BURT, Sir CYRIL (t949). 'The Structure of the Mind.' B.oT. Ed. Psy., Vol. XIX, Part 3,
pp. I76-I99. London.
5. Ibid., p. t88.
6. Ibid., pp. I88--x89.
7- MACFARLANE SMITH, I. (x948). 'Measuring Spatial Ability in School Pupils.' Oct.
Psy., Vol. XXII, No. 3, PP. t5o-x59 . London.
8.
(I949)- PreparatorySenior Technical Course--Schemes and Syllabuses (Part A, x948-t95o),
p. 78. Manchester: Union of Lancashire and Cheshire Institutes.
9.
(I949). Engineering Courses--Schemes and Syllabuses (Part B, I~9-'I95o), p. 89. Manchester: Union of Lancashire and Cheshire Institutes.
lo. PARKINSON, A. C. (z946). A First Sear Engineering Drawing. Foreword by J. H. Currie,
p.v. London: Pitman.
K