Technical drawing

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Geometrical Drawing

Introduction to Technical Drawing and Technical Drawing Equipment

Care and Use of Equipment

Drawing-boards and clips. T squares, set squares, pencils, rulers (metric), erasers, compasses, dividers, radius gauges, protractors, scale rulers (metric), layout of paper, title blocks, lettering, types of lines, plane geometry.

Construction of Geometrical Shapes

Triangles: mention of Pythagoras, quadrilaterals.

Polygons: enlargement and reduction of plane figures and similar plane figures.

Division of lines.

Bisection of lines.

Construction and use of plain and diagonal scales.

Scale: drawing using scales of 1:2; 1:5; 1:10; or 2:1; 5:1, 10:1

Angle construction and bisection

Circles: Center lines, parts of a circle (segment, sectors, chords, tangents and normal). Circles in contact and compound curves (drawing of shapes involving compound curves); ellipse and its properties. Loci. Parabola, hyperbola, the sliding ladder, Archimedean spiral, cycloidal curves, involute curve, helices and link mechanisms.

Solid Geometry

Lines in space (orthographic projection of lines inclined to one or both reference planes), identification of solids (prisms, pyramids, cones, cylinders, spheres). Solids in orthographic (First Angle and Third Angle); development of geometrical solids including developments of cut length of inclined edges. Section so f geometrical solids - conic section s(circle, parabola, hyperbola, and ellipse).

True shapes of cut geometrical solids.

Auxiliary views.

Isometric and oblique drawing (without the use of isometric scale).


Mechanical Drawing

Sketch Drawing

Sketching of simple and compound solids using isometric, oblique, perspective and orthographic projections. Use of isometric grid paper and squared paper.

Mechanical Drawing

Orthographic projection: either First or Third Angle projection including sectional views of machine and engine components, together with simple assemblies incorporating bolts, nuts, studs and screws. Preparation of working drawings from free-hand sketches and models. Dimensioning part lists, title block data, free-hand sketching in both orthographic and pictorial form, from sketches of simple engineering components; conventional representation of bolt heads, nuts, screws, and rivets. Keys cotters, simple riveted joints. Locking devices for screwed fastenings. Descriptions of screwed fastenings. Descriptions of screw threads and their particular uses. Recommendations of B.S 308 (1972), including limits and tolerances, to be adopted.

Building Drawing

Sketch Drawing

Free-hand sketches of building plans including Site plans. The architect's scale. Practice in sketching from pictorial projections. Preliminary sketches. Material symbols.

Building Drawing

Orthographic projection First Angle or Third Angle including layout of different types of roof trussing, including details of joints and wall fastenings.

Floor plans and symbols.

Several single and two-story floor plans include all doors and stairways.

Foundation detail.

Detail drawing of foundation plan symbols and construction detail.

Symbols on architectural drawing to locate doors and windows. Pictorial projections without sections. Section detail foundation of standard domestic building include solid structure and stabilizing materials.

Section detail walls. Details of standard wall structure include damp-proof course reinforcement (detail of main and partition wall).

Section detail floor. Detail of concrete floors. Wooden floors on the ground and suspended (reinforced concrete floors), simple description of top finish.

Wall opening. Detail of lintels of wood and concrete flat arch include trough.

Section detail of windows. Detail of section of timber frames include standard type casement only. Metal window frames. The window frame should include fixing frame and wall section.

Doors. External door frames and wall detail include methods of fixing roofs and roof drainage.