RACA Journal January 2026 RACA_January_2026 | Page 7

NETWORKING

THE EVOLUTION OF CAD / CAM FROM CAVE WALLS TO CLOUD REPOSITORIES

Associations associations

By Eamonn Ryan

The September SAIRAC TechTalk, presented by Robert Fox, costing estimator at Club Refrigeration, traced the long and fascinating history of technical drawing – from humanity’ s earliest sketches to today’ s digitally integrated design-to-manufacturing environments.

With more than three decades of experience in heat load calculations, equipment selection and technical drawings, Fox offered insights into how Computer-Aided Design( CAD) and Computer-Aided Manufacturing( CAM) have transformed engineering, construction and manufacturing.

A BRIEF HISTORY OF TECHNICAL DRAWINGS The story of drafting begins long before the modern era. Humanity’ s first‘ technical drawings’ were crude but effective symbols daubed on cave walls representing tools, structures and ideas. Ancient Egyptians refined the practice with sketches on papyrus, while the people of Mesopotamian, the Sumerians, recorded designs on clay tablets.

The Greeks gave drafting its first mathematical foundation. Euclid’ s principles of geometry, coupled with simple instruments such as rulers and compasses, allowed more precise design work. The Romans built on this by producing diagrams of aqueducts, roads and amphitheatres – structures that still stand as testimony to their engineering skill.

During the Middle Ages, drawings were largely preserved in monasteries, but the Renaissance reawakened the discipline. Leonardo da Vinci’ s notebooks epitomised the union of art and science, filled with intricate mechanical sketches centuries ahead of their time.

By the 18th century, mathematician Gaspard Monge’ s development of descriptive geometry provided the systematic foundation for modern drafting. With the Industrial Revolution, drawings became indispensable in large-scale manufacturing. New tools such as drafting tables, protractors and compasses enabled precision, while the World Wars accelerated the demand for complex, standardised documentation in industries such as shipbuilding, aerospace and weapons development.

As drawings became central to industrial output, the need for consistency emerged. The establishment of organisations such as the International Organisation for Standardisation( ISO) and the American Society of Mechanical Engineers( ASME) brought about a common‘ language’ of lines, symbols and conventions. Title blocks, placement rules and symbol libraries became standard features of drafting offices worldwide. By the mid-20th century, large teams of drafters filled drawing offices, painstakingly producing plans by hand. Mistakes meant tedious erasures and redraws, underscoring the limitations of manual methods.

CAD ' S ARRIVAL The 1960s ushered in a revolution: Computer- Aided Design. Replacing pencils and paper with digital precision, CAD eliminated much of the inefficiency of hand drafting. It enabled multiple layers, instant edits and highly accurate calculations. Most importantly, it laid the foundation for collaboration – allowing architects, engineers and manufacturers to work within a shared digital environment.

South Africa was not left behind. Early home-grown packages such as Caddy and TurboCAD emerged locally before being acquired and absorbed into international markets. The global tide was unstoppable: by the 1980s, Autodesk’ s AutoCAD had become the industry’ s dominant platform, a position it still holds today. Today, the CAD landscape offers both proprietary and open-source solutions. Proprietary systems, such as AutoCAD, Revit, SolidWorks and Catia, dominate industries because of their advanced features, technical support and seamless interoperability. Competing packages such as BricsCAD offer modular flexibility, while ArchiCAD is widely used by architects for intuitive 3D modelling.

Open-source alternatives such as FreeCAD exist, but their biggest challenge lies in interoperability. Proprietary platforms tend to support the most widely used file types, particularly DWG, while open-source tools often lag behind, restricted to legacy formats such as DXF. This can create bottlenecks in collaboration, particularly when working with clients or partners who expect seamless integration.

Robert Fox, costing estimator at Club Refrigeration.

© RACA Journal

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