Drafting is a highly specialised skill and a draftsman plays an important role in the design process of any construction project. All engineering or contruction projects start at the drawing board, the key domain of the drafstman. In other words, a draftsman is first and foremost a very skilled artist.
By Lim Chang Shane
Leonardo da Vinci was a famous Renaissance painter, architect, engineer and inventor who designed numerous buildings, machinery and weapons during his lifetime from 1452 to 1519. He was also an excellent draftsman, and if it weren’t for the detailed sketches of his many ideas, they would have remained mere figments of his fertile imagination. Instead, we are left today with pages of visual aids that builders and craftsmen are still able to use to this very day, to gain valuable insight on how their predecessors constructed canals, cranes, carriages and mighty castles many centuries ago.
Draftsmen are skilled artists who draw technical sketches of buildings, machinery and manufactured products. Traditional draftsmen spend hours drawing on drafting tables, using analog tools such as rulers, set-squares and compasses. Nowadays however, most contemporary drafting is done with the help of computers. The most commonly used Computer Assisted Design (CAD) programs in the workplace today are AutoCAD and Solidworks.
Preparation of engineering drawings
The primary responsibility of a draftsman is to transform the hand-drawn designs done by engineers and architects into working drawings on the computer. Before the construction or fabrication phase, the engineer or architect usually sketches his design on paper. By studying these sketches, along with other specifications and supporting documents, the draftsman will then go on to prepare preliminary drawings on the computer. These drawings are meant to provide a visual overview of the project for engineering/architectural review. The draftsman is also expected to draw multiple views of the same subject, such as sectional and isometric views, in order to depict the overall plan.
An experienced draftsman also performs calculations and examines design documents to identify and verify specifications. By collecting and analysing information in consultation with engineers/architects, he helps to resolve discrepancies whenever they occur. In the event of any design changes, he has to modify the drawings and even redraw the entire system if necessary.
Besides making updates and corrections to plans, a draftsman also has to add project-specific notes to the plans and profiles sheets, and sometimes even calculate and compile quantities of the materials required. He also has to arrange the plans in a logical order for ease of retrieval. For instance, grouping drawings of mechanical and electrical installations on a floor-by-floor basis will save an engineer from having to flip through stacks of drawings to look for the specific information he needs.
The greatest challenge a draftsman faces is to develop the necessary concepts that clearly portray the intentions of the design engineer. To do so, a variety and number of criteria must be compiled, calculated, and included in the construction plans.
Bridge between engineers and contrators
A good draftsman is also highly valued in the office because he serves as the bridge between engineers and building contractors.
For instance, during the construction phase of a building, the draftsman will prepare construction plans to inform contractors about the engineering direction of the project. He has to draw a site plan that shows the location of the building on a plot of land. To do so, he has to attend site reviews to acquire information about the site. He will then have to come up with a detailed floor plan, along with measurements, to show contractors the layout of the building. A side elevation drawing will illustrate what the building looks like and contain information on the size, material and design of different parts of the building.
Meanwhile, the specification of materials, layouts of pipe installations and dimensions of floor plans will change constantly, depending on site conditions. The draftsman has to update the shop drawings regularly, because the drawings would soon be riddled with scribbles and corrections, and be rendered virtually illegible otherwise.
Besides being efficient and accurate in producing drawings, a draftsman must also be able to depict the relationship between components and their parts. For example he must be able to show how the various parts of a cabinet are to be fitted together, to calculate dimensions, angles, curvatures and tolerances accurately, and to draw them to scale. All these are essential details that must be communicated to the contractors.
A craftsman with many hats to wear
A draftsman must also be able to maintain tight deadlines. In some offices such as the headquarters of a construction firm, a draftsman will work on multiple projects that are all being developed at the same time. Meeting the deadlines on all of these sites will obviously require a lot of discipline and effective time management from the draftsman, as well as an ability to prioritise his work.
To be proficient at his work, a draftsman must first and foremost be able to interpret engineering and building drawings. He must also be skilled in conventional and automated drafting methods and be familiar with drafting standards, symbols, techniques and equipment. Knowledge of mathematics such as algebra, trigonometry and geometry is also needed to perform engineering calculations such as calculating distances and elevations, and to accurately draw them to scale.
Having said all that, drafting can be a very rewarding career if you have a strong interest in the profession. To go through an entire project life-cycle – from the development of the design, to slogging through countless revisions until the final construction drawing is confirmed, and to finally seeing those plans become a real-life building – is an immensely satisfying experience. There is that indescribable pride in knowing that you have played an important part in the construction of a structure that hundreds, if not thousands, of people will see and use every day.
The career prospects for talented draftsmen are also bright – with experience and an exemplary work record, it is possible for junior draftsmen to advance to senior positions such as a design engineer, a mechanical and electrical coordinator, or an architectural coordinator. These are just a few of the many ‘hats’ that a master draftsman will wear throughout his career, not unlike his multi-talented forebear, Leonardo da Vinci.