Creating A Technical Drawing
Technical drawing, although also used to product design, architectural studies or engineering is also used in film and theatre. The purpose of a technical drawing in film or theatre is to communicate clear dimensions and space of a designated room or set proposal. Using examples from my current unit project: Transforming Location, I will demonstrate how to transfer visual room features into a technically comprehensible drawing that will then be used to create a 1:25 white card model.
Continuing from the survey sketch with accurate measurements, you will not be able to replicate the real, life sized measurements onto standard tracing paper. The tracing paper used in technical drawing in A1 size. This allows you to present your work in landscape when used in conjunction with a drawing board which is also A1 size. Often, draftsmen will scale down these measurements. In this instance, I will work in a 1:25 scale as this is what my project brief requires.
The first step is to produce a preliminary drawing onto standard, A4 tracing paper. This must be entirely accurate as you will position this behind the A1 tracing paper. The reason for this is simple: It allows you to prepare the position of your drawings so that the final product will be clear, easy to follow and presentable to the viewer.
To scale down your measurements, simply divide them by the amount you wish to work in. I want to work in 1:25, so I will divide any measurements I have by 25 to get the result.
There are a number of factors to consider when producing your drawing. The first being line work.
There is certain etiquette to the line work seen in technical drawing, the lines have varying thickness and are sometimes dashed. This is because there is often a lot of information to take in, and varying line thickness establishes a certain hierarchy that the eye can naturally follow. The lines also communicate depth and clarity to a drawing, which tells the viewer this is actually a 3 Dimensional space that has been converted to a 2 Dimensional drawing. Another reason is that when the drawing is photocopied, the lighter line work is actually erased due to the brightness of the scan. Draftsmen use this to their advantage however, as they will tend to produce a preliminary of the preliminary in a lighter pencil, allowing for error before committing to a final heavier mark.
Thick, heavyweight lines are created using a 2H pencil. Typically, the thicker the line, the more foreword and important the detail it marks.
Medium weight lines are used for other features, such as beading. This is also used for Titles and Elevation Labels.
Extremely light lines are used to show something is further away or is relatively unimportant.
The finest lines are used to produce general workings out. An example would be to work out a right angle using the 345 method, which I will explain further on. Working out lines look untidy, and so are created in a fine line to be deliberately erased and as we all know, the lighter the line – the easier this is to do.
Dashed lines are used to show an “invisible” or hidden area of an object or room. An example would be a built in wardrobe. In my technical drawing I have used a dashed line to show the direction of elevation indications, because I did not want the viewer to consider these an actual line and because there were no hidden features to my chosen location (so as not to confuse the viewer).
I met up with a family friend, Steve Eastgate who worked as a draftsman for the best part of twenty years and he was extremely kind to show me a few tips into creating a technical drawing. The first being the 345 method:
The 345 method is used when you do not have a protractor or your protractor is too bulky for intricate details but you wish to create an accurate right angle.
The first step is to mark a straight line using a T square.
The second, to make a mark on this straight line from the left measuring 4cms. I find a compass works best as the arc it creates gives you a clear idea of where the preceding marks should sit.
From this new mark, adjust your compass to 5 cms and create a second arc roughly 90 degrees from the left starting point of your straight line.
From the left of your straight line, measure out 3cms to your last created arc and this new point will mark out where you need to place your ruler in order to create a sharp, straight accurate right angle.
Whilst chatting with Steve, he suggested a handy tip to create equal pressured marks. He recommended constantly twisting the pencil on point along the ruler. This keeps the pencil sharper, the line crisper and reduces the risk of producing uneven “wavy” lines. I have used this method and I can confirm that it works!