Digital class 6. Drawing and cut

Drawing and cut

Introduction

Hello! Welcome to the sixth session of Selected Design Topics II. In the previous three sessions we have looked at three two-dimensional representation techniques and how to show our work. In this class we will focus on volumetric representations, specifically on two topics related to them: the drawing and cut of a model.

First, we will consider what a volumetric representation is for and examine one of its most notorious forms: scale models, and also a way to classify them. We will learn which are the ideal materials and which ones we should avoid to achieve professional results when making a model.

Then, when it comes to the drawing of the scale model, we will identify some of the essential tools. We will study the scale as one of the most important concepts to draw a model and we will analyze a taxonomy that divides the scales into three types. We will explore the factors that go into choosing a scale and we will study the procedure for making a scale model, both using an architect’s scale and without using it. We will also look at some useful considerations for drawing a scale model.

Finally, we will tackle our second topic, the cut. We will point out some of the most used materials. We will identify the two most important types of cuts that can be made while cutting a model. We will discover some recommendations for cutting while making a model and, finally, we will talk about a very particular type of cut that will allow us to create curved volumes or textures in a scale model.

We wish you every success in this sixth session in which you will be able to acquire tools that will be very useful for you to communicate efficiently through a three-dimensional model. Let us get started.

Content developement

A volumetric representation allows us to create an imaginary or real object in three dimensions to convey a message to the observer. Among the different forms of volumetric representation, the scale models stand out, which are prototypes of an object, machine, piece of furniture or building. In disciplines such as architecture, according to their level of detail, scale models can be volumetric and detailed. A volumetric model allows you to see only the exterior of a building, while a detailed model also shows its interior.

To make a model we must consider the use of certain materials and tools. In terms of materials, we suggest medium illustration paper (it can be found in three thicknesses: thin, medium, and thick), which offers the rigidity that Is needed to make a model and a finish that can be painted professionally. It is also possible to use acrylic sheets to represent glass elements. On the other hand, to get professional results, it is advisable to avoid certain materials such as craft foam, cellophane, kite paper, craft paper, as well as commercial accessories (for example, plastic furniture or transport).

Pencils are essential tools to draw a scale model, we suggest a soft pencil (2B); a gum eraser; an architect’s scale, (it is a special rule that usually has 3 faces, in each of which two scales are indicated) preferably metallic so that it resists in case it falls off the drawing table, and It should have the following scales: 1:20, 1:25, 1:50, 1: 75, 1: 100 and 1: 125; a steel ruler, to make cuts using a X-Acto knife without damaging It; a set square (preferably graduated), to ensure that the pieces that have right angles are effectively 90º; some stencils of ellipses and circles, beveled so you can  draw with ink in other projects; a compass, preferably metallic and with an extension to make larger circles; and a protector.

Drawing

To draw a scale model the most important thing to consider is the scale on which it will be built. A scale is the relationship between the dimensions of the drawing and the actual dimensions.

1. The natural scale, in which the dimensions of the representation and the dimensions of the real object are equal, and it is expressed as 1: 1, which means that 1 centimeter of the drawing or model is equivalent to 1 real centimeter.
2. The reduction scale, in which the dimensions of the representation are smaller than the dimensions of the real object, for example:1:50 means that one centimeter of the drawing or model is equivalent to 50 real centimeters.
3. The magnification scale, in which the dimensions of the representation are greater than the dimensions of the real object, for example: 2: 1 means that two centimeters of the drawing or model are equivalent to 1 real centimeter.

The scale choice depends on the discipline to which the creator belongs. An architect, for example, usually makes scale models in scales between 1:50 and 1: 200. Another consideration for choosing a model scale are details. If It Is too difficult to make little details, the size of the model should be larger.

The procedure to make the drawing or model of an object at a certain scale is:

1. Measure the real object and write down all its measurements in centimeters in a sketch.
2. Take the architect’s scale and find the scale at which the drawing or model will be made. (Example: 1:50). That side of the architect’s scale is the one we will use throughout this procedure.
3. Choose a measurement that you want to transform to a certain scale. (Example: 90cm)
4. Draw 90cm on the side of the architect’s scale that you identified in step 2.

If the scale you want to work on is not on the architect’s scale, you can easily scale your model by following the next steps:

If you want to draw a 1:10 scale drawing or model, how long (In centimeters) should the side of an object that measures 120 cms in reality measure in the representation?

1 drawing cm : 10 real cm

How many of drawing cms? : 120 real cm

Answer: (120 x 1) / 10 = 12 cms.

Some important considerations for drawing are.

1. Avoid applying a lot of pressure with the pencil on the paper because the marks that are made will have to be erased.
2. Use the square to make sure the right angles are 90º.
3. Use the architect’s scale only to measure, never to draw or cut.
4. Use the same line for all the elements that have the same dimension, this will optimize our time and will help the measurements of the mentioned elements to be identical.

Cut

Some of the basic tools to cut a model are a X-Acto knife, with the same features as the one we used in our collage session; a circle X-Acto knife (if the model requires it); a cutting mat, with the same characteristics as the one we used before; and a nail file.

There are two types of cuts:

• 90 degrees cut (BATERIA: Maqueta Básica, Parte 1). It Is perpendicular to the paper surface. To form a corner, the thickness of an illustration paper piece must be glued to the surface of another illustration paper piece, according to the following scheme, in which the edge of two illustration paper pieces cut at 90º is shown:

• 45 degrees cut. It must be made at 45º from the paper surface. To form a corner, the thickness of one illustration paper piece will be glued to the thickness of another piece. This type of cut requires more practice. The following diagram shows the edge of two illustration paper pieces cut at 45º:

Some recommendations for cutting are

1. Cut the straight lines with the support of the steel ruler.
2. Do not expect the X-Acto knife to cut the illustration paper in a single pass. Several passes must be made.
3. Consider the thickness of the material and subtract it from the dimensions of a certain element of the model if necessary.
4. When you want to subtract a part from an illustration paper element, you should not cut that part from end to end, but from one end towards the center and then from the other end towards the center. This will prevent us from damaging the corners of the element from which we are removing a part.
5. Use the nail file to smooth or remove excess paper.

There is a special type of cut called a die. It is a cut that partially sections the paper, without completely going through it with the X-Acto knife. The dies can have two goals:

1. Helping the paper to be curved and thus form the surface, for example, of a cylinder.
2. Give the paper a different finish than smooth. This makes it possible to represent, for example, floor.

Study the scale and cut of a model in the next videos:

• Have you ever Imagined to be a smaller or a bigger size than you actually are to be able to visit a totally different surrounding? Where would you like to go?
• How can models help people? Is It Important for them to be accurate?
• What Information about drawing and cutting scale models was new for you?

Considering the technique that we have learned to draw and cut a scale model, do the next assignment.

Conclusion

Now that we have finished studying some of the most important notions about volumetric representations (drawing and cut), let us review the content of this session.

First, we learned that a volumetric representation allows us to create an imaginary or real object in three dimensions to convey a message to the observer. We pointed out that scale models are one of these representations, which can be classified into volumetric or detail models. Also, we considered that to get professional results, a model must be made by using materials such as illustration paper and avoiding others like craft foam.

We examined some of the tools that are needed to draw a model, such as scale. We studied scale as the most important concept to build a model, which is the relationship that exists between the dimensions of a drawing and the actual dimensions. In addition, we learned that there are three types of scales: the natural, the reduction and the enlargement scales, as well as the way to express each one. We explored the factors on which the scale choice depends, such as considering the discipline to which the creator belongs and we studied the procedure to make a scale model, which begins by measuring the real object, and ends with the scale drawing of all the parts that make up that object. We also looked at some considerations for drawing a scale model, like not applying too much pressure on the paper with the pencil.

Regarding the cutting of a model, we pointed out some of the most used materials, such as the X-Acto knife. We were able to identify that there are two types of cuts: 90º and 45º, which we described in text and through a scheme.

We discussed some suggestions for cutting, for example, using the steel ruler to section straight lines. Finally, we learned that there is a type of cut called die that consists of marking the paper without separating it to create curved volumes or generate textures.

As a viewer, it Is Important to know how to scale an object because, It allows us to understand how diverse objects can be represented In a size different than the actual one. We are now able to notice mistakes, to remark when the elements that compose a model have not been scaled using the same criteria. As creators, knowing the procedure to scale an object Is essential to draw and cut a model correctly. 

Congratulations on completing this sixth session of Selected Design Topics II! Keep going! Do not miss our next session in which we will learn how to join the pieces that you have drawn and cut.

Information sources

Scale Models and Scale Drawings

How to Cut | Architecture Modelmaking 101

10.- Escalas de representación

BATERIA: Maqueta Básica, Parte 1

BATERIA: Maqueta Básica, Parte 2