CHAPTER 5 Sketching Applications

Transcription

1 CHAPTER 5 Sketching Applications I N T R O D U C T I O N Sketching, or freehand drawing, is drawing without the aid of drafting equipment. Sketching is convenient because only paper, pencil, and an eraser are needed. There are a number of advantages to freehand sketching. Sketching is fast, visual communication. The ability to make an accurate sketch quickly can often be an asset when communicating with people at work or at home. Especially for technical concepts, a sketch can be the best form of communication. Most drafters prepare a preliminary sketch to help organize thoughts and minimize errors on the final drawing. The computer-aided drafter usually prepares a sketch on graph paper to help establish the coordinates for drawing objects or just to organize the drawing before beginning. Some architects, designers, and drafters use sketches to help record the stages of progress until a final design is ready for formal drawings. SKETCHING TOOLS AND MATERIALS The pencil used for sketching should have a soft lead. A common No. 2 pencil works fine for most people. A mechanical pencil with a soft lead such as H, F, or HB is good. An automatic 0.7-mm or 0.9-mm pencil with F or HB lead is also good, and commonly used because of its availability and ease of use. Soft pencil leads allow for maximum control and variation of line weight. The pencil lead should not be sharp. A slightly rounded pencil point is best because it is easy to control and does not break easily. The lead point is not a factor when using an automatic pencil. Different thicknesses of line, if needed, can be drawn by changing the amount of pressure applied to the pencil. Paper quality is not critical, either. A good sketching paper is newsprint, although almost any kind of paper works. Use commonly available paper such as standard copy machine bond paper or notebook paper. Paper with a surface that is not too smooth is best. Many preliminary architectural designs have been created on a napkin at a lunch table. Sketching paper should not be taped down to the table. The best sketches are made when you are able to move the paper to the most comfortable drawing position. Some people make horizontal lines better than vertical lines. If this is your situation, move the paper so vertical lines become horizontal. Such movement of the paper may not always be possible, so it does not hurt to keep practicing all forms of lines for the best results. SKETCHING STRAIGHT LINES Lines should be sketched lightly in short, connected segments, as shown in Figure 5-. If you sketch one long stroke in one continuous movement, your arm tends to make the line curved rather than straight. If you make a dark line, you may have to erase it if you make an error. If you draw a light line, there is often no need to erase an error because it does not show up very much when the final lines are darkened to your satisfaction. Use the following procedure to sketch a horizontal straight line with the dot-to-dot method: STEP Mark the starting and ending positions or dots, as in Figure 5-2. The letters A and B are only for instruction. All you need are the points. STEP 2 Without actually touching the paper with the pencil point, make a few trial motions between the marked points to adjust your eye and hand to the anticipated line. MAKE STROKES FROM LEFT TO RIGHT AND BOTTOM TO TOP IF RIGHT-HANDED FIGURE 5- Sketching short line segments. A FIGURE 5-2 Step : Dot-to-dot. SHORT 2" 3" STROKES DOT-TO-DOT B 66

2 Chapter 5: Sketching Applications 67 A B FOR A Ø 6" CIRCLE FIGURE 5-3 Step 3: Short, light strokes. 3" R A B A B FIGURE 5-4 Step 4: Darken to finish the line. STEP 3 Sketch very light lines between the points by moving the pencil in short, light strokes, 2" to 3" long. With each stroke, attempt to correct the most obvious defects of the preceding stroke so the finished light lines are relatively straight (see Figure 5-3). STEP 4 Darken the finished line with a dark, distinct, uniform line directly on top of the light line. Usually the darkness can be obtained by pressing on the pencil (see Figure 5-4). SKETCHING CIRCULAR LINES The parts of a circle are shown in Figure 5-5. Three sketching techniques are used in making a circle: trammel, hand compass, and nail and string. Sketching Circles Using the Trammel Method A trammel is an instrument used for making circles. In this example, the instrument is a strip of paper. Use the following steps to sketch a 6" diameter circle using the trammel method: STEP To sketch a 6" diameter circle, tear or cut a strip of paper approximately " wide and longer than the radius of 3". On the strip of paper, mark an FIGURE 5-6 Step : Making a trammel. A 2 /2" " WIDE CENTER FIGURE 5-7 Step 2: Marking the radius with a trammel. approximate 3" radius with tick marks, such as A and B in Figure 5-6. STEP 2 Sketch a straight line representing the diameter at the place where the circle is to be located. On the sketched line, locate with a dot the center of the circle. Use the marks on the trammel to mark the other end of the radius line, as shown in Figure 5-7. Place the trammel next to the sketched line, being sure point B on the trammel is aligned with the center of the circle. STEP 3 Pivot the trammel at point B, making tick marks at point A as you rotate the trammel, as shown in Figure 5-8, until you have a complete circle, as shown in Figure 5-9. STEP 4 Lightly sketch the circumference over the tick marks to complete the circle, as shown in Figure 5-9. B X Y CENTER DIAMETER Ø C RADIUS R Z 3 A B CIRCUMFERENCE FIGURE 5-5 Parts of a circle. FIGURE 5-8 Step 3: Sketching the circle with a trammel.

3 68 Architectural Drafting and Design 4 5 FIGURE 5-9 Steps 4 and 5: Completing and darkening the circle. STEP 5 Darken the circle, as shown in Figure 5-9. You can darken the circle directly over the tick marks if your sketching skills are good, or if you are in a hurry. Sketching Circles Using the Hand-Compass Method The hand-compass method is a quick and fairly accurate way to sketch circles, although it takes some practice. Use the following steps to sketch a 6" diameter circle using the hand-compass method: STEP Be sure your paper is free to rotate completely around 360. Remove anything from the table that might stop such a rotation. STEP 2 To use your hand and a pencil as a compass, place the pencil in your hand between your thumb and the upper part of your index finger so your index finger becomes the compass point and the pencil becomes the compass lead. The other end of the pencil rests in your palm, as shown in Figure 5-0. FIGURE 5- Steps 4 and 5: Sketching a circle with the handcompass method. STEP 3 Determine the approximate radius by adjusting the distance between your index finger and the pencil point. Now, with the radius established, place your index finger on the paper at the proposed center of the circle. STEP 4 Using the established radius, keep your hand and pencil point in one place while you rotate the paper with your other hand. Try to keep the radius steady as you rotate the paper (see Figure 5-). STEP 5 You can perform Step 4 very lightly and then go back and darken the circle or, if you have had a lot of practice, you may be able to draw a dark circle as you go (see Figure 5-). Sketching Circles Using the Nail-and-String Method A method used to sketch large circles is to tie a pencil and a nail together with a string. The distance between the pencil and nail is the radius of the circle. When a large circle is to be sketched, use this method because the other methods do not work as well. This method is used with a nail driven at the center and a string connected to a pencil, for drawing large circles at a construction site. MEASUREMENT LINES AND PROPORTIONS FIGURE 5-0 Step 2: Holding the pencil for the hand-compass method. In sketching an object, all the lines that make up the object are related to each other by size and direction. In order for a sketch to communicate accurately and completely, it should be proportional to the object. The actual size of the sketch depends on the paper size and the desired size of the sketch. The sketch should be large enough to be clear, but the

4 Chapter 5: Sketching Applications 69 LINE TABLE LINE 2 FIGURE 5-2 Measurement lines. proportions of the features are more important than the size of the sketch. Look at the lines in Figure 5-2. How long is line? How long is line 2? Answer these questions without measuring either line; instead, relate each line to the other. For example, line can be described as half as long as line 2, or line 2 described as twice as long as line. Now you know how long each line is relative to the other. This relationship is called proportion. You do not know how long either line is in terms of a measured scale, but no scale is used for sketching, so this is not a concern. Whatever line you decide to sketch first determines the scale of the drawing, regardless of the actual length of the line. This first line sketched is called the measurement line. You relate all the other lines in your sketch to the first line. This is one of the secrets in making a sketch resemble the object being sketched. The second thing you must know about the relationship of the two lines in the example is their direction and position relative to each other. Do they touch each other? Are they parallel, perpendicular, or at some other angle to each other? When you look at a line, ask yourself the following questions (for this example use the two lines given in Figure 5-3):. How long is the second line? Answer: Line 2 is about three times as long as line. 2. In what direction and position is the second line relative to the first line? Answer: Line 2 touches the lower end of line with about a 90 angle between the lines. Carrying this concept a step further, a third line can relate to the first line or the second line, and additional lines can continue to relate in the same manner. Again, the first line drawn is the measurement line, which sets the scale for the entire sketch. This idea of relationship can also apply to spaces. In Figure 5-4, the location of a table in a room can be FIGURE 5-4 Spatial proportions. determined by spatial proportions. A typical verbal location for the table in this floor plan might be as follows: The table is located about one-half the table width from the top of the floor plan or about two table widths from the bottom, and about one table width from the right side or about three table widths from the left side of the floor plan. Using Your Pencil to Establish Measurements on a Sketch Your pencil can be a useful tool for establishing measurements on a sketch. When you are sketching an object that you can hold, use your pencil as a ruler. Place the pencil next to the feature to be sketched and determine the length by aligning the pencil tip at one end of the feature and marking the other end on the pencil with your thumb. The other end can also be identified by a specific contour or mark on the pencil. Then transfer the measurement to your sketch. The two distances are the same. Even though sketches do not require this accuracy, this is a quick way to establish measurement lines. A similar technique can be used to sketch a distant object. For example, to sketch a house across the street, hold your pencil at arm s length and align the pencil with a feature of the house, such as the house width. With the pencil point at one end of the house, place your thumb on the pencil, marking the other end of the house. Transfer this measurement to your sketch in the same orientation taken from the house. Repeat this technique for all of the house features until the sketch is complete. If you keep your pencil at arm s length and your arm straight, each measurement has the same accuracy and proper proportions. Block Technique for Sketching MEASUREMENT LINE FIGURE 5-3 Study the relationship between the two lines. Any illustration of an object can be surrounded overall with a rectangle or any other geometric shapes as shown in Figure 5-5. Before starting a sketch, visualize the object inside a rectangle. Then use the measurement-line

5 70 Architectural Drafting and Design FIGURE 5-7 Step 2: Block technique. Cut out the sections and lightly sketch the shapes. FIGURE 5-5 Block technique. technique with the rectangle, or block, to help determine the shape and proportions of your sketch. Sketching Procedures Using the Measurement-Line and Block Techniques You can sketch any object, such as an elevation, as you look at an actual house or a floor plan and think about how the features of the house relate to the measurement lines you learned previously. An elevation is an exterior view of a structure, which is the house in this case. To use the measurement-line and block techniques, follow these steps: STEP When you start to sketch an object, try to visualize the object surrounded with an overall rectangle. Sketch this rectangle first with very light lines. Sketch the rectangle in the proper proportion with the measurement-line technique, as shown in Figure 5-6. STEP 2 Cut sections out or away using proper proportions as measured by eye or using your pencil to establish measurements. Use light lines, as shown in Figure 5-7. WIDTH HEIGHT WIDTH THIS IS THE ELEVATION TO BE SKETCHED. THIS RECTANGLE IS IMPORTANT, ESTABLISHED AS OVERALL WIDTH AND HEIGHT OF VIEW. USE CONSTRUCTION LINES. FIGURE 5-6 Step : Sketch the block.

6 Chapter 5: Sketching Applications 7 FIGURE 5-2 Step 2: Evenly spaced grid sketched over the swimming pool. FIGURE 5-22 Steps 3 and 4: Proportioned box with a regular grid. FIGURE 5-8 Step 3: Darken the view. STEP 3 Complete the sketch by darkening the outlines desired for the finished sketch as shown in Figure 5-8. Sketching Irregular Shapes By using a frame of reference or an extension of the block method, irregular shapes can be sketched easily to their correct proportions. Follow these steps to sketch the free-form swimming pool shown in Figure 5-9: STEP Enclose the object in a lightly constructed box (see Figure 5-20). STEP 2 Sketch several evenly spaced horizontal and vertical lines, forming a grid, as shown in Figure 5-2. If you are sketching an object already drawn, draw your reference lines on top of the object lines to establish a frame of reference. Make a photocopy, and sketch on the photocopy if the original cannot be used. If you are sketching an object directly, you have to visualize these reference lines on the object you sketch. FIGURE 5-23 Step 5: Sketching the shape using a regular grid. FIGURE 5-24 Step 6: Darkening the object completely. STEP 3 On your sketch, correctly locate a proportioned box similar to the one established on the original drawing or object, as shown in Figure STEP 4 Use the drawn box as a frame of reference, and include the grid lines in correct proportion as shown in Figure STEP 5 Using the grid, sketch small, irregular arcs and lines that match the lines of the original object, as in Figure STEP 6 Darken the outline for a complete proportioned sketch, as shown in Figure FIGURE 5-9 Free-form swimming pool. FIGURE 5-20 Step : Imaginary box. INTRODUCTION TO MULTIVIEW SKETCHES A multiview, or multiview projection, is also known as orthographic projection. Multiview projection is the views of an object as projected upon two or more picture planes in orthographic projection. Orthographic projection is any projection of the features of an object onto an imaginary plane called a plane of projection, where the projection of the object s features is made by lines of sight that are perpendicular to the plane of projection. These terms

7 72 Architectural Drafting and Design TOP TOP FRONT RIGHT SIDE FRONT FIGURE 5-25 Multiviews. RIGHT SIDE FIGURE 5-26 Pictorial view. are traditionally used in drafting, but they are more commonly used in mechanical drafting for manufacturing. In architectural drafting such drawings are referred to as elevation views. Elevation views are two-dimensional views of an object, such as a house, that are established by a line of sight perpendicular to the surface of the object. When you make multiview sketches, follow a methodical order. Learning to make these sketches can help you later as you begin to prepare elevation drawings. 45 Multiview Alignment To keep your drawing in a standard form, sketch the front view in the lower left portion of the paper, the top view directly above the front view, and the rightside view to the right of the front view as shown in Figure The views needed may differ depending on the object. FIGURE 5-27 Step : Block out views and establish a 45 line. Multiview Sketching Technique The following describes how to sketch three basic views of a house: STEP Sketch and align the proportional rectangles for the front, top, and right side of the house given in Figure Sketch a 45 line to help transfer width dimensions. The 45 line is established by projecting the width from the proposed top view location across and the width from the proposed right-side view location up until the lines intersect, as shown in Figure STEP 2 Complete the shapes within the blocks, as shown in Figure FIGURE 5-28 Step 2: Block out shapes. STEP 3 Darken the lines of the object, as in Figure Remember to keep the views aligned for ease of sketching and understanding by others.

8 Chapter 5: Sketching Applications 73 STEP Sketch a horizontal reference line. You can consider this as the ground-level line. STEP 2 Sketch a vertical line perpendicular to the ground line somewhere near its center. This vertical line is used to measure height. STEP 3 Sketch two 30 angular lines, each starting at the intersection of the first two lines, as shown in Figure Making an Isometric Sketch The steps in making an isometric sketch from a multiview drawing or from a real object are as follows: FIGURE 5-29 Step 3: Darken all lines. ISOMETRIC SKETCHES Isometric sketches provide a three-dimensional (3D) pictorial representation of an object, such as the shape of a building. Isometric sketches are easy to draw and provide a fairly realistic 3D view of an object. An isometric sketch tends to represent objects as they appear to the eye. Such a sketch can help you visualize an object because three sides of the object are shown in a single three-dimensional view. Establishing Isometric Axes To establish isometric axes, you need four beginning lines: a horizontal reference line, two 30 angular lines, and one vertical line. Draw these lines as very light construction lines as shown in Figure Use the following steps to establish the isometric axes: STEP Select an appropriate view of the object to use as a front view, or study the front view of the multiview drawing. STEP 2 Determine the best position in which to show the object. STEP 3 Begin your sketch by setting up the isometric axes as previously described (see Figure 5-30). STEP 4 Using the measurement-line technique, sketch a rectangular box to the correct proportion, which surrounds the object to be sketched. Use the object shown in Figure 5-3 as an example. Imagine that the rectangular box represents a glass box that surrounds the object to be sketched inside. Begin to sketch the box by marking off the width at any convenient length. This is the width measurement line shown in Figure Next, estimate and mark the length and height relative to the measurement line (see Figure 5-33). Sketch the three-dimensional box by using lines parallel to the original axis lines (see Figure 5-33). The box must be sketched correctly; otherwise the rest of your sketch will be out of proportion. All lines drawn in the same direction must be parallel. Measure length of object along this line 3rd LINE 30 APPROXIMATELY Measure height of object along this line 2nd LINE st LINE GROUND LINE 4th LINE 30 APPROXIMATELY Measure depth of object along this line FIGURE 5-30 Isometric axes. FIGURE 5-3 Given structure.

9 74 Architectural Drafting and Design About /4 as long as width About /2 as long as width Width FIGURE 5-32 Step 4: Lay out length, width, and height. FIGURE 5-34 Step 5: Sketch the features of the structure. NONISOMETRIC LINES FIGURE 5-33 Step 4: Sketch the three-dimensional box. ISOMETRIC LINES STEP 5 Lightly sketch the features that define the details of the object. When you estimate distances on the rectangular box, you will find that the features of the object are easier to sketch in correct proportion than they would be if you tried to draw them without the box (see Figure 5-34). STEP 6 Darken all the outlines to finish the sketch, as shown in Figure Sketching Nonisometric Lines Isometric lines are lines on or parallel to one of the three original isometric axes. All other lines are nonisometric lines. Isometric lines can be measured in true length. Nonisometric lines appear either longer or shorter than their actual length (see Figure 5-35). You can measure and draw nonisometric lines by connecting their endpoints. Find the endpoints of the nonisometric lines by measuring along isometric lines. FIGURE 5-35 Step 6: Darken the structure. To locate where nonisometric lines should be placed, you have to relate to an isometric line. Sketching Isometric Circles and Arcs Circles and arcs appear as ellipses in isometric views. To sketch isometric circles and arcs correctly, you need to know the relationship between circles and the faces, or planes, of an isometric cube. Depending on which isometric plane the circle appears, isometric circles look like one of the ellipses shown in Figure The angle at which the isometric circle slants is determined by the surface on which the circle is to be sketched. Using the Four-Center Method to Sketch Isometric Circles The four-center method of sketching an isometric circle is fairly easy, but care must be taken to form the ellipse

10 Chapter 5: Sketching Applications 75 LEFT PLANE HORIZONTAL PLANE RIGHT PLANE FIGURE 5-36 Isometric circles arcs properly so the ellipse does not look distorted. Use the following steps to sketch isometric circles using the four-center method: STEP Sketch an isometric cube or box similar to Figure STEP 2 On each surface of the box sketch line segments connecting the 20 corners to the centers of the opposite sides as shown in Figure STEP 3 With points and 2 as the centers, sketch arcs beginning and ending at the centers of the opposite sides on each isometric surface (see Figure 5-39). STEP 4 On each isometric surface, with points 3 and 4 as the centers, complete the isometric circles by sketching arcs that meet the arcs sketched in Step 3 (see Figure 5-40). Sketching Isometric Arcs Sketching isometric arcs is similar to sketching isometric circles. First, block out the overall shape of the object. Next, establish the centers of the arcs. Finally, sketch the arc shapes. Remember that isometric arcs, just like isometric circles, must lie in the proper plane and have the correct shape CORNER 6 PLACES FIGURE 5-39 Step 3: Sketch arcs from points and 2. LEFT PLANE HORIZONTAL (TOP) PLANE ORTHOGRAPHIC PROJECTION Orthographic projection is any projection of features of an object onto an imaginary plane called a plane of projection. The projection of the features of the object is made by lines of sight that are perpendicular to the plane of projection. When a surface of the object is parallel to the plane of projection, the surface appears in its true size and shape on that plane. In Figure 5-4, the plane of projection is parallel to the surface of the object. The line of sight from the object is perpendicular to the plane of projection. Notice also that the object appears three-dimensional, which means the object has width, depth, and height. The view on the plane of projection is two-dimensional, which means the view has only width and height. In situations where the plane of projection is not parallel to the surface of the object, the resulting orthographic view is foreshortened, or shorter than the true length, as shown in Figure MULTIVIEW PROJECTION 3 FIGURE 5-40 Step 4: Sketch arcs from points 3 and RIGHT PLANE FIGURE 5-37 Step : Isometric cube. FIGURE 5-38 Step 2: Fourcenter construction of an isometric ellipse. As a review, multiview projection establishes two or more views of an object as projected on two or more planes by using orthographic projection techniques.

11 76 Architectural Drafting and Design OBJECT 5 2 PLANE OF PROJECTION LINES OF SIGHT PROJECTORS PERPENDICULAR TO PLANE OF PROJECTION LINES OF SIGHT PROJECTORS PERPENDICULAR TO PLANE OF PROJECTION PLANE OF PROJECTION ORTHOGRAPHIC VIEW ORTHOGRAPHIC VIEW FORESHORTENED ORTHOGRAPHIC VIEW OF SURFACE, 2, 3, 4 2 PLANE OF PROJECTION 2 5 TRUE SHAPE OF THE ORTHOGRAPHIC VIEW PLANE OF PROJECTION TRUE SHAPE ORTHOGRAPHIC VIEW OF SURFACE 2, 3, 5, 6 FIGURE 5-42 Projection of a foreshortened orthographic surface. FIGURE 5-4 Orthographic projection to form orthographic view. The result of multiview projection is a multiview drawing. Multiview drawings represent the shape of an object using two or more views. The six possible views include: the front, top, right side, left side, bottom, and rear. All six views are seldom used. Consideration should be given to the choice and number of views so, when possible, the surfaces of the object are shown in their true size and shape. If you can hold an object in your hands, you can visualize the views by turning the object until you are looking directly at a side. Continue turning the object, stopping to look at each view as your line of sight becomes perpendicular to the object surface. Figure 5-43 is a graphic representation of a person holding and rotating an object in this manner. As the object is rotated to each position, the person stops to look directly at the object surface. What the person sees at each of these positions is related to the specific multiview seen in proper positions within a set of multiviews in Figure Some people can visualize multiviews better than others. If you have difficulty visualizing views, pick up any object and try to sketch what you see as you rotate the object looking at each side. Holding an object and rotating to see the sides works well if you can pick up and hold the object. To see the views of your home, for example, go outside and stand so you can see the front of the house with your line of sight as perpendicular as possible to the front. This is the front view. You can do the same thing by walking around your home and stopping to look at each side in the same manner. Take a sketch pad and sketch what you see at each location, just like you do when holding an object. Elevations as Multiviews It is often easier to visualize a three-dimensional drawing of a structure than it is to visualize a two-dimensional drawing of the same structure. In architectural drafting, however, it is common to prepare construction drawings showing two-dimensional exterior views of a structure that provide representations of exterior materials or interior views of features such as kitchen and bath cabinets. These drawings are called elevations. The method used to draw elevations is multiview projection.

12 Chapter 5: Sketching Applications 77 TOP VIEW REAR VIEW LEFT-SIDE VIEW FRONT VIEW RIGHT-SIDE VIEW BOTTOM VIEW FIGURE 5-43 A graphic representation of a person holding and rotating an object. As the object is rotated to each position, the person stops to look directly at the object surface. What the person sees at each of these positions is related to the specific multiview seen in proper positions shown. A more detailed discussion of elevation drawing is found in Chapter 24 and Chapter 25. Figure 5-44 shows an object represented by a three-dimensional drawing, called a pictorial drawing, and three twodimensional views. This is the same object that the FRONT TOP OR PLAN VIEW SIDE TOP (PLAN VIEW) FRONT VIEW SIDE VIEW FIGURE 5-44 Comparison of a pictorial and a multiview presentation. person is holding in Figure Look at the object represented in Figure 5-43 and compare it to the pictorial and multiview drawing shown in Figure Using the Glass Box Viewing Method If you place the object in Figure 5-44 in a glass box so the sides of the glass box are parallel to the major surfaces of the object, you can project the surfaces of the object onto the sides of the glass box and create the multiviews shown in Figure Imagine the sides of the glass box are the planes of projection previously described. Look at Figure 5-45 again to see if you can visualize this idea. If you look at all sides of the glass box, you see the six views: front, top, right side, left side, bottom, and rear. Now, unfold the glass box as if the corners were hinged about the front view as demonstrated in Figure These hinge lines are commonly called fold lines.

13 78 Architectural Drafting and Design TOP TOP REAR LEFT FRONT RIGHT BOTTOM FIGURE 5-47 Glass box unfolded. FIGURE 5-45 Glass box. FRONT SIDE Completely unfold the glass box onto a flat surface, and you have the six views of an object represented in a multiview. Figure 5-47 shows the glass box unfolded. Notice also that the views are labeled: TOP front, top, right, left, bottom, and rear. Views are always found in this arrangement when using multiview projection. Now, analyze Figure 5-48 in detail so you see the features that are common among the views. Knowing how to identify the features of an object that are common among views can aid you later in the visualization of elevations. Notice again how the views are aligned in Figure The top view is directly above and the bottom view is directly below the front view. The left side is directly to the left and the right side is directly to the right of the front view. This alignment allows the drafter to project features from one view to the next to help establish each view. Now, look closely at the relationship of the front, top, and right-side views. A similar relationship exists using the left-side view. Figure 5-49 shows a 45 projection line established by projecting the fold or reference line (hinge) between the front and side view up, and the fold line between the front and top view over. All of the features established on the top view can be projected to the 45 line and then down onto the side view. This is possible because the depth dimension is the same in both the top and the side views. The reverse is also true. WIDTH FRONT SIDE TOP REAR LEFT FRONT RIGHT HEIGHT DEPTH BOTTOM FIGURE 5-46 Unfolding the glass box at hinge lines, also called fold lines. FIGURE 5-48 View alignment.

14 Chapter 5: Sketching Applications 79 FOLD LINE 45 Y X FOLD LINE FOLD LINE FOLD LINE X FIGURE 5-49 Establishing a 45 projection line. Features from the side view can be projected to the 45 line and then over to the top view. The transfer of features in Figure 5-49 using the 45 line can also be accomplished by using a compass with one leg at the intersection of the horizontal and vertical fold lines. The compass establishes the relationship between the top and side views, as shown in Figure Another method for transferring the size of features from one view to the next is the use of dividers to transfer distances from the fold line at the top view to the fold line at the side view. The relationship between the fold lines and the two views is shown in Figure 5-5. The front view is usually most important because it is the one from which the other views are established. There is always one common dimension between adjacent views. For example, the width is common between the front and top views and the height is common between the front and side views. This knowledge allows you to relate information from one view to another. Take one more look at the relationship of the six views, as shown in Figure FOLD LINE RADIUS FIGURE 5-5 Using dividers to transfer view projections. REAR LEFT FRONT FIGURE 5-52 Multiview orientation. Proper View Selection TOP BOTTOM There are six primary views that you can use to describe a structure completely. In architectural drafting, the front, left-side, right-side, and rear views are used as elevations to describe the exterior appearance of a structure completely. Elevation drawings are discussed in more detail in Chapter 24 and Chapter 25. The top view is called the roof plan view. This view shows the roof of the structure and provides construction information and dimensions. Roof plans are discussed in detail in Chapter 22 and Chapter 23. The bottom view is not used in architectural drafting. Y RIGHT FIGURE 5-50 Projection with a compass. FOLD LINE PROJECTION OF FEATURES FROM AN INCLINED PLANE When you use multiview projection, features of objects that are parallel to projection planes appear true size and shape, but features that are not parallel to projection planes are foreshortened, and are not in true size and shape.

15 80 Architectural Drafting and Design LINE OF INTERSECTION FORESHORTENED ROUND WINDOW ROUND WINDOW ROOF SKYLIGHT TRUE WIDTH PROJECTION LINES FIGURE 5-53 Rectangular features on an inclined plane. FIGURE 5-54 Round window is a circle when the line of sight is perpendicular. Rectangular Features on an Inclined Plane When a rectangular feature such as a skylight projects out of a sloped roof, the intersection of the skylight with the roof appears as a line when the roof also appears as a line. This intersection can then be projected onto adjacent views, as shown in Figure Circles on an Inclined Plane When the line of sight in a view is perpendicular to a circle, such as a round window, the window appears round, as shown in Figure When a circle is projected onto an inclined surface, such as a round skylight projected onto a sloped roof, the view of the inclined circle is elliptical, as shown in Figure TOP (ROOF PLAN) FRONT FORESHORTENED DIAMETER MINOR DIAMETER SKYLIGHT DIAMETER MAJOR DIAMETER SKYLIGHT DIAMETER MAJOR DIAMETER ROUND SKYLIGHT FORESHORTENED DIAMETER MINOR DIAMETER SIDE FIGURE 5-55 Circle projected onto an inclined surface appears as an ellipse. CADD APPLICATIONS Using CADD for Conceptual Design and Presentation Sketches Google SketchUp is a CADD program that can be used to create, share, and present three-dimensional models with an easy-to-use interface. Interface, also called user interface, is the term describing the tools and techniques used to provide and receive information to and from a computer application. Google SketchUp is often used in the conceptual design phase of a project and to create presentation drawings that look hand-sketched, as shown in Figure Tools such as Line, Arc, Rectangle, and Circle are used to sketch two-dimensional (2D) closed boundaries, known as faces. Then, tools such as the Push/Pull, Follow-Me, and Move are used to pull faces and edges into three-dimensional (3D) objects (see Figure 5-57). CADD graphic and image files can be imported into Google SketchUp, and then traced over with sketch tools to create quick 3D models for design studies (see Figure 5-58).

16 Chapter 5: Sketching Applications 8 CADD APPLICATIONS FIGURE 5-56 Google SketchUp can be used in the conceptual design phase to sketch new ideas and designs. Courtesy Ron Palma, 3D-DZYN. FIGURE 5-57 In Google SketchUp, use sketch lines to create faces, then push/pull the faces into 3D geometry. Courtesy Ron Palma, 3D-DZYN.

17 82 Architectural Drafting and Design CADD APPLICATIONS FIGURE 5-58 Google SketchUp lines are traced over an imported image to create a 3D model. Courtesy Ron Palma, 3D-DZYN. In addition to sketching and modeling tools, Google SketchUp can be used to add finish materials, hand-sketched styles, and shadows to create presentation drawings as shown in Figure Custom appearances can be used to create a sampling of different presentation styles. When Google SketchUp is combined with Google Earth, a location from Google Earth can be found and imported into Google SketchUp. A new design idea is sketched relative to the Google Earth location. The Google SketchUp file is then imported back into Google Earth to create a 3D presentation file of the design within Google Earth as shown in Figure Google SketchUp is available for download from the Google Web site and comes in two formats. Google SketchUp is a free download and allows you to create 3D models very quickly. Google SketchUp Pro is a premium version and includes all of the tools from the free version plus advanced settings for commercial use and interaction with other CADD programs. FIGURE 5-59a Apply different materials and sketch styles to 3D model geometry to create unique presentation drawings. Courtesy Ron Palma, 3D-DZYN.

18 Chapter 5: Sketching Applications 83 CADD APPLICATIONS FIGURE 5-59 b Continued FIGURE 5-60 Use Google Earth to import a site into Google SketchUp, design the 3D model, then send the model back to Google SketchUp for design review. Courtesy Ron Palma, 3D-DZYN.

19 84 Architectural Drafting and Design ADDITIONAL RESOURCES See CD for more information The following Web sites can be used as a resource to help you find information related to sketching applications. Address Company, Product, or Service Google Sketch Up Sketching lessons and tutorials Sketching Applications Test See CD for more information QUESTIONS DIRECTIONS: Answer the following questions with short, complete statements or drawings as needed on an 8 /2" " sheet of notebook paper, or complete the electronic chapter test on the Student CD.. Letter your name, Chapter 5 Test, and the date at the top of the sheet. 2. Letter the question number and provide the answer. You do not need to write the question. Answers can be prepared on a word processor if approved by your course guidelines. Question 5 Define sketching. Question 5 2 How are sketches useful in CADD? Question 5 3 Describe the proper sketching tools. Question 5 4 Should paper for sketching be taped to the drafting board or table? Why or why not? Question 5 5 What kind of problem can occur if a long, straight line is drawn without moving the hand? Question 5 6 What type of paper should be used for sketching? Question 5 7 Briefly describe a method that can be used to sketch irregular shapes. Question 5 8 Define isometric sketch. Question 5 9 What is the difference between an isometric line and a nonisometric line? Question 5 0 What do proportions have to do with sketching techniques? Question 5 Define orthographic projection. Question 5 2 What is the relationship between the orthographic plane of projection and the projection lines from the object or structure? Question 5 3 When is a surface foreshortened in an orthographic view? Question 5 4 How many principal multiviews of an object are possible? Question 5 5 Give at least two reasons why the multiviews of an object are aligned in a specific format. Question 5 6 In architectural drafting, what are the exterior front, right-side, left-side, and rear views also called? Question 5 7 If a round window appears as a line in the front view and the line of sight is perpendicular to the window in the side view, what shape is the window in the side view? Question 5 8 If a round skylight is positioned on a 5/2 roof slope and appears as a line in the front view, what shape is the skylight in the side view? Question 5 9 Briefly describe the trammel method for sketching a circle. Question 5 20 Why must the paper be free to rotate when you are using the hand-compass method for sketching a circle? Question 5 2 What is the distance from the center of a circle to the circumference called? Question 5 22 Name the distance that goes all the way across a circle and passes through the center. Question 5 23 Describe an easy way to sketch a 5" circle on paper and a 6' 6" circle at a construction site. Question 5 24 In a short but complete paragraph, discuss the importance and use of measurement lines and proportions in sketching objects.

20 Chapter 5: Sketching Applications 85 Question 5 25 Briefly describe how the block technique works for making sketches of objects. Question 5 26 Name two basic applications for multiviews in architectural drafting. Question 5 27 In multiview projection, what is the top view commonly called? Question 5 28 Name the four views that are commonly used as elevations to describe the exterior appearance of a structure. Question 5 29 Why should a soft lead and slightly rounded pencil point be used when sketching? Question 5 30 Briefly describe how you would use your pencil to establish measurements if you were sketching a house across the street. elements large enough to fill most of an 8 /2 " sheet of paper. PATIO SWIMMING POOL PROBLEMS DIRECTIONS: On 8 /2" " bond paper or newsprint, use proper sketching materials and techniques to solve the following sketching problems. Use very lightly sketched construction lines for all layout work. Darken the lines of the object, but do not erase the layout lines. Additional problems are available on the Student CD. Problem 5 Sketch the front view of your home or any local single-family residence using the block technique. Use the measurement-line method to approximate proper proportions. Problem 5 2 Use the box method to sketch a circle with a diameter of approximately 4". Sketch the same circle using the trammel and hand-compass methods. Problem 5 3 Find an object with an irregular shape, such as a French (irregular) curve, and sketch a two-dimensional view using the grid method. Sketch the object to correct proportions without measuring. Problem 5 4 Use the same structure you used for Problem 5, or a different structure, to prepare an isometric sketch. Problem 5 5 Use the same structure you used for Problem 5 to sketch a front view and right-side view. Problem 5 6 Use a scale of /4" = ' 0" to draw a 38 acute angle with one side horizontal and both sides 8' 6" long. Problem 5 7 Given the sketch for this problem of a swimming pool, spa, and patio, resketch these SPA Problem 5 8 Given the top and side views shown in the sketch for this problem, redraw these views and draw the missing front view, filling most of an 8 /2 " sheet of paper. START VIEW HERE

21 86 Architectural Drafting and Design Problem 5 9 Given the pictorial sketch for this problem, draw the front, top, and right-side views, filling most of an 8 /2 " sheet of paper. Problem 5 0 Given the three views of the house shown in the sketches for this problem, sketch an isometric view, filling most of an 8 /2 " sheet of paper. FRONT