Module Five: Pictorial Drawings


Objectives

Introduction

Oblique Projections

Axonometric Projections

Putting it all Together

Test


Unit Objectives

Pictorial Drawings


Foundational Objective

Common Essential Learnings Foundational Objectives

Learning Objectives


Pictorial Drawings


Pictorial drawing is the oldest written method of communication known. A major value of pictorial drawings is that they show objects three-dimensionally. Engineering drawings, with all their dimensions and multiple views, are difficult to read for an untrained person. A pictorial drawing, on the other hand, can be viewed and understood by individuals with no background in engineering design.

img3.jpg (5778 bytes)
Cavalier Oblique
Projection
img4.jpg (4208 bytes)
Cabinet Oblique
Projection
img5.jpg (6065 bytes)
Isometric
Projection

Pictorial drawings have many industrial uses. They are often included on engineering drawings to clarify a detail. Sometimes, a section is shown pictorially. Maintenance manuals and parts manuals rely heavily on pictorial drawings. Often an assembly is drawn in an exploded view. This shows the relationships of the parts and their order of assembly.

img1.jpg (70291 bytes)
Exploded Isometric Assembly

Shaded pictorial drawings are used extensively in sales literature. Architectural perspectives show the exteriors of buildings, the areas surrounding the building, and the interiors of rooms. Most pictorial drawings are made by a special type of drafter, the technical illustrator. These individuals have artistic ability and special preparation.


Oblique Projection


In oblique projections the front view is drawn true size, and the receding surfaces are drawn on an angle to give it a pictorial appearance.This form of projection has the advantage of showing one face (the front face) of the object without distortion. Generally, the face with the greatest detail faces the front.

There are two types of oblique projection used in engineering design.


Cavalier Oblique

In cavalier oblique drawings, all lines (including receding lines) are made to their true length.

img8.jpg (11598 bytes)


Cabinet Oblique

In cabinet oblique drawings, the receding lines are shortened by one-half their true length to compensate for distortion and to approximate more closely what the human eye would see. It is for this reason that cabinet oblique drawings are the most used form of oblique drawings.

img7.jpg (10949 bytes)


Typical Angles of Projection

In oblique drawings, the three axes of projection are vertical, horizontal, and receding. The front view (vertical & horizontal axis) is parallel to the frontal plane and the other two faces are oblique (receding). The direction of projection can be top-left, top-right, bottom-left, or bottom-right. The receding axis is typically drawn at 60, 45, or 30 degrees.

Top Left                                                         Top Right
img6.jpg (31711 bytes)
Bottom Left                                                     Bottom Right


Practice Activity

I strongly suggest that you open AutoCAD LT and try these practice activities before tackling the assigned activities for this unit.

We will be using English units (inches) in all the samples below.

Let's assume we wish to create an Oblique projection of the following object.

img42.jpg (7444 bytes)

When the front and rear faces are identical (as in the object above), there are two approaches to creating the oblique projection. I will introduce both methods.


Method 1

In the drawing above, there are only two planes of depth (front and back). Generally the frontal plane is drawn first.

img43.jpg (3870 bytes)

Then draw the receding lines (true length for cavalier oblique and 1/2 length for cabinet oblique drawings).

The start point of each line is snapped
to the intersection. The end point is
entered using relative polar coordinates
@1.5<30
img44.jpg (5704 bytes)
Cavalier
The start point of each line is snapped
to the intersection. The end point is
entered using relative polar coordinates
@0.75<30

img45.jpg (4188 bytes)
Cabinet

Then connect the appropriate lines on the back plane.

img46.jpg (5122 bytes)
Cavalier
img47.jpg (3051 bytes)
Cabinet

 


Method 2

Draw the front plane.

img43.jpg (3870 bytes)

If the back plane is identical to the front plane, then copy and place the duplicate at the appropriate angle and distance from the front plane.

Use the copy command. Use
any intersection as a base point
and then place the duplicate using
relative polar coordinates
@1.5<30
img48.jpg (3341 bytes)
Cavalier
Use the copy command. Use
any intersection as a base point
and then place the duplicate using
relative polar coordinates
@0.75<30
img49.jpg (2799 bytes)
Cabinet

Then connect the two planes with the receding lines.

img50.jpg (5299 bytes)
Cavalier
img51.jpg (3515 bytes)
Cabinet

Then trim away any hidden details.

img46.jpg (5122 bytes)
Cavalier
img47.jpg (3051 bytes)
Cabinet

Circular Features

Let's assume we wish to create an Oblique projection of the following object.

img52.jpg (9997 bytes)

In this case, you need to construct the front and rear planes first.

Use the copy command. Use
the center as a base point
and then place the duplicate using
relative polar coordinates
@1.5<30

img53.jpg (5261 bytes)
Cavalier
Use the copy command. Use
the center as a base point
and then place the duplicate using
relative polar coordinates
@0.75<30

img54.jpg (4306 bytes)
Cabinet

Then snap receding tangent lines connecting the two planes.

img55.jpg (6008 bytes)
Cavalier
img56.jpg (4380 bytes)
Cabinet

Then trim away any hidden details.

img57.jpg (5746 bytes)
Cavalier
img58.jpg (3990 bytes)
Cabinet

Activity 5 - 1
(Guided)


Create a Cabinet Oblique drawing of the following object. In addition, create a layout (scale 1:1) with title block.

img9.jpg (52242 bytes)
Units: inches


To help ease your transition into oblique projections, I will guide you through this first drawing.


The direction of projection and the receding angle is a matter of personal preference. However, once a direction of projection and receding angle is chosen, you cannot change it. In this activity, we will project to the top-right.

The receding axis angle is typically one of 30, 45, or 60 degrees. We will project at an angle of 30 degrees.

Given that we are creating a Cabinet Oblique, the receding line (depth) is exactly 1/2 the true length.

Create a new drawing from Scratch and select English units (feet and inches).

To be consistent with my drafting settings, set your Snap to 0.2 and your Grid to 1.0 (Tools - Drawing Aids).

As mentioned in the previous section, the front view (vertical & horizontal axis) is parallel to the frontal plane and the other two faces are oblique (receding).

In oblique drawings, the most forward portion of the front view is usually drawn first. In the image below, the forward most section of the frontal plane is outlined. The portions crossed-out belong to a deeper portion of the front plane and will be drawn later.

img14.jpg (38431 bytes)

Set your origin to a location convenient for you and then draw the most forward portion of the frontal plane using the dimensions provided. Be precise. The start and end of the angled lines can be derived exactly. 

img15.jpg (4295 bytes)

The most frontal plane is now completed. We must now begin moving back deeper into the drawing.

Determining which plane to draw next is often a matter of personal preference. In the case of this drawing, the most frontal plane is identical to the plane furthest back. So, it makes sense to duplicate the portion of the drawing just created and then place the duplicate at the correct depth (along the receding axis).

Let's now draw the rear-most plane.

Set your origin to the intersection indicated below (be precise - use your snaps if necessary).

img17.jpg (6029 bytes)

Select the Copy tool and drag a box around all the lines drawn and then press the Enter key.

img18.jpg (8262 bytes)

The command line will then ask for a base point. Select the bottom corner as your base point.

Then, the command line will ask for a displacement. We wish to recede at an angle of 30 degrees and at a depth of 1 (1/2 the actual depth).

Enter the displacement location relative to the base point by typing 1<30 on the command line (see below).

img19.jpg (47197 bytes)

Then press the Enter key. You should see the following:

img20.jpg (8065 bytes)

Next, insert the receding lines that connect the front and rear planes (be sure to use your snap tool).

img21.jpg (13520 bytes)

Next, trim away any lines that would be hidden from view.

img22.jpg (12208 bytes)

Let's now move back up to the most frontal plane and start filling in some of the missing detail.

The next plane we will draw is outlined in the image below. The depth of the next plane is circled in red.

img16.jpg (39444 bytes)

Move to the intersection indicated below.

img23.jpg (14481 bytes)

Draw a receding line (length - .1, angle 30 degrees) from the origin. Remember that in cabinet oblique drawings, receding line length is 1/2 true size. When drawing the receding line, I suggest selecting your origin (0, 0) as the first point and then specify the second point relative to the origin (0.1<30) using manual polar coordinate entry.

img24.jpg (13917 bytes)

Copy the line just drawn and place a duplicate in the locations indicated below. Be sure to use your snaps.

img25.jpg (14413 bytes)

Next, draw the vertical line indicated below (length - 0.4 true height).

img26.jpg (13634 bytes)

Then duplicate the line in the other two locations.

img27.jpg (15581 bytes)

Next, connect the lines to finish the front and oblique faces.

img28.jpg (13454 bytes)

You will then need to trim away lines hidden from view (see below). You will likely need to zoom in to perform this task.

img29.jpg (5718 bytes)
Before
img30.jpg (2824 bytes)
After

The next plane we will draw is indicated by arrows in the image below. The dimensions needed for the next plane are circled.

img31.jpg (41302 bytes)

We will need a reference point to measure from in order to draw the triangular features.

Move to the following location as your origin.

img32.jpg (16831 bytes)

Then re-locate the origin to the location where the first triangle is to be drawn. Remember that the start location of the first triangle is 1/2 the true distance from the front plane. Use polar coordinates to locate the new origin (0.4<30).

img33.jpg (16526 bytes)

Then draw the first triangle (true size).

img34.jpg (6724 bytes)

Copy and place a duplicate of the triangle 0.2 units and 30 degrees away from the original (0.2<30).

img35.jpg (7035 bytes)

Then insert any lines needed to complete the detail and trim away any hidden features.

img36.jpg (8608 bytes)

Let's now do the other side.

Set your origin to the following location.

img37.jpg (18517 bytes)

Relocate your origin one more time to the location where the triangle is to be drawn. Again,  the start location of the triangle is 1/2 the true distance from the front plane. Use polar coordinates to locate the new origin (0.4<30).

img38.jpg (8884 bytes)

Then draw the triangle true size.

img39.jpg (7618 bytes)

Finally, trim away any hidden detail.

img40.jpg (15543 bytes)

Your Cabinet Oblique Projection is now complete.

Your final step is to create a layout, complete with title block.

img41.jpg (25193 bytes)


Save the drawing as "pd1" (pictorial drawing) inside your Unit5 folder.


Axonometric Projections


Axonometric projection is the projection of an object onto a drawing surface with the object positioned so that it appears three-dimensional. There are three types of axonometric projection. However, in this course, we will focus on the Isometric method of projection.

Consider the following object:

img59.jpg (13347 bytes)

Isometric drawing of the above object:

img60.jpg (7206 bytes)

The word isometric means "having equality of measure". This means that the object is placed with its major edges at equal angles with the drawing plane.

Isometric Cube
img61.jpg (11315 bytes)
Three Equal Angles

In isometric drawings, the vertical edges are drawn vertically on the drawing surface and the horizontal surfaces are rotated 30 degrees.

img62.jpg (10686 bytes)

When creating isometric drawings manually (using pencil and paper), all lines are 80% of their true length. The drafter must manually convert each line segment before drawing the line.

Using CAD, the isometric drawing is generally drawn true size and then it is scaled down using the scale tool.

img59.jpg (13336 bytes)

Above object drawn using
true-size lines
img63.jpg (9049 bytes)

Appears disproportionately large
Above object drawn using
true-size lines and then
scaled to 80% actual size.
img64.jpg (7125 bytes)
More accurately depicts
size of actual object

Practice Activity

I strongly suggest that you open AutoCAD LT and try these practice activities before tackling the assigned activities for this unit.

We will be using English units (inches) in all the samples below.

AutoCAD LT contains several tools used specifically in creating isometric drawings. The most important of which is the isometric snap mode.

From your menu, select the Tools - Drawing Aids item. Make sure Isometric snap is selected (see below).

img65.jpg (53518 bytes)

You will notice that your grid pattern and mouse cursor change shape.

img66.jpg (9479 bytes)

Once you set the snap style to Isometric, you can work on any of three planes, each with an associated pair of axes:

  • Left. Aligns snap and grid along 90- and 150-degree axes.
  • Top. Aligns snap and grid along 30- and 150-degree axes.
  • Right. Aligns snap and grid along 30- and 90-degree axes.

img67.jpg (16828 bytes)

Choosing one of the three isometric planes causes Ortho and the crosshairs to be aligned along the corresponding isometric axes. For example, when Ortho is on, the points you specify align along the simulated plane you are drawing on. Therefore, you can draw the top plane, switch to the left plane to draw another side, and switch to the right plane to complete the drawing.

img68.jpg (21218 bytes)

To toggle between Left, Right, and Top modes, use the F5 key. Notice how the cursor changes shape to align with the axis.

img69.jpg (5330 bytes)
Left Mode
img70.jpg (4969 bytes)
Top Mode
img71.jpg (5144 bytes)
Right Mode

Let's assume we wish to create an isometric drawing of the following solid block:

img42.jpg (7444 bytes)
Orthographic drawing

img73.jpg (4946 bytes)
Finished Isometric

To do this practice activity, use the default grid (0.5) and snap (0.5) settings. Make sure your Isometric snap is on. For this first exercise, we will be using the isometric grid and snap settings to draw the isometric.

Lets start with the Left mode. Press the F5 key until your cursor looks as follows:

img72.jpg (1423 bytes)

Make sure that your coordinate display is set to indicate relative polar coordinates. To do this, select any drawing tool (such as line) and then click anywhere on your drawing area to indicate the first point.

While you are still in drawing mode, click your right mouse button on top of the coordinate display.

img74.jpg (3662 bytes)

If your coordinate display is set to relative, then the word Relative will appear grayed out.

Press the Esc key to get out of drawing mode.

Let's begin drawing. Make sure your grid and snap are turned on.

Select the Line tool and click on any point somewhere in the middle of your drawing area. Then pull a line down exactly 1 unit (use the coordinate display).

img75.jpg (22703 bytes)

Then pull a line exactly 1.5 units to the left (along the isometric axis). Use the shape of your mouse cursor as an aid to find the axis.

img76.jpg (20448 bytes)

Then pull a line exactly 1 unit up.

img77.jpg (20339 bytes)

Then pull a line back to where you started and press the Enter key.

img78.jpg (2876 bytes)

Next, switch your isometric snap (F5) to Right and then draw the right plane of the object.

img79.jpg (4029 bytes)

Then, switch your isometric snap to Top and then finish drawing the object.

img80.jpg (5136 bytes)

In the simple example above, all of the points happened to fall neatly on the grid. In most real life design situations, this will not always be the case. Under those circumstances, you will need to enter coordinates manually. This will be demonstrated in the first isometric guided activity later on.

I will now demonstrate drawing circular isometric features. Take, for example, the following object.

img52.jpg (9997 bytes)
Orthographic drawing

img81.jpg (4688 bytes)
Finished Isometric

Many CAD applications have a feature that allows the drawing of isometric circles.

We will start by drawing the isometric circle first.

Switch to the Right isometric plane.

Then type "ellipse" on the command line and then press the Enter key or press the ellipse button img141.jpg (1141 bytes) on the drawing toolbar.

img82.jpg (25710 bytes)

The command line then asks you to select from one of three options. Enter I or i for Isocircle.

The command line will then ask you to specify the center of the Isocircle. Select a point somewhere in the middle of your drawing area using your mouse.

img84.jpg (7723 bytes)

Then specify the radius of the isocircle (0.5) and then press the Enter key. You can also specify the diameter by entering d or D on the command line and then entering the diameter.

img83.jpg (12135 bytes)

img85.jpg (3412 bytes)
Isocircle

Next, using the Origin UCS tool, set the current origin to the center of the isocircle (snap to center).

img86.jpg (5069 bytes)

Next, draw another isocircle 1.5 units from the origin and at an angle of 150 degrees.

Use the same steps indicated above. When the command line asks for the center of the Isocircle, enter the absolute coordinates of 1.5<150.

img87.jpg (7387 bytes)

Next, connect the two isocircles using lines (snap to quadrant).

img88.jpg (5035 bytes)

Then, trim away the hidden portion of the second isocircle.

img89.jpg (4810 bytes)


Connecting Isometric Circles


In the previous section, you were shown how to create isometric cylinders.

img89.jpg (4810 bytes)

You did this by drawing two isometric circles and connecting them using the quadrant snap. These quadrant locations were also tangent locations for the isocircles. This works fine for isocircles of the same size and along the same isometric axis.

However, there are times when you need to connect isocircles of different sizes. Look at what happens when you try to connect isocircles of different sizes using the quadrant snap.

img135.jpg (20912 bytes)

Note that the lines are not tangent to the isocircles. Snapping to tangents of ellipses or isocircles is not supported very well using AutoCAD. When you try to connect isometric circles or ellipses using the tangent snap, you get very inconsistent results. 

To snap lines tangent to ellipses or isocircles, you must perform the following steps in the exact order indicated.

Open AutoCAD and create a new drawing in English units. The Drawing Area is not relevant for this practice exercise.

Next switch to Isometric mode (Top) and draw two isocircles (Diameters 2.5 and 0.5 units) with the larger isocircle 2.0 units directly above the lower isocircle (see below).

img136.jpg (12303 bytes)

It's important that you follow the steps below in the correct order.

Let's do the left side first.

Select the line tool and snap a line (snap to nearest, snap to quadrant) from anywhere on the smaller isocircle to a location close to where the tangent is likely to be on the larger isocircle (the line must touch both isocircles). The correct order is important (smallest isocircle and then larger isocircle).

img137.jpg (13574 bytes)

Then, delete the line just drawn. After you've deleted it, use the line tool to draw a line from the smaller isocircle to the larger isocircle (in that order) using the snap to tangent tool for each isocircle. You will notice the point of tangent will anchor for both isocircles.

img138.jpg (13591 bytes)

To connect the other side, you need to repeat the same steps. Draw a line from one isocircle to the other isocircle close to the intended tangent locations (the line must touch the isocircles). Then delete the line and then snap a line from one isocircle to the other using snap to tangent. Again, the isocircles must be selected in the same order used to draw the first line.

img139.jpg (15260 bytes)
Isocircles connected using tangent lines


Activity 5 - 2
(Guided)


Create an Isometric drawing of the following object. In addition, create a layout (scale 1:1) with title block. When the drawing is done, you do not need to scale the isometric drawing down to 80%.

img11.jpg (54113 bytes)
Units: mm


To help ease your transition into Isometric drawings, I will guide you through this first drawing.


Create a new drawing from Scratch and select Metric units (mm).

To be consistent with my drafting settings, set your Snap to 10 and your Grid to 10 (Tools - Drawing Aids).

I will introduce a few new techniques that will help you layout isometric drawings. With complex objects such as the object you are about to draw. It is necessary to break the drawing up into sections. The section you choose to draw first is arbitrary. We will begin by drawing the section outlined in red below. The overall length and width of the section indicated are also circled in red.

img90.jpg (53869 bytes)

Start by setting your Isometric Snap to On (Tools - Drawing Aids).

Then set the Isometric snap mode to Top (see below). Remember that the F5 key can be used to toggle between the three modes (Left, Right, and Top).

img91.jpg (15695 bytes)

Set Your Origin UCS to somewhere in the middle of your drawing area (see below).

Your coordinate display should be set to display relative coordinates.

img92.jpg (20753 bytes)

We are now ready to begin drawing. When creating isometric detail that is complex in shape, it is easiest to place the detail inside of a rectangular isometric bounding box. The bounding box must be exactly the same size (length and width) as the detail being drawn. Let us now create the bounding box for the detail indicated below.

img93.jpg (41321 bytes)

Select the Line tool and indicate the first point (0, 0). Set the second point to the relative coordinate of 70<150 and then press Enter. You can use your grid as a guide. Press the Esc key to get out of Line mode.

img94.jpg (6698 bytes)

Select the Line tool again and indicate the first point (0, 0). Set the second point to the relative coordinate of 58<30 and then press Enter. Press the Esc key to get out of Line mode.

img95.jpg (10317 bytes)

Finish the isometric bounding box by duplicating each of the two existing lines and snapping them into their correct location (see below).

img96.jpg (13508 bytes)

The bounding box created above will house all the detail for this section. We are now going to mark the locations of important intersections needed to construct the detail for this section. To do this we will be using the Point tool.

Set your Point tool to a shape of your choice (that is easily recognizable) using Format - Point Style.

img97.jpg (29680 bytes)

There are several methods that can be used to locate the points for important intersections. The method I am about to demonstrate will require the moving of the current origin UCS. Let's now mark the following locations on our bounding box.

img98.jpg (31969 bytes)

When placing points, pick any corner of your bounding box to be your origin. Then using the dimensions indicated above, place as many points as you can easily define in the box. When done, move your origin to a new location and place more points.

I will demonstrate the first few points starting in the lower right corner of the bounding box.

Make sure your origin is set to the following location.

img99.jpg (13738 bytes)

Using your Point tool place points at the following coordinates:

img100.jpg (13806 bytes)

Then move your origin to other convenient locations and finish placing the rest of the points. You will likely need to snap your origin to another point or a midpoint of a line to finish placing all the points. Remember - be precise.

img101.jpg (14013 bytes)
All Points Located

Next, connect the points using your line tool (see below). Be sure to use the Snap to Node when creating the lines.

img102.jpg (16164 bytes)

When done, you can remove the points and delete any unwanted lines (see below).

img103.jpg (12830 bytes)

Let's now duplicate the above detail and place the duplicate exactly 12 units below the existing one.

Set your origin to the following intersection.

img104.jpg (14780 bytes)

Select the Copy tool and then select all of the existing lines and then press the Enter key.

When the command line asks for a base point, specify the same intersection as the origin using your mouse & snap or by entering (0, 0) on the command line.

img105.jpg (17390 bytes)

When the command line asks for the first point as displacement, enter the absolute coordinates 12<270.

img106.jpg (22488 bytes)
Copy Properly Placed

Next, connect the related intersections using the Line tool and then delete/trim any detail hidden from view.

img107.jpg (18475 bytes)
Completed Top Section

Using the existing detail, we can now move on to another portion of the object.

Change your Isometric Snap mode to Left and set the following intersection as your origin.

img108.jpg (17791 bytes)

We will now complete the following detail indicated in red. The dimensions we will require are also circled in red.

img109.jpg (52731 bytes)

Start by creating a line exactly 52 (64-12) units long and extending downwards vertically from the origin (52<270).

img110.jpg (19424 bytes)

Move your origin to the following location.

img111.jpg (19004 bytes)

Place a point 12 units to the right of the origin along the isometric axis (12<-30).

img112.jpg (20125 bytes)

Draw a line starting at the point and extending down vertically exactly 52 units long (@52<270).

img113.jpg (20880 bytes)

Change to Right mode and draw a line from the endpoint of the previous line extending to the right (along the isometric axis) exactly 58 units long (@58<30).

img114.jpg (21744 bytes)

From the endpoint of that line, draw a line extending vertically up exactly 52 units long (@52<90).

img115.jpg (22387 bytes)

Then trim away any line sections hidden from view.

img116.jpg (21421 bytes)

You can also trim away the portion of the line to the left of the point (placed earlier) and then remove the point (see below).

img117.jpg (22420 bytes)

Our next step is to build a bounding box that will contain the lower portion of the object.

Set your origin to the following intersection.

img118.jpg (22075 bytes)

We will now complete the following detail indicated in red. The dimensions we will require are also circled in red.

img119.jpg (32416 bytes)

From the dimensions given above, we can extrapolate mathematically the size of the bounding box needed (from the previously defined origin) - 72 x 58.

Change your Isometric mode to Top.

Draw a line from the origin (0, 0) extending to the left (along the isometric axis) exactly 72 units long (72<150).

img120.jpg (27577 bytes)

Move your origin to the endpoint of the line just drawn and create another line from the endpoint extending to the right (along the isometric axis) exactly 58 units long (58<30).

img121.jpg (27924 bytes)

Copy the line indicated below and snap the duplicate to the endpoint of the line just drawn.

img122.jpg (31255 bytes)

Then place points at the important intersections (i.e. 12 & 22 units from the corners).

img123.jpg (28858 bytes)

Then use the Line tool to connect the points and then delete the points and trim the lines.

img124.jpg (28171 bytes)

Copy the lower section and place the duplicate 12 units above the section just created.

img125.jpg (30286 bytes)

Then connect any necessary intersections and trim away any lines hidden from view.

img126.jpg (27426 bytes)

Let's now build the feature indicated below.

img127.jpg (54270 bytes)

Place your origin at each of the following intersections and then place your reference points (22<30 & 36<30 from each origin).

img128.jpg (30195 bytes)

Then connect the relevant points using the Line tool. Not all the points need to be connected (some of the lines are hidden from view). Often it does not become evident which lines are needed until all the points are placed.

img129.jpg (29842 bytes)

Then trim away any lines hidden from view. You can also delete the points used for construction purposes.

img130.jpg (28339 bytes)
Completed Isometric View

The last step is to create the layout with title block.

img131.jpg (28065 bytes)


Save the drawing as "pd2" (pictorial drawing) inside your Unit5 folder.


Activity 5 - 3


Create an Isometric drawing of the following object. In addition, create a layout (scale 1:1) with title block. When the drawing is done, you do not need to scale the isometric drawing down to 80%.

img12.jpg (60198 bytes)
Units: mm

Sample
img133.jpg (27545 bytes)


Save the drawing as "pd3" (pictorial drawing) inside your Unit5 folder.


Putting It All Together


Pictorial drawings are rarely used in isolation of other types of drawings. A complete set of engineering drawings usually include orthographic projections as well as one or more pictorial drawings (depending on the product's detail). Adding a pictorial drawing provides the viewer with a more complete picture of the object.

img134.jpg (24333 bytes)

The orthographic views are always drawn first. All the rules regarding the spacing and alignment of orthographics still apply. Once the orthographic views are completed, then place the pictorial view in an empty location of the drawing area. Try to position the pictorial so that all the drawings look balanced.

Depending on the type of the pictorial drawing inserted, it may need to be scaled down.


Activity 5 - 4


Re-create the following orthographic drawing (2 views) and then create a pictorial drawing to the right or left of the orthographic views. Be sure your orthographic views are complete (all object and hidden lines present). You do not need to dimension anything. The pictorial drawing can be an oblique (cabinet or cavalier) or an isometric. If the pictorial is an isometric, remember to scale it down to 80%.

In addition, create a layout (scale 1:1) with title block.

img13.jpg (59005 bytes)
Units: inches

If you are building an isometric view, you will need to use the technique discussed in the Connecting Isometric Circles section within this unit for portions of the drawing.

img140.jpg (27335 bytes)
isocircles connected using tangent lines


Save the drawing as "pd4" (pictorial drawing) inside your Unit5 folder.