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# Steps to Draw an Isometric View

Rural Technology

• Orientation of the object and point of Origin, these two things are to be decided before drawing the Isometric View. For every Isometric View a separate Scale is required to be drawn.
• Draw the Isometric and Natural scale, mark each dimension on the Natural scale, drop a perpendicular on the horizontal line, and transfer the corresponding Isometric dimension on the paper with the help of divider. (As Isometric dimension cannot be and need not be measured in cm or inches). Suppose we need a dimension of say, 35 mm to be converted into Isometric Scale. Take 35 mm dimension on the Natural scale, drop a perpendicular on the horizontal line. The perpendicular meets the 30° line at point A. The dimension OA is the Isometric dimension of Natural 35 mm. Transfer the dimension OA to the Isometric View to be drawn.
• Take an Origin ‘O’ on the paper ref fig. 11.12, with sufficient space to draw the Isometric above the point ‘O’. Draw a horizontal line XY through ‘O’ and another vertical line OZ.

• Referring the orthographic Views, transfer the height, length and width of the object on the Natural Scale and convert them into Isometric Scale.
• With the help of a Divider, transfer the height on the vertical line OZ, the length along OX and width along OY. Consider the Origin ‘O’in the Elevation of the Orthographic Views (Lesson 2) to be the Origin in the Isometric View here.

• Complete the entire Isometric block with the help of Tee Square and 30-60 Set Square.

### Examples of drawing isometric drawing

#### 1) Draw isometric drawing of a cube.

Orthographic projection of cube of 40cm length, 40cm height and 40cm width is shown below.

To draw isometric of cube

1) Draw two basic 30 degree guidelines, one to the left and one to the right, plus a vertical guideline in the centre of the drawing. In this example three edges of the cube have been drawn over the guidelines (they are slightly darker) 2) Remember to draw the line of length equal to isometric scale. Therefore each side of 40cm cube should be converted to isometric scale. Complete the top of the cube by projecting lines with the 30 degree set square as shown.

#### 2) Draw a square in isometric Square ABCD is of 50mm size.

1) Draw a horizontal line. 2) Mark one corner of square at the center of line ‘D’ in fig.17 3) Draw two lines as shown in the fig at 30° to the horizontal line. 4) Select isometric scale as shown in the previous example. Measure distance on isometric scale. 5) Draw point A and B equal to isometric length. 6) Mark point ‘C’ using compass of length of isometric scale.

#### 3) Draw an isometric circle

Draw a square ABCD, centred on the position of the hole. The square should be the same size as the diameter of the hole. Draw curves ( GF and HE ) using compass as shown in the fig. Center of line CD and AB are marked as G and E. Join AG and CE as shown in the figure. Draw arc EF and GH using compass as shown in the figure. The isometric of circle is ellipse.

1. Stool

### What you have learnt

In this chapter, you read the orthographic and isometric projection. You learnt to draw orthographic and isometric projection. You learnt the procedure to draw them. You learnt to draw basic isometric shapes. You also learnt to present textual information to drawing form and to read information on drawing and write in textual form.

## Terminal Questions

1. Convert textual information into graphical form - A box measures 30 mm (length) ´ 20 mm (breadth) ´ 45 mm (height). Draw its isometric sketch with length on your right side. 2. Convert textual information into graphical form - A cylinder measures 25 mm (base diameter) ´ 75 mm (height). Draw its three orthographic views. 3. Convert graphical information into textual form

a. What is the total length and breadth of the object?

b. State the dimensions of the top of the object.

c. What is the total length of each of the 4 legs?

d. What is the maximum distance between two legs?

e. What are the M.S. Angle dimensions?

f. Which two materials are suggested for the top?

### suggested activity

Make a orthographic projection of your house.

Rural Technology