Computer Aided Draughting 417
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d:\N-Design\Des21-1.pm5
150°
30°
To pLeft
Right90°
(refer Chapter 2 and section 2.6) and the sectioned zone in any view is shown by cross-hatched
lines. Thin lines represent the cross-hatched lines. It is possible to change the hatching lines.
SOL VIEW uses orthographic projections with floating paper space view ports to layout
multi-and sectional view drawings of 3D solids.
Command: SOLVIEW
UCS/ ORTHO/ AUXILIARY / SECTION/ :
By choosing the option section-use the original view port and specify two points at the
prompts to define the section plane. Then define the viewing side by specifying a point on one
side of the cutting plane, for the next prompt.
21.15 ISOMETRIC DRAWING
The command “isoplane” permits to switch the cursor orientation between the left, top and
right isometric planes when the snap mode is set to the isometric style.
Command: ISOPLANE
Left /top/ right/ : enter the choice to move to right, isoplane left or isoplane top.
By pressing ctrl and E keys simultaneously, toggle takes place between the isometric planes.
21.15.1 Setting Isometric Grid and Snap
Use snap command for choosing between the
standard orthogonal snap style and isometric snap
style-by selecting style. The grid points are arranged
along 30°, 90° and 150° lines. The distance between
the grid lines is determined by the vertical spacing.
To draw the cube in isometric view
(Fig. 21.18):
Command: isoplane-by choosing top, left and
right planes, one at a time, the squares are drawn to
complete the cube. Isometric circles are drawn using
the command ellipse and selecting iso-circles option.
This is possible when isometric snap is on.
21.16 BASIC DIMENSIONING
In many applications, a drawing should contain annotations showing lengths or distances or
angles between objects to convey the desired information. Dimensioning is the process of adding
these annotations to a drawing. AutoCAD provides four basic types of dimensioning; linear,
angular, diameter and radius.
DIM and DIMI Commands—DIMI command allows executing one dimensioning command
and then returns to the normal command mode. If several dimensioning commands are to be
executed, DIM command should be used. In this mode, the normal set of AutoCAD commands
is replaced by a special set of dimensioning commands. To end the process of dimensioning,
EXIT command has to be used.
The dimensioning commands can be grouped into six categories:
1. Linear — is done with a horizontal, vertical, aligned and rotated command.
However, rotated command requires specifying the dimension line
angle explicitly.
Fig. 21.18