Datasheet

Use From, Auto Tracking, or @ to Begin Drawing
If you know that you need to start drawing an object a specific distance from an existing
object, use the From osnap and the @ symbol. For example, if you want to start a rectangle
10 units over and 45 units up from an existing endpoint, do the following:
1. Start the RECTANG command.
2. Use the From osnap.
3. Select the starting point.
4. Type the coordinates for the first corner of the rectangle as @10,45.
If you have POLAR, OSNAP, and OTRACK on, and the
Extension osnap is set as a running osnap, you can pause over
any running osnap, acquire a temporary tracking vector, and use
it with direct-distance entry to quickly draw an object relative to
another object. See Figure 1.12.
Even better, play with the Temporary Track Point osnap until
you understand how to use it, because it allows you to chase points
all over the screen by typing TT prior to acquiring a tracking point.
The new tracking point is temporary until you actually select it. I
use TT a lot, and if you haven’t figured it out, it’s worth trying.
Using CIRCLE and FILLET to Create Tangent Arcs
Another common shape involves tangent arcs. The quickest way to create an inside
(concave) arc between two circles is to use the FILLET command with the proper radius
set. However, an outside (convex) arc can’t be drawn between two circles or arcs using
FILLET. You must use the CIRCLE command with the TTR option and trim out the
unwanted portion of the circle. The location of your cursor on the circles when you select
tangent points determines whether a concave or a convex arc result. (See the Deferred
Tangent tooltip in Figure 1.13.)
The @ symbol can be used by itself to select the last point you entered.
You can change the default direction of angles from counterclockwise to clockwise to do this
kind of drawing when it’s easier to draw clockwise. But if you change the angular direction
from counterclockwise to clockwise to simplify drawing a single shape, make sure you
change it back to avoid confusion later.
20 ■ chapter 1: AutoCAD Productivity
Figure 1.12
Hover over an osnap
to acquire a point
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