3.1 The Simple Stuff: Ortho, Grid, Tracking, and Snap


3.1 The Simple Stuff: Ortho , Grid, Tracking, and Snap

3.1.1 Ortho

The first drawing aid with which you'll want to familiarize yourself is the Ortho tool. You may recognize the word as an abbreviation of the word Orthographic . We learned about orthographic projections in the first days of drafting class. These present views necessary to describe an item from all sides. Orthographic views include the following (Figure 3.1.1a): front, back, right side, left side, top, and bottom. The views are placed above or below, left or right of a primary view (usually the front) depending on which view it's.

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Figure 3.1.1a:

The Ortho tool restricts drawing or editing movement in a drawing to the left/right or up/down directions. When Ortho is toggled On , your lines will be drawn along the X- or Y-plane. (When drawing in the isometric mode, the X- or Y-planes will be located at 30 ° and 150 °.) This will become clearer during our exercises.

The command sequence for Ortho is

Command: ortho

Enter mode [ON/OFF] <OFF>: on

You can toggle Ortho on or off using the F8 function key or by clicking the Ortho toggle on the status bar.

3.1.2 Grid

One of the drafting tricks we learned back in the pencil days was to lay a background grid sheet on our drawing board before taping down our drawing sheet. This grid served as a lettering guide and helped in aligning different items.

AutoCAD's grid can be quite useful in aligning things. But as we'll see later, it'sn't necessary for sizing text.

The grid toggles On or Off quite easily. And controlling the size and shape of the grid, together with some creative use of the Snap tool, will often dramatically increase your drawing speed.

Controlling the grid size is easy. Following is the command sequence:

Command: grid

Specify grid spacing(X) or [ON/OFF/Snap/ Aspect] <0.5000>: 1

AutoCAD provides some options for the Grid command. The default option sets the grid spacing. In this example, the spacing defaulted to 0.5000 drawing units. We set the spacing to 1 drawing unit. Other options include:

  • ON/OFF : Turns the grid on or off.

  • Snap : Sets the grid spacing equal to the snap increments (we'll look at Snap in a moment).

  • Aspect : Enables you to set a separate spacing for the X- and Y-planes.

you can toggle the grid on or off using the F7 function key or by clicking the Grid toggle on the status bar.

3.1.3 Polar Tracking

A remarkable and intuitive tool, Polar Tracking was designed to assist you by placing a temporary construction line from the last point selected. Additionally, Polar Tracking provides a cheater box detailing distance and angle from the last point selected (Figure 3.1.3a “ next page). This makes it much easier to locate the next point accurately and quickly with a minimal need for absolute, relative, or polar coordinate entry.


Figure 3.1.3a:
Note  

To set your own angles, refer to Section 3.2, "And Now the Easy Way: DSettings ."

Polar Tracking works on the four quadrants (0 °, 90 °, 180 °, and 270 °) by default, but you can set it to track at any angle or to override the settings on the fly. When used with Polar Snap (See Section 3.1.4, "Snap"), you can snap to any point at any angle with little or no need for the keyboard at all!

You can toggle Polar Tracking on or off using the F10 function key or by clicking the Polar toggle on the status bar.

3.1.4 Snap (Polar and Grid)

The grid and Polar Tracking by themselves are only of minimal use, however. So AutoCAD provides a tool that was not available back in the pencil days. The Snap tool actually pulls (or snaps ) the crosshairs to a grid or polar reference. Controlling the snap while referencing the Grid or Polar Tracking construction lines can provide speed to an otherwise tedious job.

Look at the Snap command.

Command: snap

Specify snap spacing or [ON/OFF/Aspect/ Rotate/Style/Type] <0.5000>: [enter the desired spacing or select an option]

Note  

Conventional wisdom suggests that setting the grid snap to half the grid works best for most drawings. This way, you can snap to each grid, and halfway between each. More than a single snap between grids is difficult to follow.

What is the default spacing? Did you say 0.5000 ? Correct. We can see the default inside the <> , as in other commands.

Snap options include:

  • ON/OFF : For turning the snap on or off.

  • Aspect : For setting a different snap spacing horizontally and vertically.

  • Rotate : For rotating the snap when drawing at an angle (see Style )

  • Style : For changing from a standard grid/snap style to an isometric style (we'll look at this in more detail in Section 3.6).

  • Type : For setting either Polar (to snap to points determined with the Auto-Tracking feature) or Grid (to snap to grid referenced points).

Let's try an exercise using Grid , Snap , Polar Tracking , and Ortho .

Note  

Grid , Snap , Polar Tracking , and Ortho would not be of much use if we had to stop a drawing or editing command every time we needed to turn one On or Off . Mercifully, AutoCAD gives us toggles that will work even while we're in the sequence of another command. In other words, we can toggle the Grid , Snap , Polar Tracking , or Ortho On or Off while drawing a line (or doing some other command).

There are two or three ways to toggle each of these items. They are

 

Keyboard

Function Key

Screen

Grid

Ctrl + G

F7

Status bar

Snap

Ctrl + B

F9

Status bar

Ortho

None

F8

Status bar

Polar Tracking

None

F10

Status bar

Object Snap Tracking

None

F11

Status bar

Find the function keys across the top of your keyboard. Identify them by the F followed by a number, such as F8 . Refer to Appendix B for a complete list of AutoCAD's function keys.

Status bar toggles are shown here.

click to expand

To toggle something On or Off at the status bar, place your cursor on the item and click with the left mouse button. A "raised" item is currently Off; an "indented" item is On . To define or redefine the settings of one of these toggles, right-click on it and pick Settings .

Do This: 3.1.4.1 Grid, Snap, Polar Tracking, and Ortho Practice

Try drawing Exercise #1 in Lesson 2 using only the four tools you have just seen.

  1. Start a new drawing using the MyBase2 template you created in Lesson 1 (or you can use Base2.dwt ). It should be in the C:\Steps\Lesson01 folder.

  2. Set the Grid to 1. (You can use the scroll bars to center the grid in the graphics area.)

  3. Set the Snap to ½ and the snap Type to Grid . Be sure Grid and Snap are both toggled On .

  4. Draw the "M" toggling the Ortho On or Off as needed during the drawing.

How much faster did you draw? Usually, at this point, my students begin planning my demise for not having shown them this approach first. I'm really not that cruel . But once these tools are known, it's exceedingly difficult to convince students to learn the Cartesian Coordinate approaches to drawing. As you'll see, both the coordinate system and these drawing tools are quite necessary for speed and accuracy. (Wait until you master OSNAPs!)

Now try drawing the rest of the Lesson 2 exercises using your own settings.




AutoCAD 2004. One Step at a Time (Part 1)
AutoCAD 2004. One Step at a Time (Part 1)
ISBN: N/A
EAN: N/A
Year: 2003
Pages: 162

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