AutoCAD

Work with Linetypes

2010-08-10T00:27:00.000-07:00

A linetype is a repeating pattern of dashes, dots, and blank spaces displayed in a line or a curve. You assign linetypes to objects either by layer or by specifying the linetype explicitly, independent of layers.
In addition to choosing a linetype, you can set its scale to control the size of the dashes and spaces, and you can create your own custom linetypes.

At the start of a project, you load the linetypes that are required for the project so that they are available when you need them. If you want to know what linetypes are already available, you can display a list of linetypes that are loaded in the drawing or stored in an LIN (linetype definition) file.
AutoCAD includes the linetype definition files acad.lin and acadiso.lin. Which linetype file is appropriate depends on whether you use imperial or metric measurements.
• For imperial units, use the acad.lin file.
• For metric measurements, use the acadiso.lin file.
Both linetype definition files contain several complex linetypes.
If you select a linetype whose name begins with ACAD_ISO, you can use the ISO pen-width option when you plot.
You can remove unreferenced linetype information with PURGE or by deleting the linetype from the Linetype Manager. BYBLOCK, BYLAYER, and CONTINUOUS linetypes cannot be removed
(fr.autocad.help)

Create Fillets

2010-08-08T01:47:00.000-07:00

Filleting connects two objects with a smoothly fitted arc of a specified radius. An inside corner is called a fillet and an outside corner is called a round; you can create both using FILLET in AutoCAD.

You can fillet
Arcs
Circles
Ellipses and elliptical arcs
Lines
Polylines
Rays
Splines
Xlines
Using FILLET is also a convenient method of creating an arc with a specified radius that is tangent to two selected objects. FILLET can be used to round all corners on a polyline using a single command.

If both objects being filleted are on the same layer, the fillet arc is created on that layer. Otherwise, the fillet arc is created on the current layer. The layer affects object properties including color and linetype.

Use the Multiple option to fillet more than one set of objects without leaving the command.

Set the Fillet Radius
The fillet radius is the radius of the arc that connects filleted objects. Changing the fillet radius affects subsequent fillets. If you set the fillet radius to 0, filleted objects are trimmed or extended until they intersect, but no arc is created.

Trim and Extend Filleted Objects
You can use the Trim option to specify whether the selected objects are trimmed or extended to the endpoints of the resulting arc or left unchanged. By default, all objects except circles, full ellipses, closed polylines, and splines are trimmed or extended when filleted.

Control the Location of the Fillet
Depending on the locations you specify, more than one possible fillet can exist between the selected objects. Compare the selection points and resulting fillets in the illustrations.

Fillet Line and Polyline Combinations
For you to fillet line and polyline combinations, the line or its extension must intersect one of the polyline line segments. If the Trim option is on, the filleted objects and the fillet arc join to form a single new polyline.

Fillet an Entire Polyline
You can fillet an entire polyline or remove fillets from an entire polyline.

If you set a nonzero fillet radius, AutoCAD inserts fillet arcs at the vertex of each polyline segment that is long enough to accommodate the fillet radius.

If two polyline line segments converge as they approach an arc segment that separates them, AutoCAD removes the arc segment and replaces it with a fillet arc.

If you set the fillet radius to 0, no fillet arcs are inserted. If two polyline line segments are separated by one arc segment, AutoCAD removes that arc and extends the lines until they intersect.

Fillet Parallel Lines
You can fillet parallel lines, xlines, and rays. AutoCAD ignores the current fillet radius and creates an arc that is tangent to both parallel objects and located in the plane common to both objects.

The first selected object must be a line or a ray, but the second object can be a line, an xline, or a ray. The fillet arc connects as shown in the illustration.

Fillet in 3D
You can fillet coplanar objects with extrusion directions not parallel to the Z axis of the current UCS. AutoCAD determines the extrusion direction for the fillet arc in 3D space as follows.

For objects on the same plane with the same extrusion direction normal to that plane, the fillet arc is on that plane and has the same extrusion direction.

If the objects are on the same plane but have opposite or different extrusion directions, the fillet arc is placed on that object plane with an extrusion direction normal to the object plane and inclined towards the positive Z direction of the current UCS. For example, suppose two arcs, A and B, are on the same plane in 3D space but have opposite extrusion directions (0,0.5,0.8) and (0,–0.5,–0.8) relative to the current UCS. The fillet arc adopts the extrusion direction (0,0.5,0.8).
(fr.autocad.help)

create a line

2010-08-07T01:24:00.000-07:00

With LINE, you can create a series of contiguous line segments.
Each single line segment can be edited separately from the other line segments in a series. You can close a sequence of line segments so that the first and last segments are joined.
You can assign properties to lines including color, linetype, and lineweight. For more information about properties, see Control the Properties of Objects.
You specify the locations that define the endpoints of each line with precision. You can
Enter the coordinate values for an endpoint, using either absolute or relative coordinates
Specify an object snap relative to an existing object. For example, you can specify the center of a circle as one endpoint of the line
Turn grid snap on and snap to a location
There are other methods for creating precise lines. A highly efficient technique is to offset a line from an existing line, and then trim or extend it to the desired length.
Use polyline objects instead of line objects if you want the segments to be connected as a single object.

To draw lines
On the Draw menu, click Line.
Specify the start point.
You can use the pointing device or enter coordinate values on the command line.
Complete the first line segment by specifying the endpoint.
To undo the previous line segment during the LINE command, enter u or click Undo on the toolbar.
Specify the endpoints of any additional line segments.
Press ENTER to end or c to close a series of line segments.
To start a new line at the endpoint of the last line drawn, start the LINE command again and press ENTER at the Specify Start Point prompt.
(fr.autocad.help)

offset

2010-08-06T01:04:00.000-07:00

Offsetting creates a new object whose shape parallels the shape of a selected object. Offsetting a circle or an arc creates a larger or smaller circle or arc, depending on which side you specify for the offset.
A highly effective drawing technique is to offset objects and then trim or extend their ends.
2D polylines and splines are trimmed automatically when the offset distance is larger than can otherwise be accommodated.

You can offset
Lines
Arcs
Circles
Ellipses and elliptical arcs (resulting in an oval-shaped spline)
2D polylines
Construction lines (xlines) and rays
Splines

To offset an object by specifying a distance
From the Modify menu, choose Offset.
Specify the offset distance.
You can enter a value or use the pointing device.

Select the object to offset.
Specify a point on the side where you want to place the new objects.
Select another object to offset, or press ENTER to end the command.

To offset an object through a point

From the Modify menu, choose Offset.
Enter t (Through).
Select the object to offset.
Specify the through point.
Select another object to offset, or press ENTER to end the command.
(fr.autocad.help)

Drawing Objects

2010-08-05T07:10:00.000-07:00

A slide is a snapshot of a drawing. Although it contains a picture of the drawing at a given instant, it is not a drawing file. You cannot import a slide file into the current drawing, nor can you edit or print a slide. You can only view it.

You can use slide files in the following ways:
For making presentations within AutoCAD®
For viewing a snapshot of a drawing while working on a different drawing
For creating menus of image tiles within a dialog box
You create a slide by saving the current view in slide format. A slide created in model space shows only the current viewport. A slide created in paper space shows all visible viewports and their contents. Slides show only what was visible. They do not show objects on layers that were turned off or frozen or objects in viewports that were turned off.

When you view a slide file, it temporarily replaces objects on the screen. You can draw on top of it, but when you change the view (by redrawing, panning, or zooming), the slide file disappears, and AutoCAD redisplays only what you drew and any preexisting objects.

You can display slides one by one or use a script to display slides in sequence. Slides also can be used in custom menus. For example, if you create scripts that insert blocks containing mechanical parts you use frequently, you can design a custom image tile menu that displays a slide of each part. When you click the slide image on the menu, AutoCAD inserts the block into the drawing.

A slide library is a file containing one or more slides. Slide library files are used for creating custom image tile menus and for combining several slide files for convenient file management.

You cannot edit a slide. You must change the original drawing and remake the slide. If you use a low-resolution graphics monitor when creating a slide file and later upgrade to a high-resolution monitor, you can still view the slide. AutoCAD adjusts the image accordingly; however, the slide does not take full advantage of the new monitor until you remake the slide file from the original drawing.
fr.AutoCAD.help

Save a Drawing

2010-08-04T06:46:00.000-07:00

You save drawing files for later use just as you do with other Microsoft Windows applications. AutoCAD also provides automatic saving, backup files, and other options for saving.

When you are working on a drawing, you should save it frequently. Saving protects you from losing work in the event of a power failure or other unexpected event. If you want to create a new version of a drawing without affecting the original drawing, you can save it under another name.

The file extension for AutoCAD drawing files is .dwg, and unless you change the default file format in which drawings are saved, drawings are saved in the latest drawing-file format. This format is optimized for file compression and for use on a network.

Save Your Drawing Automatically
If you turn on the automatic saving option, your drawing is saved at specified time intervals. By default, files saved automatically are temporarily assigned the name filename_a_b_nnnn.sv$. Filename is the current drawing name, a is the number of open instances of the same drawing file in the same AutoCAD session, b is the number of open instances of the same drawing in different sessions of AutoCAD, and nnnn is a random number generated by AutoCAD.

These temporary files are automatically deleted when a drawing closes normally. However, the files remain in the event of a program failure or a power failure. To recover a previous version of your drawing from the automatically saved file, rename the file using a .dwg extension in place of the .sv$ extension.

Use Backup Files
If you turn on automatic backups, AutoCAD saves the previous version of your drawing files to a file with the same name and a .bak file extension. To recover the previous version of your drawing from a backup file, rename the file using a .dwg extension.

Save Part of a Drawing File
If you want to create a new drawing file from part of an existing drawing, you can use BLOCK or WBLOCK. With either command, you can select objects or specify a block definition in your current drawing and save them in a new drawing file. You can also save a description along with the new drawing.

Save to a Different Type of Drawing File
You can save a drawing to an earlier version of the drawing format (DWG) or drawing interchange format (DXF), or save a drawing as a template file. Choose the format from Files of Type in the Save Drawing As dialog box.

Reduce the Time Required to Save a Drawing File
You can reduce the time required to save a drawing file if you specify incremental saves rather than full saves. An incremental save updates only those portions of the saved drawing file that you changed.

When you use incremental saves, drawing files will contain a percentage of potentially wasted space. This percentage increases after each incremental save until it reaches a specified maximum, at which time a full save is performed instead. You can set the incremental save percentage in the Open and Save tab of the Options dialog box or by setting the value of the system variable ISAVEPERCENT. If you set the value of ISAVEPERCENT to 0, all saves are full saves.

To reduce the size of drawing files, it is recommended that you perform a full save (with IPERCENTSAVE set to 0) before transmitting or archiving a drawing.

Avoid File Name Issues for International Work
If you share drawing files with companies in other countries and regions, the drawing file names might contain characters that are not available in other languages.

For example, a drawing file created in China might be saved with double-byte characters in the file name. When this drawing file is transmitted to a different language version of Windows, either of the following will occur:

If you do not have Asian language support turned on, the file name characters appear as a series of question marks in Windows Explorer
If you do have Asian language support turned on, the file name characters are visible in Windows Explorer
In either case, you will not be able to open the drawing file in AutoCAD LT unless you rename it. This is also true for special characters in file names of European and other languages.

To avoid these issues when your language uses double-byte characters or special characters, do not use high ASCII values (values of 80 hexadecimal and above) when choosing a file name.

To save a drawing

On the File menu, click Save.
If you previously saved and named the drawing, AutoCAD saves any changes and redisplays the Command prompt. If you have never saved the drawing, the Save Drawing As dialog box is displayed.

In the Save Drawing As dialog box under File Name, enter the new drawing name; the file extension is not required. Then click Save.
(fr.AutoCAD.help)

Layer command

2010-08-03T23:43:00.000-07:00

Layers are the equivalent of the overlays used in paper-based drafting. Layers are the primary organizational tool in AutoCAD®: you use them to group information by function and to enforce linetype, color, and other standards.
By creating layers, you can associate similar types of objects by assigning them to the same layer. For example, you can put construction lines, text, dimensions, and title blocks on separate layers. You can then control
Whether objects on a layer are visible in any viewports
Whether and how objects are plotted
What color is assigned to all objects on a layer
What default linetype and lineweight are assigned to all objects on a layer
Whether objects on a layer can be modified
Every drawing includes a layer named 0. Layer 0 cannot be deleted or renamed. It has two purposes:
Ensure that every drawing includes at least one layer
Provide a special layer that relates to controlling colors in blocks
Note It is recommended that you create several new layers with which to organize your drawing rather than create your entire drawing on layer 0.
(fr.autocad.help)

begin a new drawing

2010-08-02T01:10:00.000-07:00

A quick way to begin a new drawing is to start from scratch, which starts a drawing that uses settings from a default drawing template file.

You can start from scratch from the Create New Drawing dialog box, from the Select Template dialog box, or without using a dialog box at all. In each case, you use either the NEW command or the QNEW command.

Use the Create New Drawing Dialog Box
The Create New Drawing dialog box is displayed under the following conditions:

You set the STARTUP system variable to 1 (on).
You set the FILEDIA system variable to 1 (on).
You click New on the File menu or Qnew on the Standard toolbar when no drawing template file is specified in the Options dialog box.
The Create New Drawing dialog box provides several methods for starting a new drawing.

When you use Start from Scratch, you can specify either imperial or metric units for the new drawing. The setting you select determines default values used for many system variables controlling text, dimensions, grid, snap, and the default linetype and hatch pattern file.

Imperial. Creates a new drawing based on the imperial measurement system. The drawing uses internal default values, and the default grid display boundary, called the grid limits, is 12 × 9 inches.
Metric. Creates a new drawing based on the metric measurement system. The drawing uses internal default values, and the default grid display boundary is 429 × 297 millimeters.
Use the Select Template Dialog Box
The Select Template dialog box is displayed under the following conditions:

You set the STARTUP system variable to 0 (off).
You set the FILEDIA system variable to 1 (on).
You click New on the File menu or, by default, Qnew on the Standard toobar.
At the bottom-right corner of the Select Template dialog box, there is an Open button with an arrow button next to it. If you click the arrow button, you can choose between two internal default drawing templates, metric or imperial.

Use a Default Drawing Template File
The fastest way to begin working on a new drawing is to start automatically with a default drawing template file. No dialog box is displayed with this method:

You set the STARTUP system variable to 0 (off).
You set the FILEDIA system variable to 1 (on).
You specify a default drawing template file in the Options dialog box on the Files tab. Click the node labeled "Drawing Template Settings" and specify a path and drawing template file.
You click Qnew on the Standard toolbar.
From now on, a new drawing is immediately created that is based on the specified default drawing template file.
If no template file is specified in the Options dialog box, QNEW displays the Select Template dialog box.
To start a drawing from scratch with the Create Drawing dialog box
If necessary, set the STARTUP system variable to 1 and the FILEDIA system variable to 1. On the command line, enter startup and 1; then enter filedia and 1.
On the File menu, click New.
In the Create New Drawing dialog box, click Start from Scratch.
Under Default Settings, click either Imperial or Metric.
(fr.autocad.help)

Opening Drawings

2010-08-01T06:55:00.000-07:00

To open an existing AutoCAD drawing, you can use Open on the File menu to display the Select File dialog box.

You can also open drawings by dragging them from Windows Explorer into AutoCAD. If you drop one or more drawings anywhere outside the drawing area—for example, the command line or the blank space next to the toolbars—AutoCAD opens the drawings. However, if you drag a single drawing into the drawing area of an open drawing, the new drawing is not opened but inserted as a block reference.

You can double-click a drawing in Windows Explorer to launch AutoCAD and open the drawing. If AutoCAD is already running, the drawing opens in the current session rather than in a second session.

If you organize drawings using the sheet set feature, you can use the Sheet Set Manager to locate and open the drawings in the sheet set.

Check Drawing Authenticity
If the DWGCHECK system variable is set to On (1), AutoCAD checks the DWG file format and displays an alert box if

The drawing file format is AutoCAD LT 97 or later or AutoCAD Release 14 or later and
The file was last saved by a program other than AutoCAD LT 97 or later or AutoCAD Release 14 or later
To avoid checking for file authenticity each time you open drawings, clear the Always Show This Dialog Box option when the alert is displayed. Alternatively, you can set DWGCHECK to Off (0).

Change the Default Drawing Folder
Each time you start AutoCAD, the last used paths in each particular standard file selection dialog box are maintained across AutoCAD sessions. Alternatively, you can configure AutoCAD to default always to a particular path by changing the default drawing folder.

To open an existing drawing

From the File menu, choose Open.
In the Select File dialog box, select one or more files and choose Open.
The icons on the left side of the dialog box provide quick access to commonly used files and file locations. To reorder the icons, drag them to a new location. To add, modify, or remove an icon, right-click the icon to display a shortcut menu.
(fr. AutoCAD.help)

Tool palettes

2009-11-06T09:38:00.000-08:00

sorry, out of service

Start a Drawing

2009-07-27T06:36:00.000-07:00

sorry, out of service