AutoCAD useful notes for engineers and draughtsmen ________

AutoCAD is the most widespread computer aided draughting package currently in use.
I was originally trained in the DOS release 12 version. Since then I have had to use various Windows versions, e.g. LT Release 1 and 2, LT 97, LT 98, Release 13 and 14. Although these versions have many common features they have different locations on the toolbar and it can be a pain finding your way around a different version in a hurry. The following is a short list of some set-up notes that I use as a reminder when jumping between versions. The list is written essentially for R14, LT97 and LT98 but should be usable for R13 and LT release 1 & 2 also.

1. Full Menus and Side Screen Release 13 and 14. If you find that the menu bar does not have the full set of drop down menus you can easily get the full set as follows:
   At the Command Line type MENU and enter. A dialogue box will appear which will allow you to load an acadfull.mnu file. This will typically be found in folder C:\R13\WIN\SUPPORT. It may be necessary to bring up the .mnu extension under the List of Files Type:. Open the acadfull.mnu file. There may be some warning messages given, just accept these. The full set of menus will be loaded and appear on the desktop menu bar.
   
   If you want a side screen menu like the DOS version. From the Tools menu for R14 (Options menu, Preferences..., System, AutoCAD Graphics Window for R13) select Preferences.... A dialogue box will appear. Under Display, check on Screen menu. Click on the OK button.
   
   
2. Auto Save. From the Tools menu for R14, LT97 and LT98 (Options menu R13), (File menu for LT release 1 and 2) select Preferences.... A dialogue box will appear. Under System, Automatic Save, check on the box against Every and set a time to say 60 minutes. Click on the OK button.
   
   
3. English/Metric. From the Options menu for R13 (File menu for LT release 1 and 2) select Preferences.... A dialogue box will appear. Under International, check on the box against English or Metric as required. Click on the OK button.
   
   
4. UCS Icon. If the User Co-ordinate System (UCS) icon is on the screen this can be switched OFF as follows. From the View menu, Display for R14, LT97 and LT98 (Options menu, UCS, Icon for R13), (Assist menu, UCS Icon for LT release 1 and 2) select UCS Icon OFF.
   
   
5. Drawing Aids. From the Tools menu for R14, LT97 and LT98 (Options menu R13), (Settings menu for LT release 1 and 2) select Drawing Aids... A dialogue box will appear. Check OFF: Blips, Quick Text and Groups and also Isometric (if not required). Check ON: Ortho, Solid Fill and Highlight. Set the Snap and Grid to say 5 units. Click on the OK button.
   
   
6. Object Snap. From the Tools menu for R14, LT97 and LT98 (Options menu, Running Object Snap... for R13), (Assist menu, Object Snap... for LT release 1 and 2) select Object Snap Settings... A dialogue box will appear. Select: Running Osnap. Check ON: Intersection and Endpoint. Set the Aperture size using the scroll bar by trial and error. Click on the OK button.
   
   
7. Units. From the Format menu for R14, LT97 and LT98 (Data menu, Units... for R13), (Settings menu, Units Style... for LT release 1 and 2) select Units... A dialogue box will appear. Set ON Decimal and Decimal Degrees. Set the Precision to say 0. Click on the OK button.
   
   
8. Drawing Limits. From the Format menu for R14, LT97 and LT98 (Data menu, Drawing Limits for R13), (Settings menu, Drawing, Limits for LT release 1 and 2) select Drawing Limits... Enter the limits at the Command Line. For say an A3 sheet enter the following: <0,0> and enter <420,297> and enter. Reset the window using Zoom All from the View menu.
   
   Note the standard ISO drawing sheet sizes are as follows:
   A0 --- 1189 x 841
   A1 --- 841 x 594
   A2 --- 594 x 420
   A3 --- 420 x 297
   A4 --- 210 x 297
   
   
9. Associated Dimensions. The AutoCAD default is to have associated dimensions ON. My experience has shown that this can cause potential problems when:
   (a) If drawing details are scaled, the dimensions if present are also scaled.
   (b) If text format tolerances are used, altering one of the tolerances also alters the other tolerances on that layer.
   (c) If a dimension is on a not-to-scale part of a drawing and the dimension is moved the dimension changes to the scaled value.
   Therefore for safety reasons I recommend that the associated dimensions are switched OFF. At the Command Line for R13, R14, LT97 and LT98, (Settings menu, Associative Dimensions for LT release 1 and 2) type DIMASO and enter. Set DIMASO to OFF.
   
   
10. Linetypes. By default a continuous line type on layer '0' will be loaded but you may have to load centre, hidden and phantom line types. Proceed as follows. From the Format menu for R14, LT97 and LT98 (Data menu, Linetype... for R13) select Linetype... A dialogue box will appear. Click on Load... and select CENTER and click OK. Repeat for HIDDEN and PHANTOM line types. For LT release 1 & 2 use (Settings menu, Linetype Style, Load) and enter the line type name e.g. center at the command line.
    
    
11. Linetype Scale. To get the centre and hidden lines to plot properly it is often necessary to adjust the global linetyle scale. The way to do this is to type LTSCALE at the command line and enter. The scale can then be set by trial and error. To set the line type to be the same on Model and Paper Space set PSLTSCALE to 0.
    
    
12. Screen Background Colour. Adjusting the screen background colour can make the drawing easy to read as well as relieving eyestrain. From the Tools menu for R14, LT97 and LT98 (Options menu, Preferences..., System, Color... button for R13), (File menu, Preferences..., Colors... button for LT release 1 and 2) select Preferences... A dialogue box will appear. Select the Color button. A dialogue box will appear. Select Graphics window background from the drop down menu. Select a background colour, a low-key colour like gray or black is usually best. Click on the OK button.
    
    
13. Layers. One of the key features of AutoCAD is the use of layers. By default a continuous line type on layer '0' will be available but to add additional layers e.g. for centre lines and hidden details etc., proceed as follows. From the Format menu for R14, LT97 and LT98 (Data menu, Layers... for R13), (Settings menu, Layer Control... for LT release 1 and 2) select Layer... A dialogue box will appear. Click on the New button and set up the following working layers as a minimum:
    
    

    Layer Name	State	Freeze	Color	Linetype
    DRAW	ON	OFF	WHITE	CONTINUOUS
    CENTRE	ON	OFF	RED	CENTER
    HIDDEN	ON	OFF	YELLOW	HIDDEN
    DIMENSION	ON	OFF	CYAN	CONTINUOUS
    TEXT	ON	OFF	MAGENTA	CONTINUOUS
    HATCH	ON	OFF	GREEN	CONTINUOUS
    GHOST	ON	OFF	BLUE	PHANTOM

    
    These layer names are suggested only and can be altered. The layer colours are selected from those available but should be chosen to contrast with the background colour of the screen, see above.
    
    
14. Text Style. Adjusting the text size and selection of the font is essential to make the drawing easy to read. From the Format menu for R14, LT97 and LT98 (Data menu, Text Style... for R13), (Settings menu, Text Style... for LT release 1 and 2) select Text Style... A dialogue box will appear. Select the style name STANDARD. Select the font name romans.shx (Roman Simplex).
    Set the font Height to 1.0
    Set the effects:
    Upside-down to Off (N)
    Backwards to Off (N)
    Vertical to Off (N)
    Width to 1.0
    Oblique angle to 0
    
    For LT release 1 and 2 the font height and effects have to be set at the command line.
    
    
15. Dimension Style. One of the most time consuming, but essential aspects of producing an engineering drawing is the application of dimensions to the drawing so that it can be read and the information presented in a clear and unambiguous manner. The dimension style allows the font family, geometry, format and annotation of the dimensions to be set. From the Format menu for R14, LT97 and LT98 (Data menu, Dimension Style... for R13), (Settings menu, Dimension Style... for LT release 1 and 2) select Dimension Style... A dialogue box will appear. Set up the following:
    
    Select the style name STANDARD.
    Family. Select the Parent option button.
    
    Click on the Geometry... button. A dialogue box will appear.
    Set Dimension line, spacing to 4, do not suppress the lines
    Set Extension line, extension to 1.25 and Origin Offset to 2.5, do not suppress the lines.
    Set Arrow heads to 1st closed filled and 2nd closed filled and Size 3
    Set Centre mark to None.
    Set Scale, overall scale to 1 (you can use this overall scale to adjust the dimension size by trial and error on an actual print of the drawing).
    Click on the OK button.
    
    Click on the Format... button. A dialogue box will appear.
    Set Force lines inside to On (tick).
    Set Fit to Best fit.
    Set Horizontal justification to Centered.
    Set Vertical justification to Above.
    Set Text Inside and Outside Horizontal to Off (de-select tick).
    Click on the OK button.
    
    Click on the Annotation... button. A dialogue box will appear.
    Set Primary units. Click on Units... button. Set Units to Decimal and Angle to Decimal Degrees. Set Dimensions Precision to say 0.0 and Tolerance Precision to say 0.0 Set Scale Linear to 1.0
    Set Tolerance Method to None.
    Set Text Style to STANDARD.
    Set Text Height to 3.
    Set Text Gap to 1.25.
    Click on the OK button.
    
    For LT release 1 and 2 the dialog boxes have a slightly different arrangement but most of the above can be set.
    
    
16. Mirror Text. It is often necessary to mirror drawing objects. If text is to be mirrored it is necessary to set MIRRTEXT to 0 to avoid the text being mirrored. Proceed as follows. At the command line type MIRRTEXT and enter. Set MIRRTEXT to 0.
    
    
17. Distance/List. It is often necessary to get a distance or a listing of a drawing object. Proceed as follows. From the Tools menu for R14, LT97 and LT98 (Edit menu, Inquiry for R13), (Assist menu for LT release 1 and 2). Select Inquiry, Distance or List will allow the distance or listing to be obtained.
    
    
18. Offset. One of the most useful commands is to set an offset distance. Proceed as follows. From the Modify menu for R14, LT97 and LT98 (Construct menu, Offset for R13, LT release 1 and 2). Select Offset will allow the offset distance to be set at the command line.
    
    
19. Purg. To reduce the size of the drawing file saved to disk it is necessary to purg the drawing of unused objects. From the File menu for R14, LT97 and LT98 (Data menu, Purg for R13), (Modify menu, Purg for LT release 1 and 2) select Drawing Aids... Under Drawing Utilities, Purg... will allow the drawing to be purged of unwanted objects.
    
    
20. Attributes. The use of attributes can have advantages where repetitive text is to be input like in a company standard border sheet. The following notes show the procedure for creating and editing attributes.
    
    Create Attribute. From the Draw menu (Construct menu for LT release 2 and R13).
    Select Block, Define Attribute.... Enter the required attribute text in Tag, Prompt and Value.
    e.g. For Tag enter: Your_Name [Note no spaces allowed].
    For Prompt enter: Enter Your Name
    For Value enter a default: Andrew C. Whyte.
    Now select the Pick Point button and position where the attribute text is to be inserted. Click the OK button to store the attribute.
    
    Attaching an Attribute to a Block. Before an attribute can be activated it must be attached to a block. Proceed as follows: from the Draw menu (Construct menu for LT release 2). Select Block, Make.... A create block dialog box will appear. Give the block a name. Then use the Select Objects button to select the items including the attributes to make up the block. Note that the order in which you select the attributes determines the order of Prompt when you insert the block.
    
    Editing Attribute Definitions.
    (1) Prior to attaching an attribute to a block, it is possible to edit the attribute as follows: from the Modify menu. Select Object, Text.... A dialog box will allow you to alter the Tag, Prompt and Value of the attribute.
    (2) If the attribute has already been attached to a block you must proceed as follows: from the Modify menu. Select Object, Attribute, Single or Global.
    Selecting Single presents a dialog box that will allow the text of each attribute to be edited.
    Selecting Global allows specific attribute text parameters, e.g. Position, Height, Angle, etc. to be altered at the command line.
    
    
21. Paper Space. A 2D AutoCAD drawing can be produced entirely in Model Space (and many companies are happy to work with their drawings set up entirely in Model Space). However some companies prefer to work using their title border sheet in Paper Space. The following procedure can be used to set up the border sheet in Paper Space.
    
    1. Prepare the drawing as normal in Model Space.
    2. Add layers for the border sheet and a viewport. Say layers BORDER and VPORT.
    3. Make VPORT the current layer.
    4. Enter Paper Space.
    5. From the View menu enter Floating Viewports and select 1 Viewport. You now enter the size of the viewport. e.g. for say A3 size, at the command line: first point, enter 0,0 for other corner, enter 420,297
    6. Do a Zoom All.
    7. Enter Floating Model Space.
    8. Enter Z for Zoom at the command line followed by S for Scale (or select Zoom and Scale from the View drop down menu). You now require to enter the correct scale factor for the paper space. e.g. for say a half scale, at the command prompt Scale(X/XP) enter 0.5xp and return.
    9. Position the drawing, if necessary, in the viewport using the Move or Pan command, in Model Space.
    10. Enter Paper Space and make BORDER the current layer.
    11. Insert the border sheet. Use Insertion point: 0,0 at the command prompt and scale of 1.
    12. Enter Floating Model space and finally position the drawing if necessary.
    13. Freeze the VPORT layer to remove the viewport edge prior to saving and printing.
    14. Save the drawing.
    
    Important Note. The drawing cannot be altered in Paper Space. To make alterations it is necessary to enter Tiled Model Space. It will be necessary to flip between Model and Paper Space to view the effect of the changes. When viewing details of the drawing using the zoom command, it is best to avoid Floating Model space. Enter Paper Space or Tiled Model Space first then zoom.
    
    
22. Isometric Drawing. From the Tools menu for R14, LT97 and LT98 (Options menu, Drawing Aids... for R13), (Settings menu, Drawing Aids... for LT release 1 and 2) select Drawing Aids... click on Isometric Snap/Grid. Click on the OK button. The Isoplanes cross-hairs can be toggled Top, Left and Right by the two keys Ctrl and E or by the F5 key.
    
    Note. Although it is common practice to draw the isometric drawing to a scale of 100%, the true isometric view has the axis distances shortened in the ratio of 0.816:1
    
    
23. 3D Drawing. The following are a few set-up notes based on Release 13.
    
    UCS Icon. Switch On from Options menu, UCS, Icon.
    UCS Icon Origin. Activate from Options menu, UCS, Icon, Origin.
    UCS Icon Follow. Activate from Options menu, UCS, Icon, Follow.
    View Ports. It is convenient to work with more than one view port. Type VPORTS at the command line for a choice of view ports. Alternatively from the View menu, Tiled Viewports. 3 viewports and right is a good choice to start with.
    UCS Presets. Activate from the View menu, Preset UCS... A dialogue box will appear with directions of viewing.
    View Points Presets. Activate from the View menu, 3D Viewpoint Presets. A drop down menu will appear with a selection of viewing presets.
    View Points Setting. It is often convenient to set the view point for each viewport individually as follows. Click on a viewport. Activate the View drop down menu and select 3D Viewpoint. A drop down menu will appear, select Rotate... A dialogue box will appear that will allow you to set the X axis and XY plane angles. Suggested angles are:
    
    

    Viewport	X Axis	XY plane
    Right	315 degrees	30 degrees
    Top Left	270 degrees	0 degrees
    Bottom Left	270 degrees	90 degrees

    
    Method of Drawing. Using the solids tool is one convenient way of producing a 3D model. Activate the Draw menu and select Solids. A drop down menu will appear with a selection of solid objects. The drawing objects can be moved, rotated, mirrored and arrayed etc., by activating the Modify or Construct drop down menus.