utoCAD Tutorial 6:
F
OR RELEASE 2000i


PLEASE READ: ___________

    These tutorials were designed to be part of the introductory courses taught by the Graphic Communications Program at NORTH CAROLINA STATE UNIVERSITY. All of the directions used in this, and the other tutorials in this series, assume that you are running AutoCAD Release 2000i. These directions will only work with Release 2000i. Other versions may not have the same commands or format.


OBJECTIVES:

After completing this tutorial:

  1. you will be able to add horizontal, vertical, diameter, and radius dimensions to a multiview drawing in AutoCAD;

  2. create continue and baseline dimensions;

  3. create a dimensioning style; and

  4. use the Mtext option under the Dimension commands to create counterbore and countersink dimensions.


STEP 1

    Now that you have completed a number of drawings in AutoCAD, it is time to learn how to dimension them. You will receive less help in this tutorial since by now you should be able to follow AutoCAD's prompts with little difficulty.

For this tutorial, you will again use a file I created and copy it onto your harddrive or a floppy disk. To access this file, click on the DIM30 file link.
DIM30

After selecting the DIM30 link, one of two things could happen:

  1. the AutoCAD program will launch and open the file,

    OR

  2. a dialogue box will appear.
    If the dialogue box appears, use the appropriate selections to save the file to your harddrive or a floppy disk.

  3. Once it is saved to either of these devices, open your classtemplate file, change to Model Space, and use the BLOCK option under the INSERT menu, to insert the model in the DIM30 file into the classtemplate file.

  4. Next, use Save as... to rename the file, tutor6.

  5. With model inserted, explode the model ONCE so that it can be edited and change your the VPOINT to 300 degrees on the XY plane and 35 degrees to the XY plane. The model should look like the illustration in FIGURE 1.

    NOTE: If you explode it more than once, Solview and Soldraw will not work and parts of the model will seem to have disappeared.

FIGURE 1


STEP 2

    You will begin this tutorial by using Solview and Soldraw to create a 2D Multiview Drawing from the model, so you will need to complete the following:

  1. Change to Layout1, and check the UCS in Layout1. If it displays a broken pencil icon, use the UCS command and the View under the UCS's New option to change the the UCS to match Layout1.

  2. Use the Solview command to create a front, side and top view. Use a SCALE value of .5. Leave enough space around your views so you can add dimensions. Your viewports should be close to each other, but fairly large. Look at FIGURE 2 for an estimation of their proper sizes.

    NOTES:

    To increase the size of a floating viewport, switch or check to see if you are in the PAPER side of Paper Space. Click on the edge of the viewport to display the corner handles. Click on a corner handle, so that it turns RED, and drag the corner to a new location.

    To move a floating viewport, switch to the PAPER side of Paper Space, TURN on ORTHO to constrain the direction the viewport can move and use the Move command to reposition the viewport. Turn off ORTHO when done.

    To rescale views if they no long match, switch to the MODEL side of Paper Space and use Zoom XP in each viewport. Remember you must scale the view the same amount that you scaled the view when you used Solview.

    To check alignment of the views, change to the PAPER side of Paper Space and draw a line that connects one element in a view to the same feature in an adjacent view that it should line up with. If they are properly aligned, the line will be straight.

    To realign views that are out of alignment, switch to the MODEL side of Paper Space and use Mvsetup to realign the views. NOTE: You should use Zoom XP before you align the views. Most likely the reason that they are no longer aligned is that you Zoomed in the Model side of Paper Space.


  3. Now, use the Soldraw command to extract the two-dimensional multiviews.

  4. Add a Front-CEN, Top-CEN, and Side-CEN Layer , change their color assignment and line type to Center so you can add center lines.

  5. While in the Layer dialogue box, check the colors of the -DIM layers, -HID layers, and -VIS layers. Change the -VIS layers Lineweight to .7.

  6. Add center lines where needed (see FIGURE 2). The diameter for each hole is listed below.

    The diameter of the small hole associated with the Countersink is 26.
    The diameter of the Countersink is 40.
    The diameter of the small hole associated with the Counterbore is 20.
    The diameter of the Counterbore is 40.

     REMINDER: you should be in the MODEL side of Paper Space to add the center lines.


    You must be in the
    -CEN layer when you add your center lines.
    You can use the
    Offset, Extend, and the Layer Status Bar (to change lines to a different layer) to place the center lines.


  7.  Use the Vplayer command to FREEZE the appropriate layers in each viewport so the center lines that should not be displayed are removed. HINT: While in the Top Viewport, for instance, you would Freeze the Front-CEN and Side-CEN layers. You freeze the -CEN layers for the viewports that are not active when you use the Vplayer command.

If you need to review these procedures in more detail, look at TUTORIAL 4 again.

The drawing should look like FIGURE 2 when the steps, listed above, are completed.

FIGURE 2


STEP 3

     Before adding your first dimension, make sure you are in the MODEL side of Paper Space and leave the Vport layer VISIBLE. The MODEL button on the Status Bar should be displayed (see below).

Use ltscale (typed in at a Command: prompt) and change the line scale to .75. This changes the scale of the dashes in the dashed lines (center and hidden).

To help you with the selection of the dimensioning commands, you may wish to open the dimensioning toolbar and place it on the AutoCAD window. Remember you will find this under Toolbars... on the View menu.


To add dimensions efficiently, you should create a dimensioning style. Dimension styles can simplify dimensioning by predefining certain dimension formats. The dimension Style... dialogue box is available under the Dimension Menu as Style... or by clicking on the Style button on the Dimension toolbar.

FIGURE 3 shows an example of the Dimension Style Manager dialogue box. Through this box, you can modify the dimension parameters, and create different dimensioning styles under a name of your choosing. These dimension styles can be defined and utilized later so that you do not have to set each dimension individually.

Let's define a new dimensioning style. You can either edit an existing style or create a new one. Notice the current style displayed in the style box is called Standard. This is AutoCAD's default dimension style. For this tutorial, you will create a style based on the Standard style, and save it under a different name.

 

FIGURE 3

To create your new dimensioning style, click on the New button. The Create New Dimension Style dialogue box will appear. In this box, you can begin the definition for a new style and if can select an existing style to base this new style on. See FIGURE 4.

FIGURE 4

To create your new dimension style, type Mystyle in the window by the heading New Style Name:, make sure that Standard is selected in the window labeled Start With:, and then click on OK. The Modify Dimension Style dialogue box will appear. NOTE: If needed, you can use the Use for: window to select the type of dimensions (radial, diameter, linear, etc.) you wish to create a style for.

The Modify Dimension Style has been designed so that you can define a variety of dimension parameters. When it first appears, the Lines and Arrows tab should be showing (see FIGURE 5).

In all of the dimension dialogue boxes, an example of the changes you select will be displayed in the window on the upper right. NOTE: Occasionally this window does not display the changes correctly, so do not panic. When you change to a new tab, the window will show your changes to the style correctly.

FIGURE 5

The changes you should make in the Lines and Arrowhead dialogue box should include the following:

Under the Dimension Lines section set Spacing: to 12 (this sets the space between stacked dimensions). NOTE: The minimum space between dimensions is 6mm; however, you will have some long dimensions and will be orienting your dimension text horizontally so you will need to have more space between the stacked dimensions.

Under the Extension Line section set Extend beyond dim lines: to 3 (this indicates the distance the extension line should extend past the dimension line) and set Origin Offset: to 1.5 (this determines the gap between the extension line and the element being dimensioned).

Under Arrowheads set Size: to 3 (this sets the arrowhead lengths), and make sure that in the windows by the 1st, 2nd, and Leader headings they show Closed filled.

Under Center Marks for Circles set Size: to 1.5 (this sets the length for half of the lines for a center mark).


Next, click on the Text tab to bring that dialogue box forward. See FIGURE 6. Inside this box, make the following changes or make sure that the following categories are set:

Under Text Appearance —Make sure that the Text style: is Standard and the Text color: is ByBlock (this allows the color to be controlled by the layers and assures that the font is the default).

Under the Text Placement section—Select Centered in the window by Vertical: and Centered in the window by Horizontal: (this orients the text to the dimension lines). NOTE: If a dimension placed in this location does not work well with other dimensions, you can easily move a dimension to a new location after it is placed.

Under the Text Alignment section—Click on the Horizontal button (this orients all of the dimension numbers to a horizontal position).

In the window beside the heading Offset from dim line: type in 1.5 (this changes the size of the gap in the dimension line by establishing how far the dimension line should be from the text).

FIGURE 6


Now, click the Fit tab (see FIGURE 7) to bring the Fit dialogue box forward. In this box make the following changes or make sure that the following are set:

Under Fit Options—Click on the button next to the heading Either the text or the arrow, whichever fits best (this gives you the flexibility to have a dimension inside or outside of the extension lines).

Under Scales for Dimension Features—select Scale dimensions to layout (paperspace).This scales the elements of the dimensioning system (arrows, numbers, etc.) to the scale used in paperspace. NOTE: You need to have dimension elements print in a 1:1 scale for readability, regardless of the drawing scale in the print. Setting the dimension scale to match paperspace, assures that the dimensions will match the 1:1 scale of Layout1, even though the drawing scale is 1:2 (the scale we used during Solview).

Under Fine Tuning:—select Place text manually when dimensioning (this gives you the flexibility to place a dimension in the most appropriate position relative to other dimensions).

FIGURE 7


Now, click on the Primary Units tab to bring this dialogue box forward. See FIGURE 8.

In this box, make sure that Linear Dimensions are set to Decimal, Precision is set to 0.0000, and Round off is set to 0.

Under Measurement Scales—leave the Scale factor at 1.

Beside BOTH areas labeled Zero Suppression—click on the check box next to Trailing (this will remove any excess 0's after a number.

FIGURE 8

 

Click on OK to return to the Dimension Style dialogue box. When the Dimension Style Manager box appears, make sure that Mystyle is still highlighted in the Styles: window and then click on the Set Current button to set this as your dimension style and then on Close the close the window. See FIGURE 9.

FIGURE 9

Finally, click the Save button under the Dimension Style window and then OK to exit the Dimension Style dialogue box.

 

You have now created a dimensioning style!


Save!!!


STEP 4

     You can now add your first dimension.

Look at Figure 10 to see an illustration of the first dimension you will add.

Before adding this dimension, make the TOP View active, change to the Top-DIM layer.

NOTE: AutoCAD will not allow you to place dimensions in a view unless you have matched the layer to the view. If you attempt to add dimensions in a layer that does not match the view, you will get an error message.

 If you want a better view of the TOP view, change to the PAPER side of Paper Space by clicking on the MODEL button at the end of the Status Bar so that it changes to PAPER and use a Window Zoom to enlarge it on the screen. Change back to the MODEL side of Paper Space before adding the dimension.

 

FIGURE 10

The dimension, shown in FIGURE 7, will be added with a Linear dimension.

Activate the Linear dimension command. When the prompt reads: Specify first extension line origin or <select object>: use the INTERSECTION Osnap and select position A (the first extension line origin) shown in FIGURE 7.

—Prompt: Specify second extension line origin: Use the INTERSECTION Osnap and select position B (the second extension line origin) shown in FIGURE 7.

IMPORTANT NOTE: Use the Intersection Osnap and not Endpoint to select the extension line origin points for dimensions in a 2D object. If you already have dimensions in place, you can accidentally select the end of an extension line instead of the object line. If your dimension numbers are wrong, you may have done this. All of the numbers in this tutorial should be in whole numbers.

NOTE: Use Osnaps when placing dimensions to be sure they are accurate.

The next prompt will ask you to locate the position of the dimension text for this dimension. You need to place the dimensions approximately 20mm away from the figure. Remember that the drawing is scaled to 1:2. Since the first dimension you are adding is 26mm, a little less than this would be 20mm. If you want to be more accurate, you can add a line 20 beyond the figure as a guide and then remove it.

NOTE: You will be able to drag the dimension number into more than one position relative to the dimension lines. Place the dimension number to the position you see in the figures. They may not be perfectly placed, but you have the flexibility to move them if you wish. This will be covered later in the tutorial.

—Prompt: Specify dimension line location or [Mtext/Text/Angle/Horizontal/Vertical/Rotated]: Select the location for the dimension text by clicking the Left mouse button on the screen.

—Prompt: Dimension text <26>: Press Enter to accept the dimension.

Now, use the same technique to place the rest of the dimensions seen in FIGURE 11.

If you Zoomed to display a larger view of the TOP view, change to the PAPER side of Paper Space, use Zoom Extents, and then Window Zoom around the next view before you add dimensions to it. Be sure to return to MODEL side of Paper Space and change the layer to match the view.


 

FIGURE 11


SAVE!

STEP 5


     You will now add dimensions using a Continue dimension. A Continue dimension allows you to place dimensions in a continuous row so they are aligned to each other and share an extension line.

Look at FIGURE 12 to see where the first Continue dimension should go. You may want to change to PAPER side of Paper Space and zoom in, but remember to change back to the MODEL side of Paper Space before dimensioning.

FIGURE 12

Prompt:Command: Type dimcont or select the Continue dimension button on the Dimensioning toolbar.

—Prompt: Select the dimension to continue: Click on the bottom horizontal dimension (size is 26), in the top view, that you already added to the drawing (see FIGURE 12). NOTE: If you were continuing the dimension you had just added, this prompt will not appear and only the next prompt is shown.

—Prompt: Specify a second extension line origin or [Undo</Select] <Select>: Select the right bottom corner of the rectangular slot (for the 51 dimension). NOTE: If you get are trying to add a continue dimension to a dimension other than the last you added, you would use the Select option by typing s and then pressing Enter. AutoCAD would then give you the prompt: Select the dimension to continue:.

Prompt: Dimension text <51>. Press Enter.

—Prompt: Specify a second extension line origin or [Undo</Select] <Select>: Select the other edge of the slot that measures 25 to add this dimension to the continued dimensions. Do not worry if the number does not go between the lines. You will take care of this next.

ERASING A DIMENSION: If you need to erase a dimension, the Erase command functions the same for dimensions as it does for other elements. Since dimensions are grouped elements, you can click on any part of the dimension, and the whole dimension selects.

NOTE: If you are adding a CONTINUE dimension that will be connected to a dimension you just added, you do not have to identify the dimension the continue dimension will be attached to. For instance, to place the second Continue dimension in the TOP view, you do not have to identify the extension line because you have just placed the 51 dimension it will be attached to. When the prompt reads: Specify a second extension line origin or [Undo/Select]<Select>: , select the left side of the 25 mm slot to place the dimension. To use this feature of this dimension command, you must select the prior dimension so that its second extension line is the extension line the continue dimension line will connect to, otherwise, the dimension will indicate the wrong value.


Since you are an intelligent person, I know you have saved lately!


STEP 6

   Look at FIGURE 13. This figure shows the RIGHT SIDE view with a vertical dimension added. Use the Linear dimension procedures to add the dimensions shown in this figure.

Zoom in if you wish. Change the layer.

FIGURE 13

Once you have the vertical dimension in place, examine FIGURE 14 to see where you need to place a Continue dimension adjacent to it.

FIGURE 14

 

Move back to the TOP view so you can add another Linear dimension and two Baseline dimensions. A Baseline dimension allows you to stack dimensions off of a common point of origin. Look at FIGURE 15. The dimensions of 62 and 103 are Baseline dimensions in this illustration.

NOTE: Don't have enough room to place your dimension? Remember you can stretch the size of the viewports.

FIGURE 15

Begin by adding a Linear dimension (30) for the location of the center of the counterbored hole from the top edge of the view. Remember to change your Layer.

Now, you are ready to add a Baseline dimension.

At a Command: prompt type dimbase, select Baseline on the Dimension Menu, or click on the Baseline button .

—Prompt reads: Select baseline dimension:. Click on the dimension text of the 30 dimension. NOTE: Like the Continue dimension, the baseline dimension will only ask you to specify an existing dimension as a base if you are not using the last dimension you placed as the base dimension. When you change viewports, AutoCAD will prompt you to select this dimension.

—Prompt reads: Specify a second extension line origin or [Undo/ Select] <Select>: Select the endpont of the vertical line on the right edge (shown for the 62mm dimension in FIGURE 15) . NOTE: If you wished to use a dimension other than the last dimension you placed in a view as your base dimension, you would use the Select option. The Select option would initiate the prompt: Select baseline dimension:

—Prompt: Dimension text <62>:. Press Enter. The dimension appears and is stacked outside of the 30 dimension.

—Prompt: Repeat for the second Baseline dimension of 103.


STEP 7

     The three features you will now dimension are the countersink, the counterbore, and the arc.

The countersink will use a Diameter dimension, and its Mtext option, to add the additional text and symbols required to define this feature. The arc (since it is less than 180 degrees) will use a Radial dimension.

Let's begin with the countersink. Look at FIGURE 16 to see the placement of this dimension.

 

FIGURE 16

Select Diameter under the DIMENSION Menu, or type dimdia at a Command: prompt line, or click on the Diameter button .

When the Command: prompt reads: Dimension line location (Mtext/Text/Angle): click on the outside circle of the countersink approximately where the arrow touches it in FIGURE 16, but DO NOT PRESS ENTER. Now, select the Mtext option and press Enter. The Multiline Text Editor dialogue box will appear. See FIGURE 17.

FIGURE 17

Once the Multiline Text Editor dialogue box opens, use the drop-down menu, under Character, to change the font to GDT.

Check the font size to be sure that it is 6 points or change it to 6. (NOTE: You need to check the Font size for every text or symbol component you place in this box since it may change.)

Place your cursor IN FRONT of the brackets (< >) in this dialogue box. The brackets contain the diameter symbol and the size of the outer circle of the countersink although it is not displayed in this window.

With the cursor in front of the the brackets, you can add the diameter symbol and type the diameter value of the smaller circle. To add the diameter symbol, click on the Symbol drop-down menu, on the right side of the dialogue box, and select Diameter. See FIGURE 18.

FIGURE 18

The text %%C should appear in front of the brackets (this is AutoCAD's code for the diameter symbol).

After the %%C, type 20, for the diameter of the smaller hole, followed by a comma.

Next, you need to copy the Countersink symbol from the GDT Character Map dialogue box. To access this box, again click on the Symbol drop-down menu and select Other... See FIGURE 19.

 

FIGURE 19

The Character Map dialogue box displays the dimensioning symbols that you can select in this font. Locate the V (the countersink symbol) and click on it. It should highlight. See FIGURE 19.

Click on the Select button, and the countersink symbol should appear in the window next to the heading Character to copy:.

Click on the Copy button, followed by the Close button, to return to the Multiline Text Editor dialogue box.

Insert your cursor just before the < > and press the RIGHT mouse button (a small pop-up menu will appear). Select Paste to add the countersink symbol to the other text (see FIGURE 20).

FIGURE 20

Add a space behind the countersink symbol and then type in 82 and select Degrees on the Symbol drop-down menu. Your text for the countersink hole should look the text in FIGURE 21. Press Enter until the text is placed on your drawing.

FIGURE 21

 

Examine FIGURE 22. Notice where the arc dimension should be placed. Use the Radial dimension (dimrad) and try to place this one on your own. Remember to read the prompts.

FIGURE 22


SAVE!!

STEP 8

     The next step is to dimension the counterbore in the TOP view. Remember to change your layer.

Use the Diameter dimension and Mtext option to make the counterbore text look like the one in FIGURE 23. NOTE: The counterbore symbol is on the LEFT side of the countersink symbol, you just used, in the GDT Character Map dialogue box. The vertical sides of this symbol do not show in the dialogue box, which makes it difficult to find.

FIGURE 23


STEP 9

     Look at FIGURE 24. Notice that the position of the 25 for the slot in the bottom of this view has been changed from its original position. The dimension number for this feature would work better if it was moved to a new location. To move this text, click on the Edit Text button on the Dimension toolbar. Click on the 25, and use your LEFT mouse button to slide it to the new location.

FIGURE 24

Now, look at FIGURE 25, below, and add any dimensions that are not already in the drawing.

 

FIGURE 25

 

 


STEP 9

     Your drawing needs a Metric Flag to indicate that it is in the Metric System.

Look at FIGURE 26 again to see approximately where the Metric Flag should be placed. Use dtext to add this text in the PAPER side of Paper Space. The text should be 5mm high.

To finish the Flag, add a border line that surrounds it like the one shown in FIGURE 25. HINT: Try using the Rectangle command under the Draw Menu. The rectangle should be about 1.5mm away from the text.

Now, it is time to edit the text in the titleblock and print your drawing.

Edit the text in the titleblock as needed. Remember that your drawing is in a 1:2 scale.

Print the file.


CONGRATULATIONS!!!

You have completed the LAST AutoCAD Tutorial for this course, and you have done very well.

I hope you learned a great deal and will explore this program further on your own.


AutoCAD is a registered trademark of AutoDesk, Inc.
AutoCAD Tutorial 6: For Release 2000 was written by:
Dr. Alice Y. Scales, Ed.D.
Graphic Communications Program
Department of Mathematics, Science and Technology Education
NORTH CAROLINA STATE UNIVERSITY
This work is copyrighted and the property of Alice Y. Scales and is not to be copied without permission of the author.
10/30/01


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