the key to standardizing annotation in cad files

7/30/2019 The Key to Standardizing Annotation in CAD Files

1/8

Picks and Clicks: The Key to Standardizing Annotation in CAD Files

Professional Surveyor Magazine - June 2011Jennifer DiBona

Part 1

The issue of CAD standards has long been one of my pet projects when working with clients. Its the universal problem, as folks from every officeconfess that CAD standardization is either non-existent or, at least, could be better.

In my experience, the single most-intimidating aspect to developing a CAD standard is deciding how to standardize annotation in order toaccommodate the multiple scale factors used in a typical plan set. Other types of sheets surveyors and civil engineers may have to produce are:

a cover sheet (at 1:1 or no scale),

one or more project or phase site plan sheet (at 1:50, 1:100, 1:500, 1:1000, etc.),

plan and profile sheets (at 1:30, 1:50, etc.), and

detail sheets (at 1:1 or no scale).

Its not an easy issue to resolve, and CAD programs seem to vary from bad to worse in their ability to manage multiple scales within a single CADfile.

Some of the information provided here is very basic, but in my experience even long-time CAD users struggle a bit with the under-the-hood

details about annotation sizing. So, that being said, where should you start?

Determine the Plotted Size, Plotted Height, Plotted Distance of Everything

The most important first step when developing a CAD standard for annotation is to determine the desired plotted size of annotation entities. And,when we discuss annotation, we must remember that this encompasses more than just text; it also means linetype patterns and dimension

styles.

Here are several sample questions to ask when developing a CAD standard for annotation:

When plotted, what is the height (in inches) of the text displaying:

- the project title in the title block?- the road name?

- contour labels?- property line bearings and distances?

When plotted, how far off the property line (in inches) should the bearing and distance label be placed?

When plotted, what is the distance (in inches) between labels along a contour?

When plotted, what is the length (in inches) of the arrowheads at the end of dimension objects?

When plotted, what is the distance (in inches) that the extension line extends beyond the dimension line?

When plotted, what is the length (in inches) of the dashes and gaps in the linetype used to show existing contours?

Overwhelmed yet? Dont be. Once you commit to the size or height of a few entities, the rest come fairly easily just because you know that youwant one entity a little smaller or a little bigger than another.

The remainder of this column covers the issue of standardizing text sizes in your CAD files. Future columns will cover the other questions relating

to linetypes and dimension styles in much more detail.

Standardizing Text Sizes and Placement

Although text height can be set to any desired value, the most commonly used height for plotted text incivil/survey drawings is 0.08. There are several other standard text styles (corresponding to the height of

the plotted text), known as Leroy, that have been adopted from the days of hand and technical lettering.

Even though the Leroy text style usually has a Simplex font, the naming convention is widely acceptedto describe text of a specific height regardless of its font. For instance, L80 text refers to a Leroy styletext that plots 0.08 high; L100 is Leroy with a plot height of 0.10; and L200 is Leroy with a plot height of0.20. Other standard heights and style names are shown in figure 1.

L80, or text that plots 0.08 high, is generally used for basic text such as bearings and distances, contour

labels, and notes. For more prominent text such as road names or parcel numbers an L150, or textplotting 0.15, may be used.

You may be saying, Yeah, thats great and all, but when I enter text it asks me for the height of the text

to be placed in the drawing, not its plotted height. If you use the generic commands for placing text, thatis true. However, most civil/survey programs have specialized commands for labeling that also take intoaccount a horizontal scale that you specify independently for each drawing.

For instance, in Carlson Software or Civil 3D, you can specify program defaults so that bearing anddistance labels always have a plotted height of 0.08. Then, as each new drawing is started, you set itshorizontal scale. For a drawing with a horizontal scale set to 1=50, the bearing and distance labels will be placed in the drawing at a height of

4.0 (0.08 x 50 = 4.0). For a drawing with a horizontal scale set to 1=100, the bearing and distance labels will be placed in the drawing at aheight of 8.0 (0.08 x 100 = 8.0). The plotted height never changes.

Consider what a written standard for annotation would look like if we did not base the standard on the plotted size but on the actual drawing size

of text...

In all 50-scale drawings, bearing and distance labels shall be placed in the drawing at 4.0 high.

In all 100-scale drawings, bearing and distance labels shall be placed in the drawing 8.0 high.

In all 50-scale drawings, all property corner labels shall be placed in the drawing 3.0 high.

ShareThis

Page 1 of 2The Key to Standardizing Annotation in CAD Files

12/3/2012http://www.profsurv.com/magazine/article.aspx?i=70953


2/8

In all 100-scale drawings, all property corner labels shall be placed in the drawing 6.0 high.

Unless otherwise specified, all other text in a 50-scale drawing shall be placed in the drawing 4.0 high.

Unless otherwise specified, all other text in a 100-scale drawing shall be placed in the drawing 8.0 high.

Now, with the understanding that all annotation sizes must be scaled by the horizontal scale, we can simply say:

All road names shall be L150.

All property corner labels shall be L60.

Unless otherwise specified, all other text shall be L80.

As you can see, because the text sizes refer to a plotted height, it makes the writing of CAD standards for annotation remarkably easier.

It is also important to note that, when placing text in a drawing, parameters other thantext height can be adjusted to get the desired look. One of these parameters is the

distance a label is placed above or below the line it labels. Figure 2 shows a clip of theAnnotate Defaults dialog box in Carlson Survey 2011.

The text height is specified using the Text Size Scaler value, and the distance thattext is offset from the line it labels is specified by the Text Offset Scaler. Both of thesevalues are plotted distances in inches. You can also see the horizontal scale setting for the drawing. Once plotted, text placed using thesesettings will be 0.08 high, and it will be positioned 0.04 off the line. A good rule of thumb is to set the offset value at one half the text height.

Another example of an annotation standard that can be associated with a plotted distance is how far apart to place elevation labels along acontour. Rather than specifying that contour labels are 300 apart in a 50-scale drawing or 600 in a 100-scale drawing, your standard shouldstate that: On the plotted sheet, contour labels shall be shown at 6 intervals along each index contour.

I hope this information has provided a good kick-start toward your CAD standardization goals and helps get you thinking in plot sizes rather thandrawing sizes. As noted above, future columns will focus on other supposed standardization nightmares such as dimension styles and will alsotouch on some specifics of the different CAD programs. Please dont hesitate to contact me if you have questions. I hope your summer is off to a

great start!

About the Author

Jennifer DiBona

Jennifer DiBona is an independent consultant doing business as That CAD Girl. She is a Carlson Software reseller and provides CAD training,

technical support, and other CAD-related services. Visit her website at www.thatcadgirl.com to find out more.

Back to our June 2011 Issue

Home | Privacy Policy | Contact Us

2012 by Flatdog Media, Inc. Articles may not be reproduced, in whole or in part, without prior authorization from Flatdog Media, Inc.

Website design and hosting provided by 270net Technologies in Frederick, Maryland.

Page 2 of 2The Key to Standardizing Annotation in CAD Files



3/8

Picks and Clicks: The Key to Standardizing Annotation in CAD Files- Part 2: Linetypes

Professional Surveyor Magazine - March 2012Jennifer DiBona

Read Part 1

This months column is the second in a series covering the different aspects of CAD standardization regarding annotation. The first, The Key to

Standardizing Annotation in CAD Files, explains how to standardize text; it appears in the June 2011 issue of this magazine.

The good news is that working with linetypes in AutoCAD or IntelliCAD is much, much

easier than working with text. Unlike text, the size of dashes, gaps, text, or shapesthat define a linetype can be updated easily as the drawing scale changes by using theLTSCALE system variable.

How Linetypes Are Defined

Before I discuss that, lets start with the very basics of linetype definitions. In AutoCAD

-based programs, linetypes are defined in a file called acad.lin. Likewise, IntelliCADs

linetype definition file is icad.lin. You can usually find the .lin files in one of the supportfolders in the program installation folder.

The .lin file is a text file that can be opened and edited in a text editor such as

Notepad. The file is separated into four sections: Standard Linetypes, ISO Linetypes(Metric), Complex Linetypes, and User-defined Linetypes.

A sample of the acad.lin file is shown in Figure 1 with a few of the Standard Linetypes

highlighted.

Using the DASHED2 Linetype as an example, lets look closely at the differentparameters of the definition:

DASHED2This is the name of the linetype.

Dashed(. 5x)_ _ _ _ _ _ _This is a description and sample of the linetype.

AThe letter A represents the type of Alignment and simply means that, when applied to a line or arc segment, the pattern will start and end with

a dash segment (as opposed to a gap). An A Alignment is the only type supported in AutoCAD or IntelliCAD.

.25This represents the length (when plotted at 1:1) of the first dash in the linetype. This setting gives away just how long AutoCAD has been using

the acad.lin file. To draw a dash, a positive number in this field translates to pen-downa shout-out to old pen-plotters!

-.125

This represents the length (when plotted at 1:1) of the first gap in the linetype. Like mentioned above, a negative number in this field used to tellpen-plotters pen-up, creating a gap in the linetype.

The standard AutoCAD or IntelliCAD linetype definitions come in groups of three, suchas DASHED, DASHED2, and DASHEDX2. In each of these cases, the 2 version ofthe linetype has dashes and gaps that are one-half the length of those in the originalversion of the linetype. The X2 version has dashes and gaps that are two times the

length of those in the original.

Tip: If you have a template drawing (.dwt) file or other drawing that you use to startyour new drawings, dont forget to set your PLINEGEN variable to 1 (ON). This

allows polylines to evenly distribute a linetype pattern from the start to the end of thepolyline rather than between vertices. In Figure 2, the image on the left showscontour polylines with PLINEGEN set to 0 (OFF) and the one on the right with thevariable set to 1 (ON).

Looking a little further down in the acad.lin file, you see a section titled ComplexLinetypes (Figure 3). Two of the Complex Linetypes provided in the acad.lin filecontain text strings: HOT_WATER_SUPPLY and GAS_LINE. Looking closely at

these definitions you can see that the only difference between these linetypes and thestandard linetypes at the top of the file is the inclusion of the formatting instructionsfor the text string included in brackets.

Lets use the GAS_LINE linetype to look at the different parts of the definition:

HOT_WATER_SUPPLYThis is the name of the linetype

Hot water supply ---- HW ---- HW ---- HW ----This is a description and sample of the linetype.

AThe letter A represents the type of Alignment.

.5

ShareThis

Page 1 of 2The Key to Standardizing Annotation in CAD Files - Part 2: Linetypes



4/8

This is the length of the first dash.

-.2

This is the length of the gap on the left side of the text to be inserted.

HWThis is the text thats to be inserted into the linetype.

STANDARDThis is the text style to be used.

S=.1

This is the size of the text (when plotted at 1:1).

R=0.0This sets the rotation angle of the text in relation to the line segment to 0 degrees.

X=-0.1This is the distance, in the x direction, that the text is to be shifted to properly position the text between the two adjacent dashes.

Y=-.05This is the distance, in the y direction, that the text is to be shifted to properly position the text between the two adjacent dashes.

-.2

This is the length of the gap on the right side of the text.

Tip: The Rotation parameter forces the text to align with the line regardless of the direction its drawn. This can be problematic with text in alinetype because lines drawn from left to right will produce text that is upright, but a line drawn from right to left will have text that is upsidedown.

Instead of the R (Rotation) we can use a U (Upright) flag. The U flag keeps the text upright in the drawing regardless of the direction the

line was drawn. Just insert U=0.0 in place of the R=0.0 to generate this result.

The polyline in Figure 4 was drawn from the upper left to the lower right and then to the lower left. The picture on the left shows the linetypewhen the Rotation flag is used and the one on the right uses the Upright flag.

Adjusting Linetypes for the Scale of a Drawing

As mentioned previously, linetype definitions are based on a 1:1 scale or the desiredplotted length of dashes and gaps. Obviously, when we are working with boundarylines that are hundreds of feet long, dashes and gaps of 0.5 or 0.25 feet will not be

visible. This is why we change the LTSCALE environment variable. The defaultLTSCALE is 1, and it applies to both Model and Paper Space. It can be changed at anytime and is effective immediately. When displaying a linetype in a drawing, all of the

parameters of a linetype definition are multiplied by the LTSCALE to determine the

actual length of dashes and gaps.

So, when the LTSCALE is set to 1, the length of dashes and gaps exactly matches thevalues specified in the linetype definition. But, once the plot scale of the drawing has

been decided, the most commonly accepted practice is to set the LTSCALE to match

the plot scale. So, lines having a DASHED2 linetype in a 40-scale drawing with theLTSCALE set to 40 will have dashes that measure 20.0 long and gaps that measure10.0 long.

Tip: If you insert your title blocks into Paper Space at 1:1 and then scale the viewport to the plotted scale, you will probably notice that yourlinetypes appear to be Continuous in the viewport. You will need to toggle another environment variable, PSLTSCALE, from 1 (ON) to 0 (OFF) todisplay and plot linetypes properly.

Tip: If you have more than one Viewport in your Layout Tab and the Viewports have been scaled to different scales, set the LTSCALE to 1 and

the PSLTSCALE in Paper Space to 1 (ON) to have the linetypes in both viewports appear and plot properly.

About the Author

Jennifer DiBona


technical support, and other CAD-related services. Visit her website at www.thatcadgirl.com to find out more.

Back to our March 2012 Issue




Page 2 of 2The Key to Standardizing Annotation in CAD Files - Part 2: Linetypes



5/8

Picks and Clicks: The Key to Standardizing Annotation in CADFiles, Part 3: Dimension Styles

Professional Surveyor Magazine - September 2012

By Jennifer DiBona

This months article is the third in a series covering the different aspects of CAD

standardization regarding annotation. Part 1 (June 2011) explains how to standardize text, and

Part 2 (March 2012) explains how to standardize and create new linetypes. This months topic,dimension styles, is probably the least understood and most intimidating, but, by the time you

finish reading this, youll be talking about parent and child styles like a pro!

Components of a Standard Dimension

There are several different types of dimension objects that you can create in an AutoCAD or

IntelliCAD drawing. Some of them are linear dimensions, aligned dimensions, angulardimensions, radial dimensions, and diameter dimensions. Even though the various types areused to dimension different objects (lines, circles, etc.), all dimension objects have the same

general components and can be easily managed using dimension styles.

Before diving into dimension styles, it is helpful to understand the terminology and know the

different components of the dimension object itself. Knowing these details makes it mucheasier to navigate theseemingly endless

settings that are

available in theDimension Styles

Manager (Figure 1).

Defpoints/Origin:

Defpoints (DefinitionPoints) are CAD points

and are placed at the

origins of themeasurement. Forinstance, in Figure 1

the side of the figurehas been dimensioned

as 4.0 long. The origin

points for thedimension are at the

endpoints of one sideof the figure. Althoughthey cant be seen, the defpoints of the dimension object are at each endpoint.

Defpoints are nested as part of the dimension object.

They reside on layer defpoints (which does not plot).Their size and visibility can be controlled by typing DDPTYPE at the Command: line.

Dimension Line: The dimension line component is made of one ortwo lines with terminators (arrowheads, tick marks, etc.) on the

ends that show the space being measured.

Extension Line: The extension line component is made of one or two

lines that run from the origin perpendicular to the dimension lineand then beyond the dimension line for a short distance.

Dimension Text: Text that is centered or placed above or below thedimension line.

Arrowheads: The more generic term for this is terminators; it is

the symbol that is placed at the ends of the dimension line. Ratherthan arrowheads, you can use architectural ticks, dots, or various

other symbols as terminators.

The Dreaded S Word: Scale

Whether its text or linetypes or dimensions, standardizing

annotation always comes down to the question of how to develop a

standard that works for a 1:1 drawing as well as a 1:100 drawing.Believe it or not, dimensions are one of the easiest to manage

regarding scale.

Just as with text and linetypes, the key to standardizing dimensionsis getting everything to look and work right at 1:1. You can draw aline on your screen thats four units long and dimension it with a

linear dimension and decide what you like about it and what you

dont.

For instance, maybe the dimension text is positioned in line with thedimension line and youd prefer it to be above. Or, maybe it is already

ShareThis

Page 1 of 4The Key to Standardizing Annotation in CAD Files, Part 3: Dimension Styles



6/8

above the dimension line, but its too far above the line for your taste.Maybe the extension lines start too close to the origin points for your

liking or extend too farbeyond the dimension line.

Once you make the appropriate changes to the dimension style and itis formatted properly, its a simple matter to change the scale factor to

have it work with other scales. I recommend that you define a customdimension style for every drawing scale you may need.

Parent and Child

Just like text entities, every dimension object added to a drawing is

associated with a style. And, again like text, the default dimensionstyle is STANDARD.

When you first open the Dimension Style Manager, you can see thereare two available styles: annotative and STANDARD. I recommend

that you leave the existing dimension styles intact and create acustom one of your own.

Follow the steps below to create a new custom dimension style for a1:1 scale.

1. Type DDIM to open the Dimension Style Manager.

2. Left-pick on STANDARD and then pick the New button on theright.

3. This opens the Create New Dimension Style window.

4. Enter a New Style Name. The style name should indicate thatthe style is based on scale of 1:1.

5. The new style should Start With the STANDARD style and is to

be used for All Dimensions.6. Pick Continue (Figure 2)

7. When the Dimension Style Manager pops up, notice that the style

you are modifying is TCG_Scale_1.

8. Switch to the Fit tab of the New Dimension Style dialog box andmake sure the value for Scale for dimension features is set to

Use overall scale of: 1.00. This means that this dimension style

will be used to dimension objects to be plotted at 1:1 (Figure 3).

9. You can then switch to the other tabs to make needed changesor adjustments. Figure 4 can be used to identify some commonstyle changes.

10. On the Primary Units tab, you can make changes as needed.

(For this and the remaining steps, the preview window may ormay not truly reflect the expected results. Somerecommendations are highlighted in Figures 5, 6, 7, and 8).

11. On the Lines tab, you can make changes as needed.

12. On the Symbols and Arrows tab, you can make changes asneeded.

13. On the Text tab, you can make changes as needed. Whendeveloping a dimension style standard, I recommend creating anew text style named DIMTEXT (or something similar) thathas a fixed height of 0. This text style should be used for all of

your dimension styles. This allows you to manually control the

dimension text height and manage it separately from other textin a drawing.

Now, with the changes weve made to the TCG_Scale_1 dimensionstyle, a linear dimension and a leader look like Figure 9.

Unfortunately, this isnt what we were looking for. Rather, the textfor the leader should be vertically centeredrather than above the

dimension line. The way we want it to look is in Figure 10.

In short, we want to have the dimension text for leaders to be

positioned differently than dimension text for linear or aligneddimensions. To do this, we will need a child style for leader

dimension objects. Child dimension styles retain most of thecharacteristics of the parent style, but not all. The parent style will

be TCG_Scale_1.

Follow the steps below to create a new child style for leaders usingthe TCG_Scale_1 dimension style.


2. Left-pick on the existing style TCG_Scale_1 and then pickthe New button on the right.


4. Do not enter a New Style Name as the style name remains

the same as the parent.

5. Make sure that TCG_Scale_1 (the parent style) is specified

as the style to Start With:




7/8

6. Pick Leaders and Tolerances as the Use for: setting.

7. Pick Continue (Figure 11).

8. When the Dimension Style Manager pops up, notice that the

style you are modifying is TCG_Scale_1:Leader.

9. Switch to the Text tab and change the Vertical setting forText Placement to Centered.

10. Pick OK to close the Modify Dimension Style dialog box

(Figure 12).

11. After creating the child style for leaders and tolerances, your

list of available dimension styles should look like Figure 13.

Remember, the preview window may or may not truly reflect

the expected results.12. Repeat these steps as needed to fine-tune each type of

dimension object to look the way you want.

If you are using TCG_Scale_1 to dimension features in your drawing,

leaders will position the text in line with the dimension line, and allother types of dimensions will position the text above the dimension

line. After all of these changes, the dimensions should look like theydo in Figure 10.

Styles for Every Drawing Scale

Our last step is to create additional dimension styles that are based

on other drawing scales we may need. Now that our TCG_Scale_1 hasbeen formatted properly, we can use it as a model for the new ones.

Follow the steps below to create a new custom Dimension Style for a1:40 scale:


2. Left-pick on the existing Style TCG_Scale_1 in the left-handcolumn.

3. Pick the New button on the right.


5. Enter a New Style Name. The Style Name should indicate that

the Style is based on scale of 1:40.

6. The new Style should Start With the TCG_Scale_1 Style and is to be used for All

Dimensions.

7. Pick Continue (Figure 14).

8. When the Dimension Style Manager pops up, notice that you are now modifying the

TCG_Scale_40 dimension style.

9. Switch to the Fit tab.

10. Change the Scale for dimension features setting to Use overall scale of: 40 (Figure

15).

11. Pick OK to close.

Back in the Dimension Style Manager, you can see that weve successfully created theTCG_Scale_40 dimension style, but that the leader child style was not created (Figure 16).

So, for every new style based on a different scale, the child styles will need to be recreated.

But, now you know how easy that is to do!

Although Im sure Ill find other CAD standards issues to write aboutin the future, this wraps up the three biggies of text, linetypes, and

dimensions. I hope youve found it helpful. As always, please donthesitate to follow up with me if you have any questions. I hope you

had a great summer!




8/8


technical support, and other CAD-related services. Visit her website atwww.thatcadgirl.com to find out more.

Back to ourSeptember 2012 Issue





the key to standardizing annotation in cad files

Documents