AutoCAD Plot Styles and Lineweights Q & A
Plot styles are often a subject of confusion for AutoCAD users. In the real world of CAD in the workplace, each company usually has their own individual company standards, which makes it difficult to know what is the right way, or the best way, to set these up.
In this post we answer some FAQs regarding plot styles. Keep in mind that “Print” and “Plot” mean the same thing in AutoCAD, and that printing can be done to a PDF file, as well as to a sheet of paper. The principles below apply to either PDF creation, or paper printing.
Q: What is a plot style?
A: A plot style is a color and lineweight table, saved in special file in AutoCAD, that tells the printer/plotter how to take the object colors in a CAD drawing (red, yellow, cyan, etc.) and convert them into various lineweights in the printed drawing.
Q: Why do I need to use a plot style?
A: You need the plot style table to control the lineweights in your printed drawing. Carefully controlled line weights can make the difference between a crude, hard-to-read drawing, and a professional-looking work of CAD art.
Q: What if I don’t want to select a plot style when I print?
A: All plots are done using a plot style table. If you don’t choose one, AutoCAD uses a default plot style file named acad.ctb, which gives all colors the same lineweight, and prints them using the object colors that you see on the screen. This is usually not optimal.
Q: How do I choose the plot style I want?
A: In either the Plot dialog box, or the Page Setup Manager dialog box, the Plot style table selector is in the top right corner.
Q: I don’t have a plot style table. How do I create one?
A: You can create one by choosing “New…” from the pull-down list of plot style tables. Type in the name of the new plot style. Then edit the new file using the Plot Style Table editor. You get to the editor by clicking on the button marked with a red arrow in the box above. Click on the Editor button and you will see a box like this:
You can click on the tab at the top to switch to Table view, as shown below:
In either Form View or Table View, click on a color and set it up, then go to the next color. I usually go to Form View and start with Color 1 (red) and set the color to print black, then pick a lineweight for that color. Then I move to the next color on the list, yellow, and repeat. Then on down the list.
Q: Do I have to set up lineweights for all 255 colors?
A: No, usually all you need for black and white printing are colors 1 through 9. Color 8 is usually set up to print in a medium gray tone, usually at 30% to 50% screened, with the color set to black.
Q: What lineweights should I assign to the colors?
A: That’s up to you, the designer, unless you’re working with a company that requires that you follow their standards. Typically, an established company has created a company-standard plot style table, which is saved in a CTB file such as XYZCOMPANY.ctb. The CTB file is saved in a hidden AutoCAD support folder. I’ve worked with multiple companies, and they each have different company standards.
Q: I want to set up my own Plot Style Table. Where do I start?
A: Choose a plot style table name, then set up a range of line weights, typically ranging from about 0.07 mm to 1.0 mm. This varies depending on the type of work the company does. You could make Color 1 (red) the thinnest line and color 7 (white) the thickest. I have worked with companies who use this simple arrangement. Other companies set the brightest colors on the screen, such as color 2 (yellow) and color 4 (cyan), to print in medium or bolder line weights.
Q: What plot style table do you use for your work?
A: I thought you’d never ask. Here is a printout of the plot style table that I currently use:
In my plot style table, colors 10 through 249 print using the actual object colors, not black. The color setting for these colors is “Use object color.” If I want to make a color site plan with black linework of various weights and several areas of solid color hatching, I put the linework on colors 1 through 9, and the color hatching on colors 10 through 249.
As you can see, colors 250 through 255 are set to print black, with screening of 10% through 80%, so the appearance of the gray colors on screen approximately matches the printed gray tones.
Q: My lineweights are shown in inches. How do I change them to millimeters?
A: The radio button to change the line weight widths from inches to millimeters is behind the button “Edit lineweights…” in the Plot Style Table Editor dialog box.
Q: Once I set up my plot style on my computer, will it show up in the plot style list in all my drawings?
A: Yes. If you are working with a team, each member of the team will need the CTB file loaded on their computer.
Q: Can the plot style table file be shared by team members on a network server?
A: Yes, we’ll cover sharing and loading the CTB file in another post.
Hope this helps. If you have any questions or comments, please forward them to me in the box below.
Keep on CADDing! :-)