topic Re: Plot Color Lineweights in AutoCAD Forum

Plot Color Lineweights

Anonymous — Thu, 16 Mar 2017 16:28:12 GMT

What are the "Default" plot line weight values AutoCAD has assigned to colors 1 thru 255?

Re: Plot Color Lineweights

rkmcswain — Thu, 16 Mar 2017 16:32:13 GMT

Depends on what you mean by default. Do you mean excluding any plot style assignments?

The following document says "The DEFAULT value is set by the LWDEFAULT system variable, which has an initial value of 0.01 inches or 0.25 mm. All new layers use the default setting. The lineweight value of 0 plots at the thinnest lineweight available on the specified plotting device and is displayed at one pixel wide in model space."

https://knowledge.autodesk.com/support/autocad-lt/learn-explore/caas/CloudHelp/cloudhelp/2017/ENU/AutoCAD-LT/files/GUID-1BB43E62-DF93-494E-ACF2-55824ACD5130-htm.html

Re: Plot Color Lineweights

RobDraw — Thu, 16 Mar 2017 16:34:12 GMT

There are several pen setting files included with AutoCAD. I'm not sure I would consider any of them default, except for maybe Monochrome which has all of them the same.

Re: Plot Color Lineweights

Anonymous — Thu, 16 Mar 2017 16:45:58 GMT

Using the Screening 100%.ctb as an example, each of the colors listed ( 1 through 255) show a lineweight value as Use object lineweight instead of an actual value. If I create a drawing with 255 lines, all on the 0 layer, standard defaults on the layer manager, but assign each line a numbered color instead of by layer. When the lines are plotted each of them will have one of approximately 5 or 6 different lineweights, I want to know what lineweight AutoCAD has defined for each color. If they were all the same, all of the lines would plot the same. This is especially apparent when printed on a black and white plotter.

Re: Plot Color Lineweights

rkmcswain — Thu, 16 Mar 2017 17:33:05 GMT

@Anonymous - I just repeated your test, and I get 255 identical lineweights.

If anyone else wants to try, here is a quick lisp to generate the lines.

(defun c:foo ()
 (vl-cmdf "._line" (list 0 0 0) (list 0.5 0 0) "")
 (setq ent (entlast))
 (vl-cmdf "._change" (entlast) "" "_P" "_C" "1" "")
 (setq y 0.1 col 2)
 (repeat 254
 (vl-cmdf "._copy" ent "" (list 0 0 0) (list 0 y 0))
 (vl-cmdf "._change" (entlast) "" "_P" "_C" col "")
 (setq col (1+ col))
 (setq y (+ y 0.1))
 )
 (princ)
)

Re: Plot Color Lineweights

Anonymous — Thu, 16 Mar 2017 18:10:38 GMT

I reprinted using a large format plotter instead of a printer and now I see, it is not a lineweight difference, but a grayscale difference creating an optical illusion.

On that note, I will change my question.

Is it possible to determine the grey color or light-dark value if any associated with each color?

Re: Plot Color Lineweights

john.vellek — Thu, 16 Mar 2017 18:13:26 GMT

Hi @Anonymous,

I used @rkmcswain's lisp to quickly generate the lines for his test. Then I plotted to PDF with NONE as the plot style.

I don't see any difference in the lineweights.

What is the intent of your question? Are you trying to create a custom plot style or are you trying to get away from using them altogether?

Re: Plot Color Lineweights

Anonymous — Thu, 16 Mar 2017 18:21:29 GMT

I was trying to decide that very question, and determine if I needed a new plot style or not.

Re: Plot Color Lineweights

john.vellek — Thu, 16 Mar 2017 18:27:25 GMT

Hi @Anonymous,

Some users don't use any Plot Styles as they feel it makes their workflow easier. I like to use my custom ones for being able to quickly plot with different styles depending on the purpose of the output. Do you need help in creating a CTB? Have you mapped colors to lineweights for your office?

Please select the Accept as Solution button if my post solves your issue or answers your question.

Re: Plot Color Lineweights

Anonymous — Thu, 16 Mar 2017 18:34:28 GMT

I'm starting from scratch, and determining which Standards will be used from this time forward. I understand the .ctb process, and appreciate the assistance.

Thanks.