How to use this chart:
For a given pen width, there are several AutoCAD® colors which can be used. For example, for a rapidograph #1 (0.021" wide) black, you can use colors 1, 33, 65, 97, 129, 161, 193 or 225. All of these colors will plot the same; 0.021 wide black.
Pen weights available are rapidograph 000 through 6, each in 100% black, 50% grayscale and 30% grayscale. Due to difficulity with photo-copying light shades of gray, we recommend only using the 30% pens for poche or hatched areas - not for general line work.
What is low priority, high priority, and 'masking'?
The masking colors, 136 & 137, plot like an eraser; they are "white" in color, and can overwrite or mask other pens. So, if you used the SOLID command to create a solid using color 136, that solid could mask objects "underneath" (in the context of the DRAWORDER command). Objects "above" the solid would print. For example, using this technique, you can hide a portion of a contour line which would otherwise run through text. We prefer using this method rather than AutoCAD's wipeout command, since wipeout it has several known bugs.
When using AutoCAD to print, there is no difference between low priority and high priority color numbers. However, here at the Denver Service Center office, we use Plot Station / PrfGenerator software to print AutoCAD drawings, and it has capabilities that AutoCAD does not have. One such feature is the ability to assign "priorities" to AutoCAD colors. So, using Plot Station, any high priority color will show through the mask colors, and any low priority color will be hidden by mask colors - all of this happens regardless of draworder.
The bottom line:
Unless you're using Plot Station / PrfGenerator here at the Denver Service Center office, use the low priority colors for most objects. Use the mask colors for objects to act like an eraser. And, pay attention to the draworder of objects if you're masking.
Also, be sure you have the latest version of our pen settings file, NPS_HP_Grayscale.ctb.
Should I use colors that are not shown on this chart?
NO! Even though our .ctb files will print colors not shown here (like color 150), please don't use those colors. We are reserving those colors for unexpected uses. In the future, color 150 might plot to a 1" wide line with Mickey Mouse ears every .5". Okay, maybe not, but you get the idea.
Questions or problems should be directed to firstname.lastname@example.org