Question regarding mapping pen colors and line weights in Revit

[eeblack]

I have a question about mapping colors, layers and line weights in Revit to share exported DWG's with our consultants who are using AutoCAD.

Here's what I know so far:
1) I can map up to 16 line weights that vary depending on the view scale.
2) I can adjust the Revit Export Layers settings to map Revit entities to a specific layer and a specific color.
3) I can edit the Import Line weights from CAD file to map a color to a line weight, but this does not affect the settings in Revit - only DWG files imported/linked into Revit.

What I am stuck on, is how do I get Revit to map a color to a specific line weight? When I try some test exports, only the color has been correctly set. If I edit the Settings>Object Styles for everything, aren't these settings over-ridden by the export file settings?

Can this even be done?

As long as the DWG elements are correct by color, can they use a CTB file to map the colors to a line weight, or do they have to modify everything in a labor-intensive effort?

Any help is appreciated. I have searched through several threads on this topic, but none of the answers seemed to address my questions fully.

[Steve_Stafford]

When you export to DWG the presumption is that your projection and cut layer/color assignments will match the "standard" that is required. You may have to create several export files to satisfy different standards and drawing types when you export.

All things being equal, if you open the file and plot the dwg from AutoCAD using the color based pen table (CTB not STB, which is not supported) the "color" assigned to the layer the lines and blocks are on will plot properly according to the CTB.

Revit also creates a .pcp file which can be used by AutoCAD to create a CTB pen table. Either way you should be able to print the set and get the lineweights you were expecting. There may be some subtle issue or glitches based on how a given components was created and therefore what category it is exported as. This can affect what your export layer/color options are. There are also view or element overrides that can affect this.

There are also export Options you need to consider. When you export there are three options for layer/color delivery:
Create By layer and override the elements (overrides deal with differences between elements that have the same layer assignment but "look" different in Revit for some reason)
Create By Layer and no overrides (this forces all exported elements to be bylayer which will change line patterns and colors so that they ARE By Layer)
Create By Layer and Create new layers (this allows Revit to create a new layer when an element has a representation that a single layer will not support)

To put this in a practical example, imagine a Grid which has text, a circle and a line that is usually drawn with a different line pattern than the circle. If this is exported to layer S-Grid and you want elements to use a By Layer setting, what should Revit do?

The first option will override the linetype of the line so that it maintains its appearance. It does so by creating a new linetype/pattern in the AutoCAD dwg that matches the line pattern name in Revit. If you choose the second option you get a solid line for both circle and line which doesn't look so good when you see it or print it. The last option will create a new layer for the Grid Line, S-Grid-1. You end up with S-Grid for the circle and text and S-Grid-1 for the grid Line. All the elements are By Layer.