What is real difference between cut lines and drafting lines ?

[kosta]

Hi ! 

Manual says: 

Drafting line: 

"Simple 2D drafting line. Lines drawn with the Line tool will be in this category by default."

ok, it will be there and ? How that will help if it will be there ? 

Cut line:

"Contour line of a 3D element on a cutting plane."

Here only difference is that cut lines are treated as lines like if they are cut by cut plane, displayed in bold if  "bold cut lines" are enabled (which is not printable anyway).

What is real usage to have them separated ? except having them theoretically separated.

P.S, it also says: 

Line categories can be useful if, for example, you have exploded a composite wall into its constituent lines and fills. By default, in the Line Tool’s Properties Panel, all the contour lines are put into the “Cut line” category, while all the skin separator lines are put into the “Skin Separator” category.

How can I explode composite wall ? like I can explode vector PDF for example, or that is different explode ? 

[DGSketcher]

@kosta You have answered your own question, but the final step is using the Detail & Worksheet tools which explode a view to create a 2D image. These line properties are present in Graphic Overrides so still serve a purpose even though at first view they may seem redundant.

[Moh]

I've often wondered the same thing.  

The only use I have found for line categories are for controlling renovation overrides.  For various reasons, we do not override drafting fills and lines in our renovation filter options, so if we want the override to apply to a line then we simply change its category to cut line (or skin separator) .  

Keen to hear what others use it for.

You can explode a composite wall with the 'explode' command and it turns it into lines and fills.

[Laszlo Nagy]

From Archicad Help:

https://help.graphisoft.com/AC/25/INT/index.htm?rhcsh=1&rhnewwnd=0&rhmapid=#t=_AC25_Help%2F150_UserI...

Line categories can be useful if, for example, you have exploded a composite wall 
into its constituent lines and fills. By default, in the Line Tool’s Properties Panel, 
all the contour lines are put into the “Cut line” category, while all the 
skin separator lines are put into the “Skin Separator” category.

All other lines are placed into the Drafting category by default. However, if you draw 
lines by hand into a Detail/Worksheet, Patch, or Section/Elevation/IE Window, you can assign 
categories to these lines according to their function in the plan. This way, when assigning 
a display option, even hand-drawn lines can be considered Cut lines or Skin Separator lines.

Assigning line categories can also be useful if you save your file in DXF/DWG format: 
the Translation Setup dialog box allows you to define a separate layer onto which 
Skin Separator lines can be exported.

[Moh]

@DGSketcher.   I'm keen to learn your method for applying Graphic Overrides to lines based on their category.  Could you share please.

Thanks

Moh.

[DGSketcher]

@Moh I see I may have mislead you slightly. I was making reference to the current ability to show & hide skin lines in the Graphic Override settings. It is possible that at some point GS may also include more properties for line processing e.g. to enable the highlight of cut lines etc.