can someone explain the Function/theory regarding Lineweights

[rjcoolpix880]

UPDATE:
so i have found the visibility settings. Which i knew about the entire time but forgot. It helps some of the problems i mention below, but doesn't fully solve them all. read on...
__________________________________________________________________

Since i have come from a drafting background, as most of us probably have. We are very picky and know EXACTLY what we want our drawings to look like so that they can communicate the design easily and clearly. This is especially true of line weights as they can push and pull things in the drawings. I just started messing around with the line weights in a project i started for school. The difference in school and the "real world" is that they are basically all presentation style drawings vs. construction drawings. My Presentation drawings typically have a little more "pop" than the construction drawings.

The problem i am having is getting things to be the correct line weights. I have taken the drawings from having pretty much no line weights to having better line weights. What i did is go through all the 1-16 default line weights and find out what each was associated with (by changing each to 1"). what i found was (in a section drawing):
1=beyond
2=just beyond section cut
3=families cut
5=all other cuts
thats it!
*edit: this is where visibility settings come in*

Heres what i tried to do, before i figured out the above. I tried to take my floor, for example, and edit the properties and/or material of the floor and change the line type there. But you can't (right?). To me that makes a lot of since. that way i can have some walls that might have a lighter line weight if they are thinner (say a 4" wall), so the lines don't bleed together. Conversely I can have the thicker, more massive wall, have a thicker line weight. Another example: I don't want my steel beams to have such a thick line around them that they look like an "8" shaped black blob, but the wall next to them i want to have a thick line. But revit doesn't seem to work like this. Can someone explain how revit assigns line weights to objects and why if it is automatic it only uses the first 5 out of 16 line weights? (i understand i don't need 16, but if they are there why aren't they used) I also wish that i could tell a material to be cut with different line weights depending on whether it is in a vertical section versus a horizontal plan. i say this because In the above mentioned section with the line weights about right, the plans look like trash.

I ask this because i just don't understand the concept of the way revit thinks about line weights. And i do know about the line work tool but i don't want to use that if possible (more like a last resort). Id rather take each drawing into adobe illustrator and manually tweak the line weights there than use the line work tool...

ps: i wish that there was a way to "reveal line weights" that maybe it would color code each line weight on the actual drawing, it would make tweaking the line weights much easier than changing each one to 1" to find out what object is assigned what line weight.

[DaveP]

Now that you've (re)discovered the Visibility/Graphics dialog box, you'll also want to take a look at the Object Styles under the Settings menu, as well as the Line Styles and the Line Weights.

Revit performs a pretty intricate dance between what's happening to an object (whether it's seen from above - Projection - or sliced through - Cut), what "pen" it's Object Category has been assigned (it's Object Style's Line Weight) and the printed scale of the View.

Let's take a simple example - a Wall. The wall can be seen either from above - for example, a 3 foot high knee wall. That's Projection. Or it can be seen as in the typical floor plan - a 9 foot high wall sliced through at 4 feet. That's Cut. Both the Wall's Projection and Cut "pens" are set in the Object Styles dialog. Don't remember the exact numbers offhand, but let's say the Projection is 2 and the Cut is 4.

Next look at the Line Weights dialog. This is where a "pen" or Line Weight number gets translated to an actual line thickness. Note that this dialog has line weights assigned to a "pen" according to scale. I suspect this is where you're having an issue between the Section and the Floor Plan. You'll want to set up lighter Line Weights for the 1/8" floor plan than you use for your 3/8" Building Sections or your 1 1/2" Wall Sections.

Good luck. Hope this helps.

[dbaldacchino]

Lineweight 1 doesn't mean anything until you assign a thickness to it. It's just a place holder. Once you get in the lineweights dialog, then you'll notice that you can assign different thicknesses to different scales. So now you can have your Lineweight "X" have a certain thickness in a 1/8" scale view (for your plans) and a heavier thickness in 1/2" scale views
(wall sections).

I think it's a very clever system, but to this day I still feel it's hard to manage. A change in lineweight for a specific scale can mess up the visibility of something else that worked fine but it's something that takes trial and error. If you want "drafting" style lineweights (that don't change with scale), just enter the same thickness for all scales. This is how lineweights used to work in CAD. That's what's hard to wrap your head around.

[rjcoolpix880]

Thanks for the tip about Object Styles. that got me very close to being happy with the line weights. I still have the problem with the thinner walls lines bleeding together. Maybe with a bit more tweaking i could get it. I guess you could fake it by making the thinner walls not really walls but some other category, but that's kind of silly, and would probably screw you up if you did it.