Monday, June 27, 2011

Low Walls

I was positive I wrote about this in the past but I can't find a post in the pile of posts I've made since the end of 2004. I suppose it could be buried in a post at AUGI...

If a wall is less than six feet (or 2000mm, no not exactly equal to six feet) it will NOT use the Cut line weight, it will only show using the Projection line weight. You can "force" Revit to show it as Cut by setting the Top Constraint to the level above and using a negative Top Offset value to drop it back down to it's intended overall height. A bit obtuse but it works! [Added this: Chris mentioned in a comment, "you can set the Top Constraint to the same level as the Base Constraint and then use a positive value for your Top Offset value."]


I posted this because it came up in a session at RTC (during Harlan Brumm's Troubleshooting class) and then was tweeted.

8 comments:

Klaus Munkholm said...

Great tip Steve, but 2000mm is pretty far off from the exact value ;) which would be 1828,8mm - This behavior is (or were?) well documented - From the help files back in 2009:

"Walls shorter than 6 feet (approximately 1.83 meters) are not cut, even if they intersect the cut plane.

The 6 feet are measured from the top of the bounding box to the bottom of the primary view range. For example, if you create a wall with a sloped top face, when the top of the wall is 6 feet away from the bottom of the primary view range, the wall is cut at the cut plane. When the top of the wall is less than 6 feet, the entire wall shows as projection even where it intersects the cut plane. This behavior always occurs when the Top Constraint property for the wall is specified as Unconnected."

Steve said...

Have you tried it?

In the US metric template a wall doesn't show as cut until it is exactly 2000mm tall (unconnected). 1800-1999mm still shows as projection.

In the US Imperial a six foot tall wall shows as cut but anything less doesn't...

Klaus Munkholm said...

Tested it back in 2009, and the limit back then was precisely 1828,8 mm´s
BUT - Just tested again in 2012, and you´re right! Something have been changed since then, and the limit is now 2000 mm´s ? :-)?

Klaus Munkholm said...

Just had a look at the current help (wiki) and it still says:

Walls shorter than 6 feet (approximately 1.83 meters) are not cut, even if they intersect the cut plane.
The 6 feet are measured from the top of the boun....


Guess Autodesk forgot to update the documentation ;)

Chris said...

OR
you can set the Top Constraint to the same level as the Base Constraint and then use a positive value for your Top Offset value.

Steve said...

True Chris, should have mentioned that option too! It's easier too!

Владимир Паланков said...

What about the curtain walls? I am trying with curtain wall shorter than 6 feet and the curtain panel appears as if it is non-cuttable family. Unfortunately the view range tip does not work here. :-(

Steve said...

Владимир Паланков -

I find the threshold where a CW stops displaying any "cut" line weight is 4 feet. Even a tiny fraction taller and it displays with some acknowledgment of "cut".

How the top constraint is assigned doesn't seem to alter how the threshold is observed anymore, like in the past. Once the wall is 4' or less it only show the Projection line weight.

A Plan Region can influence the display of the CW too (and other walls). Leave the view's View Range setting alone and place a Plan Region that surrounds the CW and drop the cut plane lower for it.