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patricks
2005-01-25, 05:50 PM
How do you all make cables or rods like for a cable-tensioned roof structure or something. I was thinking sweep, but if the path is at an angle relative to the ground, how would I make the profile perpendicular to the path?

aggockel50321
2005-01-25, 05:55 PM
You can go to a 3d view, and orient your view to your work (user) plane, by going to View / Orient.

sbrown
2005-01-25, 06:28 PM
Just draw ref. planes at the angle you want, then create your sweep path in those planes.

David Conant
2005-01-25, 06:48 PM
Avoid the temptation to sweep circular profiles to make small radius items. You will add many faces to the project, slowing down graphics activities. Unless you are going to do closeup visualization, polygonal profiles will work and have a much smaller impact on the project.

aaronrumple
2005-01-25, 07:00 PM
...or maybe a fat model line in the correct 3D plane will work.

MikeJarosz
2005-01-25, 07:11 PM
Avoid the temptation to sweep circular profiles to make small radius items. You will add many faces to the project, slowing down graphics activities. Unless you are going to do closeup visualization, polygonal profiles will work and have a much smaller impact on the project.

The top of the Freedom Tower was originally modeled with circular profiles. It looked great, but it slowed the project to an unacceptable crawl.

We switched from circles and the speedup was amazing.

Steve_Stafford
2005-01-25, 07:41 PM
We switched from circles and the speedup was amazing.Just curious, what polygon shape did you switch to?

Scott Hopkins
2005-01-25, 09:23 PM
Avoid the temptation to sweep circular profiles to make small radius items. You will add many faces to the project, slowing down graphics activities. Unless you are going to do closeup visualization, polygonal profiles will work and have a much smaller impact on the project.Is this the case with all circular elements or only small radius circular elements? Just how small is a "small radius" item?

gravelin
2005-01-26, 10:15 AM
Is this the case with all circular elements or only small radius circular elements? Just how small is a "small radius" item?
I've experienced that a 1mm radius is impossible to obtain

J'ai expérimenté qu'un rayon de 1mm est impossible à obtenir.

brian.duguid
2005-01-26, 03:13 PM
Or how about introducing proper elements for these items into Revit so that people can generate them with a little more intelligence embedded?

christo4robin
2005-01-26, 03:24 PM
I've used the model line solution that Aaron proposed with success to model phone lines and electrical wires that were in close proximity to my project.

marty_rozmanith
2005-01-27, 02:37 AM
You can do them today. Like anything else, a tool is only as effective as how it is used. To show the cable in 3D, Revit must tesselate it to display it. If you ask Revit to tesselate a circle, it will, and it takes a long time. The polygon approach is a good one since nobody can typically tell the difference in a rendering or 3D view. If you are making a construction detail of the cables, you just use a circular detail component for the cable profile in the detial view.


Or how about introducing proper elements for these items into Revit so that people can generate them with a little more intelligence embedded?

gordolake
2005-01-27, 05:58 AM
What formula and parameters would you use to show the catenary action on these types of cables?

(the curve assumed by a cord of uniform density and cross section that is perfectly flexible but not capable of being stretched and that hangs freely from two fixed points)


thanks