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Paul Andersen
2005-11-17, 05:49 PM
We are currently working on a project that is utilizing HSS Hollow Structural Sections almost entirely. The structure has most of these members being placed at various vertical and horizontal angles and all of the members will be exposed so connections and mitering / coping of members are critical. We have run into a few interesting issues that I would like to confirm with some other users to verify that it's not just our setup.

1. Certain HSS framing members seem to place below the intended level when viewed in section or elevation views but the elevation parameter in the members properties displays 0'-0". As a test place an HSS6X6X.500 in a plan view and then look at it in elevation or section. Ours is currently placing it 1" below the intended elevation when dimensioned. An HSS4 1/2X4 1/2X.500 places 1 3/4" below the level. Not all members place below the level, we have primarily seen this with the smaller square tubes.

2. The tubes at the top level of our structure are rectangular in shape and are rotated 90 degrees about their center. When the side of the member is viewed in elevation with model graphics style set to hidden line the hidden lines for the thickness of the tube display outside of the tube and correspond to the dimensions of the member as if it weren't rotated. As a test place an HSS20X12X.625 in a plan view. Set it's angle parameter to 90 degrees and view the side of the member in elevation (hidden line mode). Before I dive into the family has anyone adjusted the hidden lines in this or a similar family and had it display correctly when rotated?

It would be nice to be able to place complex structural framing in 3D stick symbol fashion with constrained workpoints (which could be adjusted later) to set the geometry of the structure and then come back and flesh out the member sizes and justifications based on the wireframe. Currently we are creating a lot of in-place families (beams and columns consisting of profile generated sweeps) to get the level of control and overall look we require on this project.

kmarsh
2005-11-17, 06:58 PM
I know that I should be running out money for all the 2 cents i've been putting in lately but read my post in this thread:
http://forums.augi.com/showthread.php?t=26597
I ran into the same exact problem but got no response.
-ken

Paul Andersen
2005-12-22, 08:35 PM
Started a job today that required HSS6x6x.250 members for framing the perimeter of a balcony. Placed the member in plan view and ran into one of the same problems outlined in my previous post above. The top of the member was held down 1" below the level it was placed. I actually had some time to look into this some more and I believe I've found the culprit. If you open the family (HSS-Hollow Structural Section.rfa) and take a look at the left or right elevation you will see that there is an angle parameter inside the tube that is tied to a reference line. The reference line originates at the center of the tube and goes up 4". Any tube with a height less than 8" (4" from center to top of tube) will be held down from the level by the difference of 4" - 1/2 of the tubes overall height. The fix is rather simple. Drag the top line end handle of the reference line down until is only a 1/4" above the center line of the tube or whatever your preference. At a 1/4" you could theoretically have tube sizes down to a 1/2" square without any problems. I've tested this with several sizes and rotations and have not had a problem since tweaking this. I know I've had this same issue with a few other framing families and will try to list them as I find them. Hope this helps somebody else out because it was driving me a little crazy. ;-)

Regards,