Odd modeling glitch

[Erich]

Just wondering if this is something with my set up or a bug.

I modeled the main floor of an existing house with a composite wall (wood finish/sheathing/studs/interior finish), then I went down a story to model the basement concrete stem wall (solid concrete 6" thick). I had the main story wall overlap the concrete by 1" and had the reference lines aligned with the main floor reference at the stud and the concrete reference at the outer face. This produces the odd leg seen in the attached image.

If I lower the concrete to eliminate the 1" overlap (not the way it is built) or if I place the concrete reference line at the outer face of the composite wall the odd projecting leg disappears.

This seems like a bug to me. Can this be reproduced by others?

[Barry Kelly]

I can confirm that this seems to be a problem.

If the reference lines for the wall above and below line up then the Priority based Connection works but there is a projection as you described.

If the reference lines are on the outsides of the walls (i.e. they don't line up) then the walls trim fine but the PBC doesn't work and you have to resort to Solid Element operations.

Barry.

[Erich]

Yup, same behavior I am seeing.

Reported to GS.

[Barry Kelly]

It seems this bug was reported during beta testing for 18 and has been closed - doesn't say if it was resolved or not.
I have added a comment to the bug report in the hope that it will be re-opened.

I have tested both 17 & 18 and it happens in both.

Barry.

[David Maudlin]

Erich:

When I have run into this, I have had success changing the Junction Order of either the upper or lower walls.

David

[Erich]

David,

I played with the junction priority a bit (both walls were initially at and it does help in that now the little stub of wall is at least within the confines of the modeled elements (as shown in the image on the right). If you then go and set the "End Surfaces: Override using adjoining walls" check box you can get the image on the left.

Still, this seems like a LOT of extra effort for something that should just work in the first place. It seems like a bug particularly since the little stub of wall extends beyond any model element if you don't have the junction priority changed. Something that will now need to occur repeatedly throughout a project. I also only played with this little corner so far. I did not yet check what happens elsewhere as the junction priority was change to fix this corner. I suspect that I shifted problems elsewhere.

If I had read the manual from cover to cover, I might have caught this:

Wall‐Wall Intersections
• Requires Reference Line intersection
For Wall‐Wall junctions, it is not enough that they collide: their reference lines must also intersect. The element (or skin) with the higher‐priority Building Material will cut the one of a lower priority.
• Junction Order for Equal‐Priority Walls
If two Walls of the same priority meet (their reference lines intersect), use Junction Order to control the element level junction.

But I am not sure I would have realized this was the issue either.

[Erich]

It is also odd that changing the junction priority of the lower concrete walls did nothing but changing that of the upper composite walls changed the intersection.

[David Maudlin]

Erich wrote:
It is also odd that changing the junction priority of the lower concrete walls did nothing but changing that of the upper composite walls changed the intersection.

Try changing the upper walls to a higher Junction Priority, or the lower walls to a lower Junction Priority.

David