Section lines that can bend, not just step

[Christiaan]

We need to be able to create Section Viewports by bending section lines rather than stepping them. Stepped section lines make for some very messy sections on some building shapes.

 

Edited January 5, 2021 by Christiaan

[E|FA]

@Christiaan Do you think the interior elevations (other than stairs and roof features beyond) shown beyond the section cut particularly important for explaining the project for permits and construction?   In my experience, the doors, windows, wall corners, etc are picked up in plans and interior elevations, and having them shown in section can be helpful but not that important.  I'm genuinely curious about everyone else's experience.

[Christiaan]

I have this debate with myself every time I produce a section. I don't have any hard and fast rule except that whatever looks like it gives the builder the most useful information. 

 

One problem is that it can be a bit of all or nothing. If I'd I had the time I would have configured this section to hide all the partitions, doors and windows but to show background context for things that look weird when you cut through them, leaving them floating in mid-air. Such as balustrades, stairs, pergola etc.

 

Here it is again with background turned off and areas that I would like to see some background context circled in red.

 

[Christiaan]

I followed this approach a little bit on a 1:100 section. You see in the background some balustrades/parapets and the pergola, but everything else is turned off.

[Christiaan]

Also, you can't really see it in these screen shots, but the prints actually look very good because the background stuff is very light.

[thinkingpencil]

I drew four sections each from its own section line. The section lines were joined at angles on plan different to 90deg so that they cut through the buildings on my block site model orthogonally (buildngs not orthogonal relative to eachother). I also drew a simple horizontal "reference datum extrude" across the  entire model to enable each viewport to be easily aligned in elevation. That  extrude's class is later set invisible in VP's, obviously. I drew a polygon from the section lines and pasted that into one of VP's annotations plane to help align them horizontally. Again set invisible afterwards. The model is accurate enough to render with conviction in, say , an aerial view. But messy in the sections. So the final composite of four VPs will rely on 2D graphics in annotations, with the messy graphics set invisible.

 

....so yes I am also waiting for a tool which draws a polygonal section line then creates one Section-VP. I'd be happy with just the information along the line. With no view of objects beyond or behind the cut plane. But that's because I seldom design buidlings without orthogonal plans. And the composite VP I have just made is of a simple site block model.

[shorter]

On 4/18/2023 at 4:27 PM, jeff prince said:

 

This whole thread is interesting, but it begs to question...

Is this an actual Architectural sectioning technique?

I thought the "rules" for sections and elevations was a primary view is chosen which the picture plane is parallel to and then all other features not on the plan are projected/foreshortened.

 

It seems that a different tool would be needed than the conventional section line tool in order to do this properly.

 

I would like to see something like a clip cube, where you could draw an angled polygon to define what you want to keep and then have the stuff outside the polygon removed.  Now that would be useful.  You could then orientate an elevation to this clipped form and have everything projected, either orthographically or in perspective.

 

 

 

It's the same issue with showing detail on elevations way in the distance.  Totally unnecessary, and arguably confusing and error-inducing for construction drawings but great for 'presentation'.  We would issue separate sections.  We would not bother with joining viewports.  We would simply say 'refer to drawing xyz for continuation'.

 

That said, the number of times I have been asked if it's possible to generate an unfolded elevation...

[mike m oz]

Whilst the 'author' might understand what is going on with complex sections like those proposed, will the contractor, subcontractors and tradesmen understand it.  The risk is them not understanding it and errors occurring on site.  The resulting argy bargy about who is responsible and who is going to pay to fix the mistakes is territory best avoided.