Trim Elements to roof / Shell Error - extra trimming

[Karl Barker]

I apologise if this has come up before, but it appears to be a fundamental issue for me that I can not get my head around why it does not work as it should.
Step 1: Draw wall that runs past another to create a blade wall.
Step 2: build roof above two wall elements.
Step 3: In 3D window, select walls and roof and apply 'Trim Elements to roof / shell' command.
Step 4: watch blade wall dissapear in 3D window yet remain in 2D plan view.

Possible solution, draw new wall beyond as the blade wall.
Well, tried that and the wall disappears entirely in 3D.
Still there in plan though.

Sorry image added for clarity

[Barry Kelly]

Can you post an image or two please?
Barry.

[Erika Epstein]

Karl wrote:
I apologise if this has come up before, but it appears to be a fundamental issue for me that I can not get my head around why it does not work as it should.
Step 1: Draw wall that runs past another to create a blade wall.
Step 2: build roof above two wall elements.
Step 3: In 3D window, select walls and roof and apply 'Trim Elements to roof / shell' command.
Step 4: watch blade wall dissapear in 3D window yet remain in 2D plan view.

Possible solution, draw new wall beyond as the blade wall.
Well, tried that and the wall disappears entirely in 3D.
Still there in plan though.

Sorry image added for clarity

Use the CROP command.
Trimming is an SEO command and the plan view will not show the results of the trim, hence the wall shows in plan when invisible in the 3D window.

[Karl Barker]

Erika, that is what we usually would have done, and still do.
however we are currently in the design phase with this project and are adjusting roof pitches across different terraces.
Hence I wanted to use a live form of trimming.

It seems odd that the operation works both with the roof but also with the walls trimming together.

I wish that it worked like the crop command, but was kept live so the roof could be altered and the wall would follow its height.

Again, one of those commands that is 'almost' there, but not quite.

[NCornia]

Create a duplicate roof in same position as original roof. Offset edges to increase trimming body footprint. Select new roof and in settings select "Contours Down" in Trimming Body field. Trim walls to this roof then put roof on invisible layer.

Trimming bodies are like a veil. Anything that passes through the veil is trimmed away in 3D. Please see this wiki article for more details: http://www.archicadwiki.com/TrimCropAndSolidElementOperation You have more control of trimming bodies with the shell tool: http://www.archicadwiki.com/TrimmingBodyOfShell

HTH

[Barry Kelly]

It looks like your blade wall is completely within the roof perimeter but may be outside of the pivot line.
Change the roof trimming body from "pivot lines down" to "contours down".

Otherwise if you want a live connection you can still use the Solid Element Operations command and trim with upwards extrustion.
This works a little differently to "trim to roof/shell" but is still live.

Barry.

[Karl Barker]

Barry wrote:
It looks like your blade wall is completely within the roof perimeter but may be outside of the pivot line.
Change the roof trimming body from "pivot lines down" to "contours down".

Otherwise if you want a live connection you can still use the Solid Element Operations command and trim with upwards extrustion.
This works a little differently to "trim to roof/shell" but is still live.

Barry.

Thanks for that Barry.
That was what I was after.
Doing extra roofs in order to trim in an early design stage seems like a bit too much of a workaround.
Might have been handy if Cadimage here in NZ could have told me about the trimming option for the roof.

Would also be nice if the trimming would happen in plan as well as in 3D.