AC17 T-Junctions

[KeesW]

Have got my AC17 and thought that I'd try the T-Junction of a timber stud wall lined with plasterboard both sides. One wall was copied from the other so that they are both identical. Plasterboard value is 400, whilst core is 500.

The identical situation created with AC16 worked perfectly - first time.

It seems that 'automatic' wall junctions are going to take some learning.

[Eduardo Rolon]

Start here:

http://www.graphisoft.com/archicad/archicad_17/bim_details/#priorty_based_connections

The new Materials and PBCs require a different way of thinking how we model intersections. Basically the New Materials have intersection priorities in your case you need to check that the Plasterboard Material have a lower number than the Timber Material and that the wall "overlaps/intersect".

Also check in your preferences if you have the intersection Legacy option on.

and please read the Migration Chapter in the help file.

[KeesW]

Thanks Elrolon.
I did look at those references before I got AC17 and will obviously have to do so again - more thoroughly!

I didn't think that I needed Legacy because the walls were taken directly from a freshly installed AC17 library. Note that the timber core has a higher number than the plasterboard.

[Eduardo Rolon]

This might sound weird. Did a test here and was getting your error even after verifying the BMat Priorties twice.

Third time was the charm I had edited the priorities on one BMat and picked another for the composite. Can you verify that you didn't make the same mistake I did.

I have seen a bug when you create a new BMat and AC switches from editing the new one to editing the one you copied from which might be another item to check.

[KeesW]

Ejrolon

I've tried it again and it didn't work. No I didn't make your mistake - although I might have made others.

What I did discover is that increasing the junction property of the leg of the 'T' from 8 to 9 whilst leaving the long arm at 8, removes the plasterboard in the junction. It is not perfect because it still leaves a line. I've attached a screen shot. What am I missing here?

[Eduardo Rolon]

You shouldn't need to use Junction order to fix this.

Lets take it from the Top.

BMat settings: Plywood Intersection Priority = 300. Test Fill = 500

[Eduardo Rolon]

Composite Settings

[Eduardo Rolon]

result

[Eduardo Rolon]

With wall intersections off.

[KeesW]

I've created correct T-junctions with cavity brickwork - but it doesn't work with plasterboard lined timber framed walls. This, unfortunately, is one of our most common wall types.

Unfortunately, brickwork doesn't present correctly. I attach another T Junction in brickwork How can a single skin brick wall present as it does in cross-sections - it should only show horizontal joints. This is the kind of cavalier and careless programming that taints the true usefulness of archicad's 3D presentations.