Beams and walls will automatically trim each other based on the strengths of their Building Materials.
It is called Priority Based Connections (PBC).
So one element will already be trimming the other (you can usually see this when you select them in 3D and look at the selection outline).
The part of the element that is automatically cut away can not act on any other elements in an SEO, because it doesn't exist any more.
To stop this from happening place them in different layers and make sure the layers have different Intersection Priority numbers (you need to make sure the layer combinations are updated as well).
Or you can place them in just one layer and set the IP number to 0 (zero).
But be aware that this will affect the connection of all elements in theses layers.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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