I have a trapezoid-ish sketch I am using for a weldment.  When I attach structural members to a corner that is 90 degrees, all is well.  When I attach structural members to a corner that is not 90 degrees, some unusual trimming happens.

Before I add the second group, the corner looks like this:

But when I put the second group on, it cuts the end of the first group to be in line with the second:

The image shows it before I located the sketch, but the cutting still happens after it is located.  If I create the structural member as a separate feature, its all good:

I want the first member to stay squared and not be cut.  Any suggestions?  I have turned off corner treatments with no change.