Problem: ArcMap/ArcScene crash when constructing two large TINs consecutively
This problem is addressed in ArcGIS 8.1 Service Pack 1. See the Related Information section to download this pack.
ArcMap/ArcScene can crash if two large TINs (500,000+ nodes) are built consecutively in the same session.
This is a known issue.
Solution or Workaround
Build one TIN, exit the application, restart, and build the other TIN.