На сайте c 12.03.2013
Сообщений: 1056
Ростов-на-Дону
Первая ссылка в гугле.
Did you know that you can select the borders of Polygon groups, Smoothing Groups, or Materials groups? Switch to Edge Selection mode, then go to Menu->Select->Show Model Groups, then double click on the name of the group you want to their border be selected.