Equilateral Triangle with a linear extruded frame

looking to make a wireframe structure with interchangeable text panels. proud of using trig and rounded corners (thx, Mathgrrl!)

.2 layer PLA. 10% infil (no supports)
LOTS of separation. (old? filament, supports, maybe?)
first step towards real designs.

Thanks to:
-OpenScadTutorial.org for all the preliminary instructions.
-Mathgrrl for the cointrap rounded corners solution.
http://makerhome.blogspot.com/2013_08_27_archive.html
-Wikipedia for helping me refresh trig memories w