The Tri Tool does not have a 60 degree angle, so it will not work for this pattern. Here's a description of how that tool is supposed to be used -
http://softexpressions.com/software/...zQuilt.php#tri
Basically, the Tri Tool has the same length HEIGHT and BASE. The 3 sides are not the same (so not equilateral) and so the angles are not 60 degrees.