Boron is one of the stiffest materials available to strengthen model parts subject to extreme bending loads. Run some full-strength model glue along the boron between your fingers, or use a boron glue applicator (see Tools section). Let dry and apply to the model with acetone on a small brush. Keep it in tension with a rubber band CyA'd to one end, stretched and held down with tape to the building board. Glue the ends down well; boron ends and pieces shorter than one inch can penetrate the skin before buckling and usually break off at the surface, making removal difficult.
Boron is not used for SO or TSA models! It can be dangerous.