surface pattern triangulation problem

Hi there, I've been trying to achieve a structural triangulation on a surface by having diagonal line from top to bottom and reversing them to produce an intersection that produces almost a diamond like pattern.

however I have encountered a problem were at the end of each division along the surface I have the script randomly plots a line from the end of each division to the beginning of the next division, producing a weird diagonal straight line that is not on the surface but just floating. maybe the script will explain better