To make the turbine blades you first have to mark or score a line down both sides of the thickest dowel. Now, mark a line down the long side of each plastic rectangle (80mmX320mm) 5mm from the edge. Along this line mark crosses at 30mm intervals. (This is so that the pins that you place down both sides of the dowel don't match up). Now, using a vice or glue, align the line on the plastic sheet and the line on the dowel. Hammer pins through the plastic into the dowel securing the two together. The easiest way to do this is to put the first and last pin in so you can align the plastic and the dowel easier.
Attach another plastic rectangle down the other side to form a triangle and glue the 2 plastic edges together using dichloromethane . Repeat this for the other 5 pieces of thick dowel.