Step 1: PVC Tube
Take a pvc tube with about 10cm diameter and about 50cm length.
Step 2: Cutting in Two
Cut the whole tube into 2 (on the half) so as to take 2 semicircular pieces.
Step 3: Cutting in 4
Cut the 2 semicircular pieces on the half so as to have 4 long semicircular pieces.
Step 4: Cut the Propeller
Now, draw and cut the propeller as you can see on the image.
Step 5: Watch the Blueprint
You can see the draw so as to held yourself for better results.
Step 6: Finishing
In the end, cut a circular piece of wood or steel on where the propeller will be placed. Use screws and some glue to make it stronger.