40mm fan blades

After I broke two 40mm fans (Geeetech) by crashing the extruder against the end-stop I decided to print a replacement for the broken blades. Great, 5€ are saved. It is always good to have emergency blades if they are required for operation of the printer.

The dimensions are the same as the fan blades designed by kj6epl (http://www.thingiverse.com/thing:36223) except for the outer diameter. I use 36mm and kj6epl uses 0.7in (35,56mm). There you can also find a very detailed description how to r