Original propellers break all the time, so we took some dimensions and created some build-on-demand propellers. 

These can be printed in PLA, but Nylon (P6) provides the best strength.  The propellers will require support when printing.  For best results, use a pin vise to clear the 2mm hole running through the center.  A1/A2 is compatible with the square shaft, B1/B2 is compatable with the regular pentagonal shaft.