hi olle.

If you zoom in on the bevels at the end of each blade there appears to be a crossover of the broad edge of the bevel i.e. the bevel is not a flat plane. One corner appears sharp and the other appears rounded over. The bevel is not properly formed.

I used a straight line to trim of the ends of the blades just above and below the cylinder and then used loft and join to reform the blades as solids(test1.png). The boolean difference operation then worked(test2.png).


Hope this helps.

Cheers
Mal