have had a muck around again with the design of the blade and went with a simpler 8 tip arrangement. instead of fins for air flow i was thinking of getting a "rake" type plate that is basically a full width plate with fingers cut out that would go between the blades and span from the front roller to the shaft of the cutter. this would be to direct any debris into the catcher.

going a more basic assembly method as well with these blades by simply sliding each blade onto the shaft, spacing and welding each one. so removal of blades would mean grinding them all off. painful but just would like to get something working as summer thatching is almost happening here(i know its still winter!)

here is some pics(virtual anyway)
[Linked Image]
[Linked Image]