- Wider shaft to prevent flexing
Drive shaft secured at both ends to prevent vibration
Washout added to blades
Duct lengthened to allow air to accelerate
Thinner walls and shorter screws to save weight
Narrower gearbox to not obstruct air
Stators are now aerofoil sections
Seriously impressive project, might as well use it to propel a bike
But unless your nylon is higly CF/GF-filled, it is not that much stiffer than petg in my experience, so you'll still have problems with blades contacting the shroud at high RPMs I suspect. They might *survive* it though, but this is still not very nice...
Using CF/GF filled filament (not nessesarily nylon, CF petg works well according to my tests, to promote epoxy adhesion) and carefully gluing strips of uni CF to stiffen the construction over it will work, but balancing it would be a nightmare (I think it was already suggested).