The prop and duct is 3d printed in PLA on a 500$ 3d printer. The picture is from an initial assembly, prop and duct are now Sanded smooth and epoxy coated. The prop design on the picture is not optimized at all, we drew it with very limites knowledge of props and no calculations, will start with a thorough theoretic optimization combined with hands on testing now!
Dont know any good books. We just read around on the internet, much bad information, but some gold nuggets here and there, research papers are mainly a good source. It will be interesting to learn more about prop design. Most of the litterature we find is based on large vessels, but we think It translates pretty well to our use.