先用硬纸包住塑料桨叶,这样就拓出了桨叶气动外形,如果纸不保形可以涂一层胶水。
桨叶气动外形:
https://www.google.com/search?q=airplane+propeller+design&safe=strict&tbm=isch&tbs=rimg:CQyGSAYotpsDIjhijue6T32mSzv7XpGUmF5MYPkCKSyv8qrY_125RMMZHl_1ilRkxL-XOtPhd7bbEW5NQ8LffWEqgd2CoSCWKO57pPfaZLESE1MNrV8xzzKhIJO_1tekZSYXkwRIzEg5yPOUoEqEglg-QIpLK_1yqhFa1Oxzm9IZeyoSCdj_1blEwxkeXEQr8IfEjNg91KhIJ-KVGTEv5c60RgiwiUH9DocwqEgk-F3ttsRbk1BFV709ToMwjGyoSCTwt99YSqB3YEevgJG80wi4P&tbo=u&sa=X&ved=0ahUKEwjlzfjJ0bDYAhUCRN8KHZLrAI4Q9C8IHg&biw=1280&bih=726&dpr=1#imgrc=na4ed-CuFqF01M: