Propeller Design for the Remote Control Submarine
Version 1
This was my first attempt at making a propeller and like many first attempts mistakes were made. The propeller was very tall and did not pump water in the axial direction during testing. Rather, it flung the water out to the sides like a centrifuge.
Version 2
This version was slightly shorter and utilized a greater pitch in the blades. In reflection this looks more like an auger blade instead of a propeller! Similar to Version 2 this propeller performed poorly
Version 3
At this point I had been studying the propellers used on outboard motors. So I reduced the overall height of the propeller drastically. You can also see that I added a center lug for mounting to the drive shaft. This propeller actually performed very well! However, I soon discovered that I was overloading the 1000 KV brushless motor.
Version 4
After testing the Version 3 propeller I discovered that having more blade surface area is not always a good thing. This propeller only has 2 blades and they are very thin. This is because I was trying to reduce the load on the motor in an effort to keep it as well as the Electronic Speed Controller (ESC) from overheating in the enclosed submarine.