Since I’ve been exploring various pump options, of course it occurred to me to make one from scratch. I have a pretty cool prototype in the works using a 12.5″ boat propeller as an impeller, cut down to fit inside a 12″ PVC pipe. But that will take a week or two to have anything to show.

In the meantime, I became curious about making my own propeller. A quick Google search shows some 3D printed toy boat propellers, so I figured it was worth a try. It took me about 3 hours to design it on FreeCAD:

It is designed to fit inside a 5″ PVC pipe, which is the largest my printer can print in one go. But the 3D printer is running now on a 3/5 scale prototype print. (It might fit in a 3″ PVC pipe.)