I used FreeCAD to make all of the 3D designs. I primarily used the Part Design, Part and Mesh workbenches. My workflow was to make sketches, and pad, pocket or revolve in Part Design, then move to Part for boolean operations (for interlocking parts), then export the shape as a mesh.

I redesigned the teeth, solenoids, and valves for the siphon pump. I used a clear acrylic shell, because I am still focused on placement and the relationships between the teeth, solenoid and valve. Once I know their placement, they will be integrated into the shells.