This single blog post could never explain even a hundredth of the thought and work that went into the thruster. Months and months of design and redesign and prototyping resulted in what you see here. This is the first thruster with the outer tube of the housing removed. The two black things on either end are delrin end caps with various features machined into them. The gold thing is an R/C airplane brushless motor, the one with the lowest kV rating I could find in this size class (basically that means it's meant to turn slowly). It drives a 4:1 belt drive reduction using a GT2 timing belt. Then there's a magnetic coupling that transfers the power through the sealed delrin end cap to the propeller which would be to the left if it were present in this picture.
This thruster has about 25 days of run-time on it without any significant, noticeable wear. Not saying that's enough for 100% confidence in the design, but it's a good start.