This is actually where the tape would be superior to any kind of key locking, as the locking wouldn’t allow for as much tuning. Tuning is one of the benefits of a take apart system. This magnet system without a locking device, offers greater tuning than other options I know of, at least for tuning out vibe.
Also the key locking systems, would be be extra difficult to pull off in a way that would allow an easy swapping out of axles, and without introducing vibe.
The more I think about it, the more I’m embracing the idea of the design as it is, and using tape if necessary.
Another cool prospect with this design is the possibility of plastic halves to go with the wood axle!