Just an observation here, if tip plates are employed to reduce tip vortexes and these vortexes are more prevalent towards any trailing edge due to directional travel then why not simply install them only on the rear most part - the moving elevator only?
Please see the preceding post, there is a functional angled gap built into the model between the tip plate and the elevator, and at that gap the air would accelerate through, create the very vortex the plate seeks to avoid thus the plate as installed becomes partially redundant.
Better to use a half chord plate fixed only onto the elevators tip that travels through the same range range of deflection.
Doing this would make the elevators deflection visible to the flier as both the tip and elevator would move as one, cut down on drag evidenced by the slot or 'angled gap', stiffen the moving part and be lighter to construct.
Thoughts?