RE: tail feathers to scale by using either dowels or aluminum tubing
Cub man, go for it in ali tube for the outlines, but use dowel for the elevator leading edge and the tailplane hinge spar, works a treat. At the inboard ends of the tube, where they plug into the fuselage, they need strengthening with a sleeve of tube or such like. Epoxy or CA work very well to glue aluminium to balsa and hardwoods. I had the same structure on a 1/4 Cub, 1/3 Baby Great Lakes, 1/3 Tiger Moth and an under construction 1/3 L4 Cub, which also has light gauge steel tube for the cabin area of the fuselage. Using dowel for the whole structure would be quite heavy, also hard to do with the curves of the Piper tail surfaces. The tubes can be bend round an MDF, or chipboard former, or something similar, with the former on the inside, or the tube can be easily distorted. When bending the tube around the former, always pull it round with a bit of tension, this will stop the tube from kinking, and will result in a nice smooth even curve. When covering, it may be neccessary to wrap the tube with fabric (like they do on the full size) to help the fabric adhere to the tube structure.
On smaller structures, say 1/6 scale, outlines can be made using ' basketry cane', which is strong but flexible, and can be bend round shapes (about 40mm radius) without breaking.
Hope this helps, Ian.