Sprink. A pictures worth a thousand words
Main spar is carbon and goes though both wings and fuzz. The 6mm carbon you can see at front and back are bonded in the fuzz with just 15mm sticking out thes two set the incidance spot-on. Each wing has a 300mm outer tube and same for the fuzz (150mm)
the wings are fed onto the live inner tube one each side and tie wrapped inside the fuzz.
As graham has already said you could use a spring ay Sprink
Make any sense now?