ideally, your joint is good enough that no real pressure is needed to join the wing halves. I'd recommend epoxy for this. With a good joint and the wingtips supported, tape should be all you need to hold things in position. After this is dry, you're probably best off to apply a strip of fiberglass cloth around the outside using finishing resin or CA with good ventilation. Keep in mind the epoxy you're using to stick stuff together is not finishing resin..... One of the big diffences between this stuff and finishing resin is that finishing resin is sandable and typically is much runnier (wets the cloth better). You can use your non-finishing resin epoxy for the fiberglassing... Add some alcohol to thin & don't plan on sanding it!! Or use CA and don't knock yourself out with the fumes.