I'm planning to start building the Vampyr flying wing soon, and due to limited space (it's a garage project for now) I'd like to make the 24' wing in two sections, joined at the center. I can calculate the size of the connecting fittings/straps and bolts, but I'm wondering about drilling through the spar cap. The cap dimensions are 1 3/16" wide by 1 9/16" deep. Are there any guidelines for the size hole that can be put in a spar cap without compromising its strength? Also, would it make sense to add a solid piece inside the spar at the joint for extra support or is that just overkill if the fittings and bolts dimensions are calculated correctly?