I decided to take a novel approach to countersinking the spar holes that accommodate the wing access plate – I followed Van’s directions. That meant countersinking rivet holes, riveting the nutplates to the spar, then countersinking the access plate screw holes. I experienced none of the chattering or other problems reported by other builders. I think the key here is using a low-speed, high-torque drill to drive the countersink – a cordless drill works fine.

While getting ready to countersink those additional wing spar nutplates, I noticed that most of wing spar doubler plate (or “waffle” plate, as Van’s calls it) holes were somewhat oversize. Here’s a number #30 rivet in one of them.

Spacers done

I fired off some pictures and questions to Van’s. More to follow…