I've now exchanged the suspect blind nut for one from my spares box, but the one I removed looks ok to me. I tried fitting a different bolt into the original nut (see pic) and it doesn't seem to bind, or to have done any damage to the thread. Bearning in mind that once I'd fitted the wing in place, the wing bolt stayed-put, as I don't remove the wings from my models between flying sessions. So I guess this means that I damaged the bolt just by flying my Twist hard . . . . and as I asked earlier: Has this happened to anyone else?

Tony