So I've routed a truss rod slot in a neck blank. It's a custom arc, designed to be adjusted at the body end. Stupidly I routed the slot prior to final thicknessing the neck, wich I subsequently thinned down on the rear instead of the fretboard side. The result is the truss rod is pretty deep, 17mm slot depth around the 5th fret. This will leave me with around 3mm of wood at the thinnest point. (20mm blank for a two piece neck). Is that enough wood, or is the neck scrap now? I know it should be thin, but 3mm is pretty damn skinny!