The truss rod nut is completely seized on a Yamaha BB414 that i acquired recently. It's a regular hex nut placed at the heel. Took the neck off completely and clamped it into a back bow BUT even then to my shock the nut would still not give one bit in either direction. I tried to spray some anti rust into that little hole in the nut, left it upside down and waited a day but still nothing. I don't even know if it has rusted but that was the only reason i could see why it would be stuck. I have yet to try some penetrating oil. Anybody had a similar issue that they managed to fix or do i just have to live with not being able to adjust it? Please no "take it to a luthier" talk, don't bother.