Truss Rod Nut Problem - No it's not stripped.

Discussion in 'Hardware, Setup & Repair [BG]' started by bcbckr, Jul 23, 2020.

  1. bcbckr

    bcbckr Supporting Member

    Feb 27, 2019
    Calgary Canada
    I recently bought a 2017 MIM P-Bass for a reasonably good price. I started trying some different strings on it which lead me to adjusting the truss rod. When I inserted the hex wrench into the truss rod nut, it felt a little mushy so I stopped immediately. I used a flashlight to check out the hex head and sure enough, the head was starting to strip. I stopped immediately, and ordered a new part.

    The part arrived, so I carefully removed the old truss rod nut, and I saw that I had made a good call - the head was just at that point where is could have become a problem. The threads of the old nut are in great condition, it was only the head that was the problem.

    Looking down at the end of the truss rod, I could see that it was a little off center. Not a lot but just enough that the new nut will not engage with the threads of the truss rod. I confirmed that my new nut was the correct part. I even reinserted the old nut as a test to see if it would engage and it would not.

    I was wondering if anyone had any suggestions on how I might get the nut to engage the the threads on the truss rod. I don't want to do anything that might damage the threads.
  2. Ross W. Lovell

    Ross W. Lovell

    Oct 31, 2015

    Remove the nut.

    Make sure no threads are damaged.

    Replace the nut.
  3. bcbckr

    bcbckr Supporting Member

    Feb 27, 2019
    Calgary Canada

    I've removed the nut. I've made sure no threads are damaged. It's the "replace the nut" part that isn't working. The end of the truss rod that is the problem. It's off center and leaning to 7 o'clock. (see diagram below)
  4. BassFishingInAmerica


    Jul 24, 2014
    Have you tried putting some tension on the neck as you try to thread the new nut? Try to direct the truss rod into position.
    MCF, Lownote38, pcake and 2 others like this.
  5. bcbckr

    bcbckr Supporting Member

    Feb 27, 2019
    Calgary Canada
    Great suggestion. I'll give it a shot.
  6. This. Move the neck around a little. It should take the tension off enough to get the nut started.
  7. bcbckr

    bcbckr Supporting Member

    Feb 27, 2019
    Calgary Canada
    Thanks guys. It worked. I ended up clamping the neck to my workbench and gently flexing the the neck while turning the new nut until it caught. I totally appreciate the help.
    MCF, Fender4Me, Lownote38 and 4 others like this.
  8. Bruce Johnson

    Bruce Johnson Gold Supporting Member Commercial User

    Feb 4, 2011
    Fillmore, CA
    Professional Luthier
    I'm glad to see that you got it on there okay, but for everyone's reference:

    That's a real common problem with Fenders. You remove the truss rod nut and the end of the truss rod springs to one side a little bit. It looks like you can't get the nut back on there. But it isn't fixed hard in that position, just sprung there. If you stick a little screwdriver down in there, you'll see that the end of the rod can easily be pushed sideways.

    The simplest way to get the nut re-engaged is to slip the nut down into the hole, with the Allen wrench engaged in the hex socket. Push it down in until you feel it contact the end of the rod. Push straight in on the Allen wrench, while turning it slowly. That's usually enough to kick the end of the rod into the center of the threaded hole in the nut. If not, put a light hammer tap on the end of the Allen wrench. You should feel the nut pop onto the end of the rod. Then turn the wrench gently clockwise until you feel the threads engage. Or, turn it lightly counterclockwise until you feel the threads "click" into engagement, then turn it clockwise.
    Joshua and Gilmourisgod like this.
  9. bcbckr

    bcbckr Supporting Member

    Feb 27, 2019
    Calgary Canada
    Thanks for this Bruce. I did try to move the end of the rod with a screwdriver but it sprung back to it's seven o'clock position. I didn't want to poke around with a screwdriver because I was afraid of damaging the threads on the rod. I also tried "encourage" the rod to mate with the nut by tapping while turning no luck with that either. When I pulled the nut out after tapping while turning, the nut was scored from contact with the rod indicating that it the rod wasn't moving laterally. To be fair, the truss rod nut is designed to push the rod to the center - the end of the nut is concave (dished-out) before the threads start. The idea is that when the rod touches the inside of the nut, the it is deflected toward the center. In my case, that deflection wasn't happening.

    It really blew me away how quickly everyone responded, that the suggestions were all constructive, and led to a positive outcome 81 minutes after my first post.
    (edited for clarity)
    Last edited: Jul 24, 2020
    Joshua and MCF like this.

Share This Page