1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  

Adjusting truss rod under tension.

Discussion in 'Hardware, Setup & Repair [BG]' started by xshawnxearthx, Oct 26, 2013.

  1. xshawnxearthx


    Aug 23, 2004
    new jersey
    Will this screw up the truss rod/neck/graphite re-enforcement rods?

    Im trying to settle an argument. I had a tech tell me last night that it's ok, but I've always been told that you need to remove tension before making adjustments.
  2. BillyRay

    BillyRay Supporting Member

    Jan 20, 2008
    I'm not a luthier, let alone a tech. I'm just a guy who does his own setups.

    I always reduce tension and induce some backbow via mechanical force when tightening the truss rod (I do the opposite when the rod is too tight): the nut is easier to turn and there's less chance of chewing it up. I also remove the neck on some basses.
  3. Itzayana


    Aug 15, 2012
    Oakland Ca
    I use a pneumatic lug nut wrench on truss rods that are a little hard to turn. Doesn't matter which way you turn them. Just squeeze the trigger and ler her rip until it spins freely.
  4. FunkHead

    FunkHead Supporting Member

    Mar 10, 2007
    I truly hope you are joking. @OP Take the tension off the neck. There's no reason not to. First loosen the strings, Support the body and push lightly back on the headstock.
  5. Musiclogic

    Musiclogic Commercial User

    Aug 6, 2005
    Southwest Michigan
    Owner/Builder: HJC Customs USA, The Cool Lute, C G O
    Commonly known as an "impact".....lmfao
  6. Ric5

    Ric5 Supporting Member Commercial User

    Jan 29, 2008
    I grow organic carrots and they are not for sale
    Yep ... your bass is toast ... you will need a new neck ... and probably you ruined the pickups and bridge as well ... also the strap is also damaged and while we are at it check you amp for damage as well.



    The only basses I know of that you need to loosen strings are the old Rickenbackers model 4001 1985 and earlier. On those basses you loosen the strings, loosen the nuts at the end of the rods, then move the neck then retighten the rods and then tune it up to check if the neck is adjusted correctly. Repeat until done. If done incorrectly the neck is damaged.

    Pretty much all other basses had rods that you simple adjust and they move the neck. However sometimes a neck can be problematic. In that case I leave the strings on but I push the neck into backbow and then turn the rod. This may require a second set of hands.
  7. nashman


    Feb 11, 2011
    I also think it's a good idea to reduce tension via mechanical force first. Use the truss rod to hold the neck in place vs. using it to force the neck to move - esp. when tightening.
  8. FunkHead

    FunkHead Supporting Member

    Mar 10, 2007
    Well said. Why tempt fate?
  9. Ric5

    Ric5 Supporting Member Commercial User

    Jan 29, 2008
    I grow organic carrots and they are not for sale
    I find that I often have to reduce tension on the strings just to get the allen wrench in the hole in the headstock on some basses. Other than that most basses can take a 1/4 turn of the truss rod without a problem.
  10. Itzayana


    Aug 15, 2012
    Oakland Ca
    For me even a 1/4 turn seems like a lot.
    I usually turn maybe only 1/8 at most. Then play it for a day or two and then another 1/8 (or less) if needed.
    I always plug the bass into my Peterson Strobe. Tune to pitch (checking harmonics), then make the 1/8 turn truss rod adjustment and watch the pitch change. This gives me a sense of how much adjustment was actually made with the 1/8 turn. I do not loosen the strings first. Then I re-tune and play the instrument for a day or two as I said to let everything settle in before deciding if it need further adjustment.
  11. Itzayana


    Aug 15, 2012
    Oakland Ca
    PS; After truss rod adjustments have been made and I am happy with the relief on the fingerboard. I re-set the intonation as it will have changed slightly. If you have a really accurate tuner (like a Peterson Strobe) you will see this when you check all the harmonic positions. Adjusting the bridge pole positions is always (for me anyway) the very last step.
    This is critically important for players who use the entire length of the fingerboard. Not so much for players who like to stay below the 7th fret.
  12. Zooberwerx

    Zooberwerx Gold Supporting Member

    Dec 21, 2002
    Virginia Beach, VA
    Unless I encounter an inordinate amount of resistance, I make adjustments with the strings to pitch. When in doubt, I will loosen string tension and use some elbow grease to flex the neck while addressing the truss rod. Heck, I have one particular bass (dual-acting rod, 3 mm) that I remove the neck to get a better "angle of attack". You strip one of those and you're SOL.

  13. xshawnxearthx


    Aug 23, 2004
    new jersey
    Ok, so not terrible to have it under tension. thanks guys!
  14. JustForSport


    Nov 17, 2011
    Trussrod threads are not pre-lubed and unless it's the kind with a nut to turn, there's usually no way to lube the threads.
    Turning under tension may well work fine- for a while.
    Most frozen or stripped trussrods likely worked well until they got tight and the threads, nut or socket stripped (or the rod broke).
    Best to release some of the tension mechanically and be kinder to the threads than to deal with the consequences later.
  15. Hapa


    Apr 21, 2011
    Tustin, CA
    The advice of not touching your truss rod under tension stems from the old days of acoustics. When necks simply did not have enough stiffness to hold the tension of the strings and were only kept straight from the truss rod lowering the amount of relief when all 6 strings were pulling from the top damage could happen. The neck would bow immediately raising the angle at which the strings came off the bridge pulling up on the top. That would/could flex the braces loose, causing more lift on the top, eventual catastrophic failure.
    This would happen on single action one way compression style truss rods - relative tension in one direction .
    This is why in general musicians were told by luthier's, "Don't touch the rod" Gibsons were like this for a long time. Rickenbacker too.
    Most of the rods now days are two way, single action - Keep constant tension but one way. The really nice rods are two way double - keep constant tension in both positive and negative relief.

    It is perfectly fine to adjust the rod under tension on a modern bass, if not ideal since set up needs fine adjustment under tension to be accurate. The same principle applies to fingerboard leveling/ fret leveling... under tension is the most accurate way.

    If you are not sure about what kind of rod you have, sure take some tension off. But the strings under tension will make the neck act differently than when not. That being said even with the old style rods adding relief is still ok with the strings under tension on a bass there is no floating top to pull on. Tuning your strings after the fact is default since one is slightly adding scale length and tension.

    Something to be aware of: The nut over a rod style...adjusting with a socket of some sort (gibsons) that are directly on wood can compress wood fibers if it is already wrenched down all the way. Especially over time the neck bends the truss rod out of effective range and one needs to cut more threads into the rod. Other wise like ^Justforsport said you can break off the threaded end on the rod/nut and have a lot of repair to make it right again.
  16. JustForSport


    Nov 17, 2011
  17. I have never adjusted a truss rod that COULD be adjusted with the strings at tension any other way. I just pop off the truss rod cover, adjust and re-install the truss rod cover. But I've never had any major truss rod or neck problems - those might well make it desirable to remove the strings and clamp or pre-stress the neck before adjusting.

    I do have a 1963 P with a 1972 neck which has the bottom-neck adjustment, but I've only had to adjust it once in 40 years.
  18. dStar


    Mar 1, 2012
    From the Fender Manual:

    "Caution: Because of the amount of string tension on the neck, you should loosen the strings before adjusting the truss rod. After the adjustment is made, re-tune the strings and re-check the gap with the feeler gauge."
    bass nitro likes this.
  19. I've never actually adjusted a truss rod without tension. Just don't go crazy. Make quarter turns at a time and let the bass sit for a while between turns.
  20. Old habit to prevent stripping: with strings tuned, when changing truss rod tension, I preload the neck by bending it to take pressure off the threads, turn the nut, release and check relief.

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.