Pretty basic question; looking for confirmation/correction re. truss rod adjustment

Discussion in 'Acoustic Heaven' started by SixStringSlinger, May 11, 2020.

  1. SixStringSlinger

    SixStringSlinger Friend of Leo's Silver Supporter

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    I have an old Goya acoustic I really like, but has a bit too much curve to the neck. The truss rod adjustment is at what I would call the neck heel on an electric, just inside the sound hole. It's the only guitar I have with the truss rod adjustment in this location.

    Which way do I turn it in order to straighten out the neck? I'm thinking clockwise, and maybe I'm overthinking this, but for some reason I'm not confident in my conclusion.

    Also, it's a little tough to turn, so I don't want to put any force into/incur any risk by turning it the wrong way.
     
  2. 8barlouie

    8barlouie Friend of Leo's Silver Supporter

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    Turn it clockwise to straighten the neck. Like you already stated, don’t over tighten.
     
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  3. Peegoo

    Peegoo Friend of Leo's

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    If it has not been turned in years, loosen it first. A quarter turn is good. Then tighten it.
     
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  4. SixStringSlinger

    SixStringSlinger Friend of Leo's Silver Supporter

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    Thank you!

    What's the logic here?
     
  5. schmee

    schmee Doctor of Teleocity Silver Supporter

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    You dont say which way the neck is curved?. If the neck is down from the strings in the middle, you need to turn the truss rod clockwise. Loosen the string s bit first.
     
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  6. SixStringSlinger

    SixStringSlinger Friend of Leo's Silver Supporter

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    Yes, the fretboard and strings are too far from each other at the middle of the neck.
     
  7. Peegoo

    Peegoo Friend of Leo's

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    To free up the nut on the rod; sitting for years, corrosion can chemically/partially 'weld' the parts together. Loosening it frees it up better as tension comes off the rod. If you simply turn clockwise, the rod can rotate with the nut.
     
  8. Freeman Keller

    Freeman Keller Friend of Leo's

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    I suggest measuring the amount of relief that it has right now, then go very slowly as you try to flatten it out. Usually on an old guitar anything less that 0.010 inch is pretty acceptable. As others have said, turn CW when looking at the adjuster, 1/8 to no more than 1/4 turn at a time. Let it settle for a day, check the relief, then give it a bit more if necessary. Also make sure you have the correct wrench - various makers have used different sizes, both imperial and metric.

    There may be some other issues with an old guitar like that - most frequently the neck angle. I make a point of checking everything to do with geometry before I make any adjustments since they are interrelated.
     
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  9. SixStringSlinger

    SixStringSlinger Friend of Leo's Silver Supporter

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    I see, so you're loosening it up before putting it to work. Thank you.
     
  10. SixStringSlinger

    SixStringSlinger Friend of Leo's Silver Supporter

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    I haven't measured the relief in a while, so I can't give a number, but it's in the realm of "this is difficult to play" more than "this is not perfect". The string height at the nut feels good, and I recently shaved the saddle down a bit which improved the height at the high end of the fretboard. The only thing giving me trouble now is the middle.

    I'm not expecting perfection, but I think this guitar has room for improvement.
     
  11. Freeman Keller

    Freeman Keller Friend of Leo's

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    If it helps, I did a little write up about how I approach setting up any guitar

    https://www.tdpri.com/threads/basic-setup.952636/

    I'll add that most acoustic guitars with sound hole adjustment truss rods have one of two styles of rods - either the Martin U channel single acting rod or the newer double acting rods. If the head of the allen nut is real close to the sound hole it is probably the U channel kind. Both are much safer from freezing up and breaking than the old threaded rods with nuts in the head, but it still doesn't hurt to back them off a quarter turn before tightening.
     
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  12. Freeman Keller

    Freeman Keller Friend of Leo's

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    Here is a very rough measurement. A typical business card is about 10 thousand thick. Put a capo on the first fret and hold a string down at the body joint (14th fret usually). If you can barely get one card between the string and the 7th fret your relief is more or less OK. Two cards or more is too much.

    You can also use the cards to check other things - I like around 20 thou or a bit less between the strings and first fret, that is two cards. I like 60 or so thou on the high E string and about 90 on the low, that is a small stack of 6 to 9 cards. Automotive feeler gauges are much better and I would not work on a guitar without real measuring tools, but for a quick check the cards work fine.
     
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  13. fenderchamp

    fenderchamp Tele-Afflicted Silver Supporter

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    I like to loosen up the strings before turning the nut.
     
  14. Dreadnut

    Dreadnut Tele-Afflicted

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    I agree with Freeman's approach. Remember, a guitar neck has camber like a ski, the truss rod adjusts the amount of camber.

    At any rate, measure twice, and adjust in small increments. A drop of mineral oil on the truss nut previous to adjusting might help as well.
     
  15. tubegeek

    tubegeek Tele-Afflicted

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    I can certainly relate to this portion of this thread.
     
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  16. Buckocaster51

    Buckocaster51 Super Moderator Staff Member Ad Free Member

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  17. fenderchamp

    fenderchamp Tele-Afflicted Silver Supporter

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  18. SixStringSlinger

    SixStringSlinger Friend of Leo's Silver Supporter

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    Thanks for all the replies and resources. I turned my truss rod about a quarter turn total (maybe a touch more) in small increments. I'm not sure it did much, but whatever it did plus a little more shaving of the saddle have it playing a little more enjoyably. It probably doesn't hurt that I was playing it more during this time, either :rolleyes:
     
  19. fenderchamp

    fenderchamp Tele-Afflicted Silver Supporter

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    playing it more during this time<<<<<<<<<<<<<<< YES! THAT!!!!! [​IMG]
     
  20. ASATKat

    ASATKat Friend of Leo's

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    The two key words you said were "old" and "curve".

    A third dreaded word is "memory".

    Get what I'm suggesting?

    Good luck. Maybe think slide?
     
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