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I have a Chet Atlins (SST?) on the bench at the moment. The Truss Rod refuses to stay put. I've been trying to set it up and when the rod has some tension, it plays great. However, I will sit it aside to go work on other guitars and when I go back and check it, the neck has a bunch of relief that wasn't there only a couple hours before. The humidity today is much higher than it was yesterday and it is still going into a pretty good forward bow. I'm afraid that when the weather dries up the customer will be complaining of super high action.

Does this ring any bells with the folks here? The only other time I saw this was on an ES335 that I had years ago. I sent it to Gibson for repair and they just sent me a new one. The customer has owned this guitar for close to 20 years and I don't think he would want a new one due to the fact that this one has been played in considerably. Not to mention it's super vibey with all the checking in the finish, dings, dents, etc.

I guess I'm just a little stumped. What would you do?


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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

My guess is the other end of the truss rod has come loose from the lug meant to keep it from moving. Pull the fingerboard, and see...

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"Act your age, not your shoe size" - Prince

Could the washer & nut be crushing into the neck?

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

If you have a buddy that is in health care sneak in and XRay it. I have done that a lot to look at a neck joint with which I am not familiar with or a truss rod issue. It is usually pretty obvious.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Like Brian said.

But-tighten the rod to make a back bow.
Then see if it lets go again.

Mike

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Mike Collins

I've seen a Gibson adjusting nut have enough slop that it wouldn't stay tight. Tighten the nut to adjust the neck and then using the end of your calipers measure the distance from the nut to the end of the truss rod. Measure again when the relief reappears; compare readings.

No access to an X-Ray machine unfortunately.


Probably. That is a very common scenario. It's almost 20 years old though. I feel like whatever movement, give, etc. that is going to happen in the wood has happened by this point.

I wonder if some kind of a split washer may keep it in place? Hmm...

I'll be back.



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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

You can't (or at least shouldn't) do anything with it until you've reliably determined where the source of the problem lies. The nut washer could be compressing in to the wood at the adjustment nut. The rod anchor could be compressing wood from the other end. These problems usually happen in much more easily observable real-time crushing as you adjust rather than over hours, but I suppose it's possible for there to be such a lag.

Set the neck dead straight, or to a point easily and reliably measurable. Take good note or photos of the truss rod nut/washer, and measurements as mentioned above. Check again the following day, or give a light flex back on the neck to see if any compression occurs in a way you can observe, and at which end.

If it's truly slipping, you have to accurately evaluate where and why before going any further.

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Eschew obfuscation, espouse elucidation.

I realize I forgot to reply with the conclusion to this repair.

I put a small lock washer behind the adjustment nut. Wasn't expecting it to work but it did the trick. It was wood compression I guess.


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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."