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Although I know I shouldn't have used this single acting Martin truss rod I'm frugal and wanted to use it up.
My neck now has to much relief (.044) with no tension on the rod.
Any ideas on how a guy can straighten this out a bit?
thanks,
Peter

.044 non induced relief Exactly how are you measureing that?



personally I do not build any relief into the neck/fretboard.I actully induce just a tad of revers preloading before leveling, I level the fretboard on the neck/body befor fretting. Like I said with just a tad of tension on the rod in the back bow direction. not enough to bow the neck but enough to maintain loading on the rod. Then i level and fret. It seems to me that if you have relief pre built into the neck/fretboard or do not have pretension on the rod at Fb leveling then fret leveling would be a royal pain at best.

I set my action (sting clearance .052-.011 gauge 24.5" scale) at E.022"-e.011" at the first / E.088"-e.068" at the 12th then induce .002"-.004" additional string clearance at the 8th

Um... tighten the truss rod? What am I missing here? It's all strunged up, right?

_________________
Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

I guess you mean back bow? With that much back bow you gotta pull the frets and plane the board.

_________________
Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

You're going to have to jump back in to clarify what you mean by "uninduced" relief. Relief is the bow of the neck
toward the front of the guitar or in the direction of the string tension's force. If your neck is pulling away from the
direction that the strings' tension will cause the neck to bow, you're using the wrong terminology and are talking
about "back bow".

I'm assuming that you have measured that relief with a straight edge and have arrived at that .044" measurement
without string tension.....which would be the typically accepted source of relief induction.

That Martin rod is a good quality rod if it's one of the chromoly rods embedded in an aluminum channel and will
have absolutely no trouble pulling that .044" of relief out of the neck....even under string tension. I prefer a one way
rod and still use a design that is my own and is proprietary to my guitars. It employs a similar technology to that
of the Martin rods where the wider, more consistent channel distributes the load of adjustment very evenly
along the length of the neck's barrel. I just have mine built from better materials and to different dimensions.

String it up, set it up and adjust the truss rod accordingly. You should have no trouble at all bringing it down to
less than .005" if you like it that straight.

Regards,
Kevin Gallagher/Omega Guitars

I think he is saying tha strung up and with no tension on the rod he is getting .044" separation from the bottom of the strings to top of fret at somewhere around the 8th, this is an assumtion though. If he adds tension to the Martin style rod he can only induce more relief. The key helping here is knowing the string clearance he has at 1st and 12th. We only have part of the equation

with a capo on the 1st fret and string fretted on the 13th the measure from top of the fret to the bottom of the string is .044 at the 7th fret.
tightening the rod only serves to increase the bow.
Peter

Peter,
The one way rod that Martin uses and offers for sale enables adjustability only in the direction away from string tension.
This allows the strings to provide relief while the rod only provides resistance to it to straighten the neck out.

Your measurement of .044" at the 7th fret with the string spanning the crowns of the 1st and 13th frets may be a bit
excessive, but is by no means beyond the adjustment capabilities of that rod.

The .044" is presenting a great positive relief limit in any case. I doubt that you'll ever want it that high.

I'm not sure of you have the rod installed in reverse or upside down, but it should be working in the opposite manner
than you're describing. How many of these rods have you used in the past. Martin has used more than 500,000 of them
since I was there in the early 90s and they work to provide adjustment toward the back bow end of the relief swing. They
still use the same rod assembly today that they were using back then. I'm there about three times a month or so and see
them being installed in every guitar.

Regards,
Kevin Gallagher/Omega Guitars

It's a single action rod. It pulls the neck back == REMOVES relief. If you want to tighten a rod and ADD relief you'll be needing a dual action rod.

I'm thinking I must have installed it upside down , when I tighten the rod ( clockwise) I am increasing the amount of relief.
other than removing the fretboard do I have any options

Is it possible that, with that much relief, the rod cannot get going properly with the strings tensioned? I'm thinking if you untensioned the strings so the neck straightened, started tightening the rod (maybe pushing up on middle of the the neck) 'till inducing some backbow, THEN tensioned the strings, you might have the rod acting properly, against string tension. Just a thought.

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Dave
Milton, ON

I did try what you're suggesting to no avail.
I think I'm doomed

No, I don't think you are doomed. But I do think you are going to learn how to pull a fretboard. A thin, flexible pallet type knife and a heat source will get you there.

_________________
Aoibeann

I know that Martin had started using the new rods, but introduced them in certain models while using up
the single action rods that were on hand. There are still loads of those Gotoh rods in the neck assembly
department there.

I've tried a few of their new double action rods that were give to me while I was there last year, but didn't
like them and suggested that they go back to the old rods.

Regards,
Kevin Gallagher/Omega Guitars

piiman , its time to back up a bit, if you put the rod in backwards, you need to remove the fretboard , and rod and turn it around , a setback yes , doomed ? I dont think so ! I was worried about making that mistake, so I asked John Hall on the QT , just to reassure me I had the right idea ! you can fix it man ! Jody

Yup, your right Jody.I'll give it a whirl next week. I haven't done anything with it yet because I'm so bummed and embare assed
I've installed others, I just had a vapor lock

Peter

I removed and replaced the fretboard and truss rod, it went much better than I anticipated
thanks all for your help.
Peter

Way to go!

_________________
Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

_________________
Aoibeann