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Old 04-11-2018, 02:48 PM
calstang66 calstang66 is offline
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Default Used & Neck Reset Evalutation

Buying a used, 15 yr old guitar, 22 yr old guitar....
  1. Would this be about accurate, that for a "New", quality guitar, the neck should not need to be reset, on average, for probably at least 20 years?
  2. Would loosening the strings every night help to reduce neck warp and extend the time before a neck reset is needed?
  3. How about always practicing with tuning down half step to D#?
  4. I think my luthier says a neck reset would cost about $350 for most guitars, but isn't there a major issue with refinishing the area, laquer, gloss, matching it well?
  5. So let's say I'm considering a used guitar, built in 1994, the saddle height is OK like medium appearing that some sanding has occured on its' bottom, adequate string angle off the back of the saddle, the action is great, kind of low, and with these assessments, I can't be certain that the neck is ok, because I did not perform the "straight edge test". So now, I do that and the straight edge hits the bridge a quarter inch below the top of the bridge. I am correct to say that the guitar is going to play well for the present, and the guitar may be fine for a long time, but, it also, "might" need a neck reset in 3 to 5 years, due to that quarter inch?
  6. But wait, is it true that I can get rid of that quarter inch (thus causing this guitar to "pass" the straight edge test) by just tightening the truss rod. And there's no way to know how many times or how many turns, the truss rod has been adjusted, until, it won't tighten anymore.
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  #2  
Old 04-11-2018, 03:54 PM
Rodger Knox Rodger Knox is offline
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If your not building the guitar, just forget about the straightedge test.

If the relief (adjusted by the truss rod) is OK (0.003" to 0.008"), the action is to your liking, the string height above the top just in front of the bridge is OK (7/16" to 9/16"), and there's adequate saddle showing above the bridge (more than 1/16"), then the neck angle is fine.

In other words, if the guitar can be set up to play without sanding down the saddle beyond the above guidelines, the neck is OK.

The straightedge test is done without string tension, and the neck adjusted to be dead flat, so that the straightedge touches every fret up to the 12th or 14th, beyond that there can be small gaps (called fallaway).

The straightedge test is useful when initially setting the neck, because you can't put strings on until the neck is on, and when resetting the neck to evaluate how much change is needed initially and to monitor the progress as the work is done. That's really the only time it's useful.

If your not building the guitar, or resetting the neck yourself, just forget about the straightedge test.

edit: I forgot to answer your questions
1.That's not exactly true, but probably close enough. Some guitars may need a reset in just a few years, others never will. Wood varies.
2. Yes, but that's hard on strings, so probably not worth the effort unless it will be a month or two before it's played again.
3. Yes, and so will lighter strings, but it may not sound as good.
4. The $350 probably covers finish repairs.
5. You CAN be certain the neck is OK without the straightedge test.
6. No, that's one reason the neck needs to be adjusted dead flat to use the straightedge test.
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Last edited by Rodger Knox; 04-11-2018 at 04:14 PM.
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Old 04-11-2018, 04:05 PM
charles Tauber charles Tauber is offline
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Respectfully, you've been reading too much on the internet.

Let's start at the beginning. Martin-style guitars aim to have a design height of a 1/2" vertical distance from the surface of the top to the bottom of the strings at the bridge. This 1/2" height must be achieved while the string height at the 12th fret is "suitable" - a common value is about 3/32" - there is sufficient break angle of the string over the saddle (i.e. sufficient saddle protruding from the top of the bridge: 1/16" minimum, 3/16" maximum is preferred) and while the neck has an appropriate amount of relief - common values are between about .003" and .01".

When a new martin-style guitar leaves the factory, it should have been made/adjusted to accomplish the above. Some achieve it more closely than others. In some new instruments, the string height at the 12th fret is too high and there isn't enough saddle protruding from the bridge to lower the strings sufficiently while maintaining an adequate break angle. In some new instruments, the neck bows more than desirable and a simple truss rod adjustment might be all that is necessary to bring it back to the design targets. In some cases, an overly thick bridge can be thinned to allow further break angle. As the saddle is lowered, the string height at the bridge lowers from the design value of 1/2". In some instruments lowering the vertical distance can result in loss of volume and/or tone. In some of these cases - seemingly an increasing number - the bridge can't be thinned and there is insufficient break angle. The remedy is to correct the angle the neck makes with the body: a neck reset.

Many/most guitars progressively, permanently deform under extended periods of string tension. The deformation is that the top of the instrument "folds" into the sound hole, carrying the neck with it. As this occurs, over time, the change in geometry of the instrument results in the string height at the 12th fret progressively increasing. The usual remedy in dovetail/glued neck joints is to lower the string height at the saddle. Eventually, as the body continues to deform, one runs out of sufficient saddle height to lower it any further, at which point the most common correction is to reset the neck. That is, when the neck relief is correctly set, the strings are too high at the 12th fret and there is insufficient saddle height left to reduce it, and the bridge is not overly thick, the angle the neck makes with the body needs to be altered.

For guitars with a Martin-style design target (1/2" string height at the bridge), a quick test is the "straight-edge test". Note that this is not accurate for guitars with a different design target.

For many instruments, the time to a neck reset is in the range of 10 to 30 years, while some instruments never need one. It depends, in part, on how heavily the instrument is built. There is no accurate way to tell in advance how long it will be before a particular instrument requires a neck reset.


On guitars with an adjustable truss rod installed, the amount of relief in the neck can be adjusted by tightening or loosening the truss rod nut. The adjustable truss rod has only one function, and it is to adjust the amount of bow in the neck. Generally, adjustment of the truss rod should not be used to alter the height of the strings. Adjustment of the truss rod has no effect at all on the neck angle.

Loosening the string every night will wear out strings very quickly. In no time at all you will have ruined enough strings to pay for an eventual neck reset. It isn't a recommended practice.


If you apply the reasoning above the straight edge test isn't necessary. If you have a desirable string height at the 12th fret, the neck has the desired amount of relief and you have sufficient saddle protruding from the bridge, you don't need a neck reset.


If you are buying a quality instrument that is worth spending $350 to $500 to eventually have it repaired, a neck reset is just part of the cost of ownership. If it is an inexpensive instrument that is not worth putting that much money into repairing, you are best to avoid purchasing that instrument.

Last edited by charles Tauber; 04-11-2018 at 04:13 PM.
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Old 04-11-2018, 06:22 PM
calstang66 calstang66 is offline
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Thank you for the information in the above posts. After reading them, it would seem that the first thing to look at when buying a used guitar, would be the height of, the amount of saddle, which should be min 1/16" and ideally 3/16".
Now I'm going to guess about the difference between "bow in the neck" and "neck angle"'
  • Bow is the bowing of the portion of the neck, starting from the body/neck joint up to the tip of the headstock, variable by adjustment of the truss rod.
  • Neck angle distortion is when over time, the tension in the strings causes the instrument to fold upward at both ends, like "into the sound hole", the guitar folds up, sound hole being the crease. The middle of the guitar (at the sound hole) kind of sinks, the string pull up on the bridge causing that end to move upward, the strings pull up on the neck, causing that end to move upward. Like you have a book open to the middle page, laying very flat open on a table, then you lift up both front and back covers a bit, so the book is partially closed, the 2 ends are up in the air, the middle still on the table, it looks like the letter V.
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Last edited by calstang66; 04-11-2018 at 06:46 PM.
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Old 04-11-2018, 07:21 PM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by calstang66 View Post
Thank you for the information in the above posts. After reading them, it would seem that the first thing to look at when buying a used guitar, would be the height of, the amount of saddle, which should be min 1/16" and ideally 3/16".
I should have worded that better. The maximum, ideally, should not exceed about 3/16". It is not ideal to have 3/16", necessarily.

The first thing to look at is "the action". The action is primarily a result of the amount of bow/relief in the neck, the string height at the nut, the string height at the saddle. In other words, does the instrument play buzz-free with the amount of ease you want? If not, what latitude is there for adjustment to get it to play as you want? Is there enough saddle height protruding from the top of the bridge? Does the neck have the desired amount of relief?

If it does play the way that you want, how was that achieved? Is the saddle protrusion too little or is it within desirable limits? Does the bridge look like it was thinned?


Quote:
Now I'm going to guess about the difference between "bow in the neck" and "neck angle"'
Pretty much, though the truss rod effectively only changes the neck curvature between about the nut and about the 9th fret.
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Old 04-11-2018, 07:52 PM
D. Churchland D. Churchland is offline
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I want to know what luthier charges 350$ for a neck reset. Most pros that I know personally charge in the neighborhood of 500$. And that varies greatly depending on the make/model/year/condition.
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Old 04-11-2018, 08:22 PM
mirwa mirwa is offline
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350 is my standard charge on a neck reset and that is in aussie dollars as well

Steve
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Old 04-11-2018, 10:43 PM
calstang66 calstang66 is offline
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Quote:
Originally Posted by Will Kirk View Post
I want to know what luthier charges 350$ for a neck reset. Most pros that I know personally charge in the neighborhood of 500$. And that varies greatly depending on the make/model/year/condition.

Certified Martin Repair Luthier, John Cushing, Jefferson City, TN 423-475-9444
most of his work is Martin guitars shipped to him.
Old fashion guitar builder, repairman.
He does stuff while I wait, set up, scratch removal, new saddle, truss rod...
Uses special wet 2200 sand paper soaking in soapy water to remove scratches.
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Old 04-22-2018, 09:04 PM
D. Churchland D. Churchland is offline
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Price varies alot by area then. Where I lived before I moved the going rate was 350, like I said before my current area the rate is 500$ and up. Really was just curious, cool info to have.

Last edited by D. Churchland; 04-22-2018 at 09:06 PM. Reason: splelling
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Old 04-22-2018, 09:58 PM
mirwa mirwa is offline
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Quote:
Originally Posted by Will Kirk View Post
Price varies alot by area then. Where I lived before I moved the going rate was 350, like I said before my current area the rate is 500$ and up. Really was just curious, cool info to have.
Locality, skill set, cost of living, overheads, access of materials all these contribute to a final cost.

Most times I do a neck reset its also done in conjunction with other jobs, example fret level and setup, or new nut and saddle, so it can round up to 500 quickly

Steve
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