To Truss rod or not to truss rod...that is the question...

[invguy921]

We're all seeing different approaches to design in guitars and frankly just about everything else on the planet as well. Old ideas being thrown out in exchange for new and better ones. Some time ago, I personally "bought into" the notion of the design that McPherson uses which is carbon fiber in the guitar neck and no truss rod. I can only guess that part of the reason for this with McPherson comes back to Matt McPherson's pride in his design and not wanting anyone to adjust the guitar and possibly mess it up. Presumably McPhersons need very little adjustment and hence the only way you can get and Mac adjusted is to send it back to them...a costly and time consuming option. Not to mention, McPherson guitars may "die" with Matt someday leaving McPherson guitar owners with limited options for the future owners.

I've always liked, and I think we all like the idea of a guitar that needs less adjustment. And yet it is wood and certainly wood moves with climate change, as well as just through ageing of the instrument. I know that some builders don't like the idea of local luthiers and owners tweaking their guitar using the truss rod. We've all heard horror stories of goofballs tweaking their guitars to the detriment of the entire instrument.

Realizing/assuming that 99% of the builders (production and custom) out there put truss rods in their guitars, I can guess there must be reasons why the majority haven't changed directions and followed McPherson's "no truss rod" strategy. Tell me please...why not just quit putting truss rods in guitars and start adding carbon fiber and make the neck super stiff?

Let's have a rousing discussion on this. I would love to get some commentary from all sorts of people, particularly builders on this topic. Thx!!

[redir]

Do a bit of research on the engineering of beams and the neutral axis and further that with the discussion on CF rods. Basically they do just about nothing unless they are buried very deep into the neck or inlayed up under the fretboard, and even then...

I have built a few guitars that have no truss rod and they are fine, until they are not. They were built in the tradition and for extra light strings, is the only reason why. I never really understood what the big deal is in regards to disaster stories. I've seen people do stupid things with truss rods but never break a neck or something like that. And for the rare occasion someone does something stupid it's not enough imho to warrant eliminating truss rods in their entirety.

IMHO 99% of the guitars out there will benefit from having a truss rod. Sure a guitar can be built without one and function just fine and even be able to be repaired in the future but the truss rod just makes it so much better. I like to kind of think of it like the difference between a dovetail and a bolt on neck joint. The dovetail is great, till it isn't, and then you need a full neck reset. With the bolt on you reset the neck in 15 minutes.

Luthiers through time have solved a bunch of common problems with guitars, the truss rod is one of them and it's been around a long time. I see no real reason to go back.

[Captain Jim]

OR... you could just go "all in" and get a carbon fiber guitar. McPherson offers two models (no truss rod). I have three carbon fiber guitars (two Emeralds and a RainSong) - they each have a truss rod, but have not required an adjustment. Not the case with my wood guitars.

I am enjoying the tone, comfort (CF guitars can be made more ergonomic), and ease with carbon fiber. I don't see any new wood guitars in my future.

[LouieAtienza]

Wel the CF is pretty expensive compared to truss rod, the install more time consuming, CF dulls carbide tooling (unless you have expensive PCD tooling), and you need a way to mitigate CF dust.

McPherson supplies 3 saddles, of different heights, for adjustment of action. The neck is bolt on, with Belleville washers to accommodate for wood movement. And the bolts are received by a huge tapered brass cylinder set into the heel, triangulated with a stainless steel screw. The fretboard is also cantilevered over the body. So there is a design philosophy to it... but if you want a certain "relief" on the neck, that would be difficult to adjust yourself..

Non-adjustable necks can be the right choice for a number of reasons, but may not be the right choice for everyone. I won't debate the tonal benefits, but I do believe there are tonal differences between adjustable and non-adjustable necks. Since I own several vintage Martins, I have several non-adjustable necks and they give me zero trouble. When Howard Klepper built me a guitar, we chose a non-adjustable neck design. No regrets.

[ChuckS]

Originally Posted by redir

...[snip]...I have built a few guitars that have no truss rod and they are fine, until they are not. ...[snip]....

One thing I like about my acoustic guitar 'hobby' is that there tends to be minimal repair work necessary, hopefully not for decades in a well built instrument. I really dislike when things intended for pleasure become a burden. Sure, there's maintenance like replacing strings and occasional fret work or setup work. With an adjustable truss rod, any needed adjustment to neck relief falls into the maintenance category; no big deal. Without an adjustable truss rod, any needed adjustment falls into the repair category, and I might tend to put up with less than optimal playability for quite a while before I get it taken care of. My last two commissions use very durable fret material (either stainless steel or gold EVO). These fret materials provide two things for me: less frequent down time for maintenance; more time where playability is not compromised by fret wear.

A while back I was considering getting a used Martin OM-18 Authentic. There were a couple things that made me drop it from consideration, one was lack of an adjustable truss rod. I'll accept that there may be some tonal contributions from designs with non-adjustable necks; I guess I need to find my desired tone from alternate design approaches.

I'm glad there are lots of options, so those of us who have a strong preference (either way) can get what they want.

[justonwo]

The only downside to an adjustable truss rod is weight and the potential for a neck-heavy guitar. They certainly come in handy when you really want to put a fine point on relief. That said, if you want an ultra light guitar, carbon rods can make the neck so stiff the relief will never change. If you know what relief you want, then there isn’t much reason to change over time.

I don’t think luthiers using a adjustable-less truss rods fear someone adjusting the setup. Virtually all builders I’ve worked with recognize setup is personal and that the player will want to tweak it. I think it’s about weight savings, balance, and staying true to some of the older designs.

[LouieAtienza]

Well the CF rods in mcPherson, PRS, and the like, as well as the t-bar and square tube in Martin, are trussrods, just non -adjustable.

[Borderdon]

FWIW, my 45 yr. old 000-18 has non- adjustable neck reinforcement, and is as good as it ever was with excellent relief after all these years. Not better, not worse than, just saying' --

[Bruce Sexauer]

In this time of diminishing material quality, truss rods allow continuing adjustment to compensate for unstable materials. They are also useful when one decides mediums are preferable to lights.

On the other hand, when a builder uses properly milled and dried Honduran mahogany predictions re structural stabilty under tension is variable humidity can be pretty much counted on. And, when a guitar is built to use a specific string tension, and NOT any other, then a guitar can be set up with a fixed tension carbon fiber truss system and be expected to last a lifetime.

A non-adjustable system is not “one size fits all” and is merely an option on my guitars, but for the right person it is an elegant and reliable alternative. I charge a little more for it not because of a parts and labor increase, but because the relief is not perfect right out of the chute about 1/3 of the time, and since there is no adjustment, I have to resurface and refret.

As opposed to my standard adjustable steel system, carbon fiber saves about 2 1/2 ounces in the neck. I have not been able to discern ant tonal difference attributable to the difference, and personally believe that a rigid neck is the ideal, and either system will produce it. The lighter neck does feel good to me, though.

[mercy]

This conversation seems to have a lot of theorizing and a couple of owners who say it is no problem. If this is correct I say lets listen to those with the actual experience of owning one over a period of time.
And if there is tone loss with a adjusting rod it seems to me we need to look at the assumption of the necessity for a rod again.
I wonder if the adjusting rod is just a convenience for the builder.

[fitness1]

I'd like to add another angle to the discussion, because I don't have any experience with a truss-less instrument.

What about a laminated 5 piece neck out of the right woods (like my Charis) The stiffness factor has to go up, I'm assuming, and the need for a truss lessened?

Just asking.....

[LouieAtienza]

Originally Posted by mercy

This conversation seems to have a lot of theorizing and a couple of owners who say it is no problem. If this is correct I say lets listen to those with the actual experience of owning one over a period of time.
And if there is tone loss with a adjusting rod it seems to me we need to look at the assumption of the necessity for a rod again.
I wonder if the adjusting rod is just a convenience for the builder.

It's a convenience for the owner as well. If I, say, built a guitar with a non-adjustable trussrod for someone and they told me they play 13-56 strings, then 2 years down the road they decide they need to play 11-52 strings, the neck may not have the same relief, or the top may be too stiff, or both.

As to tone loss, the tens of thousands and more of great sounding guitars out there now with adjustable trussrods tells me that there is really no discernable tone loss if any. You just get a different tone with a non-adjustable trussrod, and it's just a matter of preference.

As to weight, there are some builders that would argue that they feel a neck with more mass is "better". Matt McPherson for one. Then there are some that argue that a lighter neck makes a guitar with better acoustic properties, like Bob Benedetto. They're probably both right, based on what they hear and like, personally - McPherson talks a lot about sustain, while Benedetto is of a jazz background.

[Silly Moustache]

I had lots of experience with guitars that had no adjustable truss rod - Martin were very slow to get on board ....(of underboard).
Factior 1 - not all people like the same amount of relief as others.

Factor 2. Guitars and necks are made of wood, which moves , but also steel bends.

Factor 3. Why not do as Collings do - adj,.truss rod AND carbon fibre rods.

[Rodger Knox]

Originally Posted by fitness1

I'd like to add another angle to the discussion, because I don't have any experience with a truss-less instrument.

What about a laminated 5 piece neck out of the right woods (like my Charis) The stiffness factor has to go up, I'm assuming, and the need for a truss lessened?

Just asking.....

Maybe, maybe not. My first has a laminated maple neck, and it was too stiff for the strings to pull any relief, so the double action rod was necessary to add some relief. It's easy to build a laminated neck that's stiff enough to resist string tension, it's a little more difficult to build the perfect relief into the fretboard.