BYO - Selmer Modele Jazz - Does it have a Truss Rod?

bluemoves

Did the originals have truss rods?

Do the modern replicas have them?

Doesn't it make the neck weigh too much?

Have most of the originals had to have their necks 're-set'?

I heard something about aluminium strips..? Non-adjustable.. (is that the way to go?)

TL;DR - HELP!! :D

Bones

I like truss rods. No clue about the originals.

ChrisMartin

Many refer to truss rods as in the modern adjustable type, but some old guitars had fixed rods of varying materials added for stiffness. It is not hard to add either a straight rod or two, or an adjustable one if desired. Using aluminum in the past, or more often these days, carbon fiber, certainly will not add any noticeable weight. In many cases it may not be obvious if there is a rod of another material inside a guitar neck unless it can be X-rayed. On the other hand many old school luthiers knew how to work wood correctly, and depending on the timber used and especially the grain could make a neck that has lasted down the years without any need for additional stiffening.. Then there is the laminate type as used by Favino where a sandwich of timbers with opposing grain patterns would be far more stiff and stable than a one-piece neck, (usually Favinos had five pieces of maple/rosewood/maple/rosewood/maple).

I have an old Di Mauro that had three thin aluminum strips added some time in the past but I have also routed and glued carbon fiber rods in others. Normally if the neck is otherwise good and it is all clamped straight while the glue is setting it will stay straight. As these are not adjustable you can add some neck relief by shimming between the fingerboard and a straight edge but whatever you do at that stage will be permanent. If you do not want to risk that, then yes, adjustable is the way to go.

But bear in mind all of the great players and old records you are hearing from Django, Matelot, Baro or Oscar were using guitars made a long time ago without any hi-tech trickery; just wood and skill.

The question of resetting necks has nothing to do with all of the above. Old guitars were made using old glues - hide glue, or various animal and fish concoctions (yes, really, Google the history of glues for a laugh). These lose strength and soften with time particularly when exposed to heat or moisture and over time the tension of the strings will cause the neck to move in relation to the body. No truss rod can cure that, it will have to be removed, cleaned and reglued at the correct angle.

Finally, as you have enquired elsewhere about making your own guitar you will need to consider the question of glues. The traditional hide glues are still used, and even recommended by many as they allow for easy separation and reassembly should any repairs become necessary, (Titebond hide glue is widely recommended) something not so easy to do with more modern (but stronger) glues.

ChrisMartin

The only way I know there are three thin aluminum rods in the neck of this Di Mauro is because the ends are visible extending a short way above the nut.

crookedpinky

I've got an Anastasio which has a very slim maple neck with a square steel bar inserted from the nut to the body join.it's still as straight as it's been since it was completed on 24th December 1986.

klaatu

Many years ago I bought a Bob Holo guitar and asked Bob why there was no truss rod. He responded as follow (and I don't think he would object to it being cited here):

The neck has dual carbon reinforcement - and it's good carbon too. It's military grade unidirectional fiber epoxy potted pultruded carbon and is textured before it is glued-in to further improve its mating to the channels in the neck. So - it's very stiff. 

Truss rods are funny things - I don't know if I'll ever use them. They don't actually do what people think they do. They are a support, but they really only determine the curvature of the neck between about the 3rd and 9th frets - they don't have anything to do with neck angle or stability as people often think. Because they're not attached along their full length, they sort of act like a really strong cable tied to the 1st fret and the 14th fret. If you tighten one, you can pull a neck into a bow - or if you loosen one that is bowing a neck you can get it to stop bowing the neck. I guess that push-pull rods can do that same thing in reverse too - but truss rods can't help with the two things necks most need... stability over the body join & help withstanding torsional pressures that come about because the tension of low strings is generally greater than tension of high strings. 

Truss rods are really handy for factory guitars because the throughput is so high that occasionally you'll get neck lumber that is a little on the green side and you can't just stop production - so as it dries and shrinks relative to the ebony/rosewood fretboard it'll pull the neck into a backbow and the truss rod can fight that. (same thing happens over the body join) but the problem with fighting tension in a neck is that tension tends to find a way to express itself over the long term and that's why you see some trussrod necks piping under torsion and/or developing humps over the neck join to the body. Small shops generally have the advantage of having a low enough output to where we can make necks up ahead of time and just let them sit till they get dusty and dry because we don't have to ship a hundred guitars every Friday ... (thank god!) and so proper wood stability is less of an issue - and the carbon can then be used as purely a stability reinforcement to keep an otherwise tension-free neck in its proper position.

Now - that being said - all guitars made of wood will move with temp & humidity changes, so your neck relief will change with the seasons -so will the amount of arch in the soundboard and the combination of these two will lead to changing action season to season - but as long as it's gradual - it should be fine - just add and subtract shims to keep the action as you want it.

Bones

Yes, what Bob said. Truss rods (adjustable type) are for adjustment not necessarily stiffness. I kinda like that because if (when) the wood moves over the years it's easy to get the action and more importantly relief dialed back in.

I've used carbon fiber rods (rectangular) for stiffness too. Not sure if they were necessary. I've also not used them. Have not had problem either way. Whether you add carbon for stiffness you really need to have a good stiff piece of wood for the neck anyway so....