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I am building a classical guitar and am debating what neck joint to use.
When I started this madness thirty years ago I built steel string guitars using the traditional classical "slipper -foot" joint, so I am quite familliar with that style of construction.I definately don't want to do that again because I can't see any advantage and do see a lot of disadvantages on the construction end.
The recent Jazz Classicals I have built I have used a simple glued tennon.
This guitar is going to be a relatively "traditional" looking style classical.
I am thinking bolt-on of some sort.
Any clasical builders out there have any opinions on this?
Thanks, Brad

Hi Brad,

Yeah, I build classicals. I use the traditional Spanish heel/foot construction, and have used it on all my builds, save one. On the one exception, I managed to screw up the side slots so badly, I cut the neck free from the heel block and bolted it on after I'd cooled down. I used just a simple butt joint.

Now I don't necessarily advocate this same approach. But I will suggest that using a simple mortise-and-tenon joint with a couple of bolts and their threaded inserts will result in a very tight neck-to-body joint.

I have two classical builds coming up -- both 10-strings -- and I plan to use a bolt on neck with each one. Why? Because it is so much easier to contour the neck, mostly, which for a 10-string classical is a bear and a half.

The mortise and tenon method of bolting on necks is becoming an increasingly popular method for joining neck to body with steel string guitars. Why should they have all the fun?

Best,

Michael

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Hi Brad,

I have also used only spanish heel/foot construction in my classicals. The video from Robbie O'Brien pretty much shows you a full-proof way of making the joint, even on your very first try. I know that is my standard way from now on.

From a player standpoint, I shopped and bought many guitars before I ever started building, and I must say I never looked at how the neck was joined. If it sounded good, that's all I cared about. Honestly, I didn't even know to look at the neck joint. One thing I did consider was how heavy the guitar was. I tended to shy away from heavier guitars. I don't know if the hardware in other neck joints would add any real weight, but that's the only thing I might have noticed if it did.

Cheers!

John

Michael and John,thanks for the input.
Having used both methods of construction, I found that it is much easier and efficient to have the body "free" of the neck,especially when routing and installing the binding,sanding etc.
John, I agree that most players don't care what type of joint is used as long as the instrument sounds and plays good.
I don't think 1 or 2 bolts will add detrimentally to the weight.
Thanks, Brad

I use a single tapered tenon for all of my necks, classical, steel string and archtop. It tapers toward the back like a dovetail, but the sides are parallel when you look at it from the top. It comes apart like a dovetail, but is easier to fit. I feel it's alittle stronger because there's no end grain gluing, but that's just my opinion.

It certainly is easier to fit and finish things with the neck and body seperate!

Alan,

How do you cut your tapered dovetail? Do you use a jig of some sort, or?

I have built one steel string so far, and I used a mortise and tenon joint with it -- drilled for a bolt-on fitup. I have a milling machine, so I used the mill to cut the joints after I'd rough cut them with hand saws. (My table saw basically sucks, and I wouldn't even think of using it for lutherie, so I must adapt.) I plan to use this same setup for my upcoming 10-string classical builds.

I reckon I can find tapered end mills to cut dovetails, but considering that a mortise and tenon neck joint is not really intended for the use of glue in the fit-up, I'm wondering if the concern about endgrain gluing is a valid one? Cuz the only areas where I applied glue during the fitup of my SS's neck was at the fingerboard extension over the soundboard and the heel cap.

Just wonderin'

Best,

Michael

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I build almost exclusively classicals and I always build with a spanish heel/foot as that what I learned and have stuck with it. Eugene Clark who builds great flamenco's has repaired alot of historic classical guitars and swears that he has never seem a spanish contruction guitar that needed a neck reset. Most classical swear by spanish contruction as religiously as some steel string builders do about dovetails (neither need much repair but when they do are tough to get apart).

Having said that two of the greatest classical builders alive do not do a spanish heel slot type construction.

Jose Romanillos uses the tapered wedge on each side of the heel block (on the interior of the heel) as it secures it well but is also easier to repair later on. I would call this a modified spanish construction.

Thomas Humphrey builds with a bolt on neck that is based on Cumpiano's construction and doesnt feel that it has affected the perception or quality of his workmanship.

If you have a good setup and are comfortable with a bolton neck then I would stick with that...especially since you are going for a jazz classical market, not the very conservative pure spanish classical market.

Michael:
Again, the joint I use is not a dovetail. From the top it looks like a straight mortice, but it's narrower at the bottom than the top, so it's a 'single tapered mortice'.

I used a glued straight mortice for a while, until somebody pointed out that if you steamed the glue to get the neck off you'd also cause the tenon to swell, locking the joint. So I went to a glued, single-taper mortice.

I cut the pocket with a router and a simple jig. The tenon is easy to rough out with a saw, and then it's time to sharpen up the chisle.

I've seen all too many Spansih construction guitars that needed _something_, as the necks pulled up and the saddles got cut away to nothing. Even if the neck doesn't bend the body often does, allowing the nut to go up as the top dishes. Maybe Gene sees a better class of classicals than I have tended to.....

Usually you can pull frets on a classical and plane the fingerboard thinner at the nut end. Bent necks are often straightened with heat, although I've never had that work out as a permanent repair when I've done it. In other words, you can often get away with avoiding a reset on classicals, but that doesn't mean the necks never pull up. I will admit they do so less than steel strings, but classical necks are wider, often deeper, and carry less tension. The few classicals I've seen that had steel strings put on (other than Thomastic "S" series), and on which the bridges survived for any length of time, sure needed resets. Couldn't do them, though.

The point is not that one way is 'better', but rather that each way can work in its proper context. With steel strings you probably need to make the neck removable (I used the slotted neck on steels for a long time, and most of them are still OK, but...), whereas on classicals you probably don't. Classicals give you more choices.

One reason I use the plug-in neck on my classicals is that I don't build them on a workboard in the Spanish way. The work board sets the neck angle at the start and holds it all through the closure of the box. Without it it's hard to keep things lined up properly with a slotted heel, so....

Exercizing my "traditionalist" standpoint... I'd say that when you're in doubt just do it the traditional way. I use the Romanillos joint which is a good one, but a simple slot works perfectly for most makers.

If Torres and Santos Hernandez connected their necks with a simple slot, then that should be a great place to start. Guitars are mysterious things, and if you want to have the kind of results the old Spanish masters had the best place to start is with their techniques and designs - if it ain't broke and all of that.

I don't see any sense in doing what is "easier", and I don't think its beneficial to approach a classical in the same way you'd approach a steel string (ie. seperate neck and body, just because it makes the binding easier). On the same token, if I were making a steel string I'd do a dovetail.

If you use Spanish style construction and you're worried about a future neck reset, just make sure you glue your fingerboard with hide glue so it can be replaced in 30 years if needed. Many old Spanish guitars have had their fingerboards replaced, and its no big deal.

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Not to argue the point that most great classicals were and are made with the Spanish style joint-there are exceptions-Fleta used a dovetail joint.

Sure, Fleta made many diversions from tradition, and still produced guitars many people adore. It can be done, its just a different approach with different results. But it doesn't seem to be one that is very often emulated or requested.

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jfrench wrote:
"Guitars are mysterious things, and if you want to have the kind of results the old Spanish masters had the best place to start is with their techniques and designs -"

I think that's a bit of a red herring, although there is also some truth behind it. Confused? ;)

Torres lived in far different circumstances from ours. On the one hand he had a long tradition of guild regulation which, even if it was not iron clad by his day, still strongly shaped 'standard prcatice'. Just because somebody did something a certain way in 1492, and it got enshrined in the guild regs, doesn't mean it's wonderful.

The traditional Spanish method of building makes perfect sense if you keep in mind that wood was expensive, and labor was cheap. Romanillos mentions several times in his book the lengths that Torres went to, to get good top wood, and back and side stock was much harder to come by. The traditional methods really conserve on wood, at the expense of some time input: it takes longer to laminate a heel and cut a V-join than to bandsaw a neck out of solid stock, for instance.

The traditional method was also a great hand-tool method of mass production within the constraints of the time. With several workboards you could work on a number of instruments at a time, shifting from one to the next to allow time for the hide glue to set up. The tooling needed was minimal, and you could get by with a small bench for the most part. In short, they did it that way because it made sense.

The plug-in neck really is a router technique for a small shop builder, and thus by definition a late 20th century method. I've cut those joints by hand: it's no fun, and the traditional joint is far easier in that respect. The trick is that the traditional method more or less requires you to use tentellones to join the top and sides, and that's time consuming by modern standards. These days time is much more 'expensive', and materials, at least in the USA, are practically free by comparison.

I would agree with you far more readily if it could be shown that there is _any_ acoustic difference between a properly constructed plug-in and a Spanish joint. Sometimes people talk about 'damping' of the glue line, but I've never seen any measurement that backs that contention up. Remember, violins have used plug in necks for a couple of hundred years, and before that they just butted them on and threw in a nail or two. All of Strad's instruments left the shop that way, and nobody complains about the loss of tone in his neck joint! ;)

There's also the issue of changing standards. Back when I started making guitars workmanship and finish standards on 'average' instruments were much lower than they are now (the great ones were always great). A little waviness in the sides and 'dry' polish around the neck joint were not considered sins. The older guitars that I've worked on often show a level of detail that would be hard to sell now, and most Spanish guitars left the shop thirty years ago with a very thin French polish by our standards. It was assumed you'd be bringing it back for touch-ups over time. These days any handmade guitar really has to look like a new Lexus to have a prayer in the markeplace. It's a lot easier to get the finish 'perfect' if you don't have to work around the neck and bridge, so building the neck and body seperately makes sense in today's market.   

Finally, I'll say that in general I _do_ agree with you: the old ways _are_ often the best. I'm certainly willing to admit that there may be reasons for doing it that way that we don't know about yet. But at the moment I don't know of any rational reason not to use some sort of plug-in neck on a classical, and have seen and heard no difference between guitars made in the old and new ways that I could confidently attribute to the neck joint. If it's good enough for Richard Brune, it's good enough for me.

Yeah....What Alan said!!

Al - well stated.

At the moment I'm doing exactly what you mentioned.... gluing the sides to a soundboard with a couple hundred tentallones. Time consuming? Sure, but that depends on how you look at it. I went to the store, grabbed a six pack of Modelo Especial, flipped on one of the benedetto DVDs and had at it. The lower bout took about an hour, and I've still got 4 modelos left. Personally, I enjoy this part.

But your point is well taken. There is nothing to say a neck joined to the body in the traditional way is better for the sound than a dovetail or tenon. The difference for me is not having to invoke the name of Fleta when a customer asks what kind of neck joint I used, or have to justify my methods to a conservative guitarist.

Certainly, your method must be faster, and I doubt there are any drawbacks to it. But I prefer to err on the side of tradition here.

Though I'm up to my neck in things to do, I take my time and I really enjoy the traditional way of doing things. To me its an important part of what I do. I really enjoy the more time consuming aspects of guitar making (rosettes, v-joints, tornavozes). It adds time to each guitar, but for me its rewarding in the same way that I would imagine your scientific research into guitar acoustics is for you. Your work must take a considerable amount of time and energy beyond simply making a guitar...

One day, if you're up for it, I'm going to ship you one of my tornavoz guitars for you to look at with a scientific eye. I think it'd be fun for the both of us.

Best wishes,
Joshua

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One point though - it is certainly possible that the neck joint has a bearing on sound. And that possibility is enough to keep me doing it the way the makers I most admire do it.jfrench38575.690150463

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jfrench wrote:
"One day, if you're up for it, I'm going to ship you one of my tornavoz guitars for you to look at with a scientific eye. I think it'd be fun for the both of us."

That would be fun.

When I read Romanillos' book I got curious about the tournavoz, and did a little experiment on my 'corker' guitar, which exists for that purpose. I made up a tube of cardboard as close as I could make it to the pattern in the book as I remembered it (I'd given the book back to its owner) and stuck it in the soundhole. The change in te tone was immediate, and not at all to my liking. Basically it killed the 'main air' resonance that gives the 'body' to the lowest notes. It souded a lot like a Renaissence guitar: all high end with no fundamental on the low strings, but it was louder than the small, early instruments, I think.

Now, there are a host of objections that can be raised to this, and that's one reason I haven't talked much about it. For one thing, cardboard and copper are somewhat different materials. Also, my tube was straight rather than tapered, and I was not at all sure about whether to put holes in the lower edge or not. I keep thinking I'll get a better pattern and make one out of some aluminum flashing, but time, time, time.... Maybe if you just sent along the pattern, or one of the units itself with some tips on installation?

I, too, enjoy some of the time consuming parts. Making V-joints, rosettes, and so on, is a lot of fun. I'm not sre the plug-in neck saves all that much time, and in a small shop it's not nearly the issue it is in a factory. In the end, you do things the way you like to, and justify them however you can.

_Nothing_ takes longer than science, except maybe art. We do it because we can't imagine not doing it.

Al - Thats exactly the effect I would expect (in most instances) from adding a tornavoz to a guitar. Torres was able to achieve the opposite effect. Interesting stuff.

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Well, if Torres got a different effect then we'd better look into it! I'll have to get the specs and try that out some time on the 'corker'. I't so nice having a dacent sounding guitar that I can cut up when I want to!