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I finally coughed up the money for Ervin Somogyi's books, and have been churning through them at a rapid pace over the weekend. Fascinating stuff, and very helpful. Plus I've already been saved the trouble of several experiments I'd thought of trying sometime

One thing that particularly caught my attention is his headblock design, and the fact that the neck is permanently joined upon attachment.

Neck joinery has been one of my big fears of whether I'll get it right or not. I decided on a mortise & tenon bolt-on for my first one, but I'm thinking about trying a classical-style integral headblock next time. It just seems more logical to me to build the box with the neck attached rather than going to the trouble of making a good joint, if the success of that joint means that it should never have to be disassembled anyway.

Has anyone here attempted such a thing, or have any thoughts on the matter? My main worries would be
a) bridge area bubbling up over time, thus needing to adjust the neck angle eventually
b) neck deforming over time
c) getting the angle wrong to begin with
d) I've never seen it done before, so I must be missing something

The first one seems the most troublesome. With the integral neck extending all the way to the upper transverse brace, that portion should be plenty sturdy. But the lower face seems weaker and more prone to warping.

Neck warping should be countered by the truss rod, especially being able to have it extend all the way to the UTB. But I suppose I should also include carbon fiber reinforcements to be sure, as well as to counter twisting and sideways warp. I just don't want little splinters of that stuff getting everywhere...

So, am I missing something, or do most people just prefer the challenges of separate neck construction over those of an integral neck?

Dennis: It's not so much the top coming up over time or the neck bending. It's the slight deformation of the total box over time. As you know the neck set is a very fine accurate adjustment and it does not take much rotation of the neck block,or neck,neck block combination as in the classical form to cause a change of the neck angle. For me I would rather have an adjustable neck joint,be it a dovetail or some kind of mortise tenon. This hopefully will turn into a very interesting thread. I do think that the integral joint is stronger but am not convinced it will never need adjusting. If it does,slipping the back is about the only way short of taking the box totally apart. Interesting question Dennis.
Tom

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Dennis,

What your not taking into account is the substantial force the 6 steel strings exert on the system. Over time the bridge will start to rotate, the neck block will start to slip and the action will become too high to be brought back in line with anything short of a neck reset. The seperate neck and block were not developed by accident. When the neck is integral with the neck block you have a situation that is more difficult to deal with when the inevitable occurs.
I like the idea of a Spanish heel as it gives far more gluing area to counteract the forces involved. Do a search on neck construction authored by forum member ColinS. This is the style of construction that I have adopted and believe to be a great improvement over the current standard practices.

Steve

I'm surprised that anyone would advocate that style of neck joint in a SS guitar. I remember the very first book I had on guitar building by David Young suggested that one create a butt joint and epoxy the neck right on! I wonder what the condition of those guitars are today. If the argument is that you get better tone from a Spanish joint over bolt on or even dovetail I don't buy it. Also another point, I don't think the Spanish method is any easier than a bolt on, in fact it's quite the opposite imo. For nylon string guitars it ok. I have a 40 year old classical guitar with plenty of saddle height to adjust the action but of course I've seen many quality Spanish guitars come through my shop that were grounded out as well. So even on low tension nylon guitars you have to be careful and make sure there is plenty of room for adjustment down the road. When I build with that method I do two things, I push the height limit on the neck angle/saddle height and I tend to use a thicker fingerboard. That way in the future if saddle adjustment alone cannot solve the problem then a refret and resurface of the fingerboard just might.

On the other hand, given the history of the steel string guitar couldn't you just as easily say:
- Necks that are easily disassembled will always need resets
- The standard practice of a neck which can be easily separated from the body was developed by a handful of manufacturers for whom a major concern may have been division of labor on the factory floor?

I understand the advantages of an easily repairable/separate-able joint, but it doesn't seem unreasonable to consider whether or not that actually causes the joint to need need to be repaired sooner than later. I'm not so sure that Martin and other earlier manufacturers were planning early on that the guitars they were making in the 20's would require neck resets a few decades later. They were mass producing instruments and it makes sense to be able to have one guy working on the neck while another is working on the body at the same time.

There are at least a few makers (Somogyi, George Lowden) that feel that making a more solid/permanent joint and a very stiff upper bout/neck block design is going to greatly reduce the need of a neck reset. I'm no expert by a long shot, but the argument that neck joints have always been made to be repairable and these neck joints will always eventually need to be reset doesn't really make a great case for neck joints that are easy to take apart. Those guys might be wrong, we don't have a century of history with their instruments. I just don't think these ideas can be so easily dismissed.

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Jonathan's (eat paste? blah) post says pretty much my mind on the subject, and I applaud your open-minded approach Todd, with the warning of knowing all the factors. How long does it take to understand all the factors? A lifetime, I think.

The tiny guitar shop should not be limited to factory methods to achieve a better guitar.

The problem always comes when you want to build more and more guitars, and need to sell some to finance your habit. That means a potential customer is going to critically question every method you use, comparing it to long-standing factory practice. How are you going to become well known for distinctive, innovative guitars, if the buyer is locked in a traditional mind-set?

I guess you have to make sure your finish is real shiny.

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I built steel strings with integral necks for a long time, and have had few problems I can recall that were due to that feature. However, I switched over to plug-in necks because, as 'standard practice', they're easier to sell. People feel better knowing that a re-set is easy, even though I do suspct it's one of the things that leads to a fair number of re-sets being needed. I also think that some form of A-brace, coming up the sides of the soundhole, through the UTB, and inletted into the neck block, goes a long way toward stablizing things. But there is no denying that there's always a chance of the action going south on you, and the removable neck is a good piece of insurance.

Alan, did you, or do you know who 'invented' the upper A brace? I think I picked it up from you, and have used it since about 2000.

I build guitars with a traditional look, but I do have my distinctives. Just this weekend I found myself explaining in detail the upper A brace to a potential customer who questioned its use in a vintage style guitar. There is a rumor that the popsicle is the superior method of resisting neck block rotation.

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I think that there are two concepts being put together here which are not necessarily related.
- the adequacy of the joint
- the adequacy of the structure of the box

Unless a dovetail joint is poorly made and just put together with lots of glue, it is not going to move and cause the need for a reset. Movement of the dovetail joint will be readily seen as a gap between neck heel and body.
It is deformation of the box which is the culprit, not which joinery technique you use for the joint between neck and block.

I have just done a repair of a 10 year old flamenco guitar with a Spanish heel joint and high action with no break angle at the bridge. Had to go with a new thicker tapered fretboard.
I build my steel strings with bolt on adjustable necks.

Hi Jeff,
Not meaning YOUR guitars, but...
Is the bolt-on-neck just a happy way to connect the parts, or is it used out of fear of the box deforming?

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I have built close to 20 guitars with that style neck joint and have yet to have a problem. It does make it a little tougher to get that neck angle right. I tend to get the final angle when i build my bridge and thickness it accordingly. A reset is possible by lifting the back from the heel then re gluing(a ich but possible) I make my neck blocks with a spainish foot top and bottom. I like that extra mass under the fingerboard


Brent

Neither David, for my Guitars,
The way I do it provides a means of quickly and without tools, setting string action to suit the player or allow for seasonal humidity changes or string gauge changes.
It is generally accepted that string height at the bridge is a major factor in driving the soundboard, this way the saddle height remains constant.
I use an A frame type brace to stabilise the headblock to UTB area.
I am just finishng up two spanish heel nylon string guitars now btw

Thanks for the opinions, everyone.

Sounds like my line of thinking was about right. Box deformation is the main problem. Hopefully Ervin will wander by and give us some tips
I wonder if his use of laminated sides significantly affects the stability of the box, due to their stiffness? I think there was a mention of using a bit less of a dome to the back, to give it less room to stretch itself flat over time, although I can't find it now. I've also considered using a back bracing pattern that involves more longitudinal support to help prevent that.

I think I will try an integral neck on my next guitar and make judgements based on the result. I don't plan on ever doing spray finishing, so that's not a problem. I'll just be sure to hide glue the back on incase I need to peel it open in the future and twist the headblock back.

But for now, I should get back to work on the current one instead of just reading and planning all day Humidity has been at a steady 45-50% for several days now. I think I'll call it low enough and finally start the box closing sequence after a few more days for the plates to equalize

I'm a little reluctant to join this thread, as I build steel string acoustics with a Spanish heel, and don't feel a strong need to defend it to anyone other than a client, who is usually quite happy to accept it as a point of differentiation on a quality hand-built versus a factory-run instrument. I wouldn't want to be building low-margin guitars on a volume basis with a Spanish heel, but quite comfortable with it in my custom-built operation.

There are many reasons for guitars requiring neck resets, but I would suggest that one common reason is "movement". Anyone working with wood understands (or will soon learn) that its dimensions change with changes in moisture content, and that moisture varies continually with ambient relative humidity. Furthermore, movement in wood in UNEQUAL along its three structural directions. Tangential movement (e.g., across a flat-sawn surface) is usually somewhat greater than radial movement (e.g., across a quarter-sawn surface, and both are MUCH greater than longitudinal movement (along the grain). Now, give some thought to the effect of movement in a joint assembly where the components are not all aligned in the same direction.

I think I'll stop there, but it gives you some insight on how I see the world. Ultimately, I think that there are many ways to build excellent guitars -- all have issues that must first be understood, then overcome.

I believe it's the design of the neck block. (saying "I believe" protects me from lidigation doesn't it?) The "pound of plywood" neck block is designed so the bottom of the block (the back of the guitar) can easily roll out, changing the neck angle. This makes their easy to adjust neck attachment seem desirable. I've seen other builders use similar shaped neck blocks, but with carbon fiber butresses and stiff rims to keep stuff in place.

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Hey Tim,
No need to defend using a Spanish heel as far as I am concerned.
It's what happens from there that matters.
If the rest of the box is built as a standard X brace martin clone.........reset needed eventually.
The headblock is really just a means of transferring neck loads into top and back plates

Fillipo, I think Alan is agreeing with your position, you are just misreading his post.

My method is nothing radical, and it has served me well.
A few points: the A brace butts the upper X and is inlet into the neck block. It doesn't have to if it butts it also.
Laminated linings, very stiff!
The straight M&T can be glued or screwed, customer choice, or mine.

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Just because there hasn't been much interest in this topic, I'll add my two cents....HA

It's clear that we're deep into strongly held beliefs on this topic, so I'll try to express my views in a circumspect manner.

I'm a relatively new builder, and, given the techniques and jigs I use, I'm not 100% certain of the precision of my neck angle. As such, I've found that a mortise and tenon bolt on neck gives me a LOT of piece of mind in terms of being able to set the neck, and view how it's all going together, then make some adjustments. It also has some real advantages in terms of making the neck straight, and fit and finish crisp, since you finish the components separately, then attach for final assembly.

My first four guitars were done with dovetail necks. I got very frustrated with the precision necessary, and the intolerance of slippage in one axis when trying to adjust a different one. Fix this, break that.....
I've never attempted a spanish style neck on a steel string guitar, nor do I anticipate it in the near future. So I can't comment on that. Based on zero experience, it seems to be an unfoirgiving way for a novice to build a guitar.

For novice builders, think that the M&T bolt on neck is a very strong and approachable way to build the neck joint. I'm going to keep using it.

Almost done with my first build (just started a thread actually where you can view some pictures). It's a set neck and I will definitely be switching over next time around. I haven't compared my job to a pro that uses the method, but I believe I could get a much cleaner look with a bolt on neck. I had very tight slots in the neckblock for the sides to insert into but as you can see in the images, it's not nearly as clean or seamless as a bolt on could've been. It was not a short process. I sure don't think its any time or material saver!

The biggest reason for me to want to make a bolt on neck next time around though is to plan for future repairs. It's a shame to think that if this neck ever warps that it will practically be garbage and not worth the expense of trying to fix it.

Also, spraying is a little more difficult I'd imagine and while buffing and polishing I sure wished they were two separate components. Oh- and I still have some leftover compound from buffing to dig out of the crack inbetween the body and neck.

I built a few of those around 1980 and they are still doing fine. I still own one, and I played another a couple of years ago.
I wouldn't build that way today, though.

John

If by slipped you mean lift the back off and adjust the neck by pushing the block back then yes I have and it was a real PIA. I can have a dovetail neck reset in less then half the time. The biggest issue I had in doing that method was preparing the foot since it is at a different angle and must be reset to mate with the back. Of course with a bolt on sometimes you don't even need to take the neck off as you can just floss is with some stiff sand paper.



Ok cool, that's good to know.

BTW have any of you used the wedge method for your Spanish heals? There may be a formal name for this joint but if there is I don't know it. Basically you cut a larger mortise for the sides to slip into the block and then press wedges in to secure them in place. I don't even know if glue would be necessary with this method. I'm thinking of doing that on my next classical build.

Jose Romanillo's wedge solution.

http://www.youtube.com/watch?v=5Z51O6yn1m8

And a thread on another forum with some pictures.

http://www.acousticguitar.com/ubbcgi/ul ... 142#000001