Spanish heel

[gitnoob]

I just found out that the steel-string I'll be building this summer in a class will be built with a Spanish heel.

That actually appeals to me since it seems more robust than other neck joints, but the downside is obviously the inability to do a neck reset down the road.

So that got me wondering.... Is there a way to build a guitar such that it is both responsive and will never need a neck reset?

What techniques would you use?

I figure that Spanish heel + reverse kerfing + flying buttress between the neck block and sides + a box around the bridge plate would probably last a couple hundred years.

[arie]

consult your somogyi book(s). what would ervin do?

[Brackett Instruments]

I'd find another class. Neck resets aren't usually needed because the neck joint failed, or the neck block moved. They're needed because of bellying on the top. If you make the top stiff enough to not ever belly it won't sound good. Things like stiffer sides/kerfing, flying buttresses will only make slipping the neck block to correct the angle more difficult when it becomes necessary in the future. I prefer dovetail neck joints (a whole 'nother topic), but I know how to reset them.

IMHO using a spanish(integral) heel on a steel string is like welding the wheels onto a car. Steel strings have amost twice the tension of nylon strings. The lower string tension is why spanish heels are OK on Classical guitars.

[charles Tauber]

Originally Posted by Brackett Instruments

I'd find another class. Neck resets aren't usually needed because the neck joint failed, or the neck block moved. They're needed because of bellying on the top. If you make the top stiff enough to not ever belly it won't sound good. Things like stiffer sides/kerfing, flying buttresses will only make slipping the neck block to correct the angle more difficult when it becomes necessary in the future. I prefer dovetail neck joints (a whole 'nother topic), but I know how to reset them.

IMHO using a spanish(integral) heel on a steel string is like welding the wheels onto a car. Steel strings have amost twice the tension of nylon strings. The lower string tension is why spanish heels are OK on Classical guitars.

Having made a number of steel strings with Spanish heel construction, and having seen what happens to them when they are 15, 20 and now 30 years old, I think the above advice is pretty accurate.

I've also used both dovetails and Spanish heels on classical guitars. Frankly, I don't see any advantage to using Spanish construction from a structural/sound point of view when one considers longevity.

In my experience, the reverse kerfing doesn't add much, one way or the other.

In the 1970's, Charles Fox taught students to use a Spanish heel construction on all steel strings. He added a piece of veneer on the inside of the top covering the entire upper bout above the transverse brace and the interior portion of the heel was "U" shaped to increase stiffness/strength. The problem is creep over time, and the eventual sag into the soundhole necessitating a neck reset that isn't possible. These days, I believe he teaches students to use mortise and tenon joints - that seems to be the future, with neck angles that can be altered with the twist of a screw, making neck resets a thing of the past.

I guess, one of the questions is what do you want from your guitar making course? Are you planning to make just the one instrument, or is it to be the first of many? Are you looking to learn the latest methods, or traditional methods? If the course is otherwise a good one, you may learn many valuable things unrelated to the type of neck joint used and it may still be well worth attending. (If you made another, you could, if you wanted, learn to include a dovetail or mortise and tenon.)

Out of curiosity, who is teaching the course? How have their 20 or 30 year-old instruments held up - do they need neck resets? Just a few thoughts.

[gitnoob]

Originally Posted by charles Tauber

In the 1970's, Charles Fox taught students to use a Spanish heel construction on all steel strings. He added a piece of veneer on the inside of the top covering the entire upper bout above the transverse brace and the interior portion of the heel was "U" shaped to increase stiffness/strength. The problem is creep over time, and the eventual sag into the soundhole necessitating a neck reset that isn't possible.

Interesting -- I would have thought that would be a fairly robust way to build, and the veneer (or a wedge) between the neck block and transverse brace was something I wanted to try.

Seems like a flying buttress should mitigate the tendency for the neck to sink into the sound hole.

Out of curiosity, who is teaching the course? How have their 20 or 30 year-old instruments held up - do they need neck resets? Just a few thoughts.

He's a local luthier who mostly builds classicals, but I'm happy to learn his techniques and then learn something different elsewhere. I asked him about the neck reset issue, and I think his response was something like the need for a reset should be delayed due to the nature of the Spanish heel, and that other methods were factory-driven short-cuts.

As long as you can delay the need for a neck reset for something close to the lifetime of the owner, that should be good enough.

[charles Tauber]

Originally Posted by gitnoob

Interesting -- I would have thought that would be a fairly robust way to build,

As would have I. But, Charles Fox changed construction methods for a reason, and my experience seems to suggest that it isn't likely any more robust than other methods.

Seems like a flying buttress should mitigate the tendency for the neck to sink into the sound hole.

Seems so and a number of builders have gone that route. What may not be known for some time is whether or not that really solves the problem or simply creates new ones elsewhere. Seems the current direction is for many builders to make a rigid frame, by one means or another, to resist the stresses and use very light top and backs plates.

I asked him about the neck reset issue, and I think his response was something like the need for a reset should be delayed due to the nature of the Spanish heel, and that other methods were factory-driven short-cuts.

My dovetailed guitars aren't as old as my Spanish heel guitars, so I can't comment on any greater longevity for one over the other before needing a neck reset. As for the "factory-driven short-cut", I used to believe that as well. I don't anymore. I can hear no difference in sound quality between one neck joining method versus the other, nor have my customers. But, each of us have our own religious convictions on one matter or another.

Regardless, I make a cutaway that has no space for a neck joint. Short of a bolt-on or David Russell Young style epoxied butt joint, it requires a Spanish heel. So, I continue with it on those instruments and will incorporate stiffer sides and a flying buttress or A-frame.

As long as you can delay the need for a neck reset for something close to the lifetime of the owner, that should be good enough.

Guess it depends upon what one's intentions are for the longevity of one's work. Do you plan for the guitars you make to last 10 years, 20 years, 30 years, 100 years? Guess if your customer is The Who, longevity doesn't enter into it.

[gitnoob]

That's a beautiful guitar. I can see why you chose a Spanish heel.

I've seen a similar deep-cutaway guitar that used a dovetail and a shortened transverse brace. The neck started sinking into the sound hole after about 10 years.

[Alan Carruth]

You have to understand that the Spanish method of building on a solera, which more or less foces you to use some version of the Spanish heel, is also a 'mass production' method, albeit one that uses hand tools. The fixture of the solera ensures proper alignment of the neck, and each worker in a shop could switch of between multiple fixtures that could be clamped in a vice, and removed to allow glue to dry while another instrument is worked on.

I'm another of the builders who started out making Spanish heels, and switched to plug-in necks for their repairabilty. There are ways of stiffening up a wooden structure to increase it's resistance to creep, but there is no way to eliminate the problem. Eventually, no matter what you do, it will jump up and bite you. Even classical necks pull up in the long run.

I have recently started building with a 'constructed' Spanish heel that is, in some ways, the best of both worlds. Basically, I fit a mortice and tenon with the correct geometry, and glue them together with a 2mm spacer in between to form the heel and block, with the spacers providing the side slots. This is then shaped up like a Spanish heel, and used in the same manner on the solera. Using this method the neck can be steamed off in the usual way later if need be, but all of the angles are taken care of up front, as they are with the traditiional Spanish construction. An additional advantage is that the side slots are accurate, smooth, and uniform, and the end grain of the inner surfaces can be properly sized with hot hide glue before the sides are plugged in, which should make things stronger. I first used this on a harp guitar, with a bolt-on neck, and have since used it on classicals.

[gitnoob]

Originally Posted by Alan Carruth

Using this method the neck can be steamed off in the usual way later if need be...

That's an interesting approach. The neck block on some of Charles Fox's guitars also emulated a spanish heel.



Is there a reason you glued the M/T vs using bolts? How does the future repair person know how to steam it off? Does it have a gap past the tenon at the same location as a dovetail would?

[Alan Carruth]

"Is there a reason you glued the M/T vs using bolts?"
Umm, habit?

" How does the future repair person know how to steam it off?"
You tell them, via a note with/on the guitar.

"Does it have a gap past the tenon at the same location as a dovetail would?"

Yes, under the 13th fret.