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Do any of you know where I can find an authoritative source of information regarding building steel string with a Spanish heel.

I have read Bogdanovich and I have a reference book by Australian Luthier Jim Williams.

Both build guides do not make any reference to setting the neck angle back, in fact it would appear that they are perfectly straight. I also have the Alex Willis book who explains that the neck angle is set by putting a wedge under the neck before gluing to the soundboard, but that just tells me if you have a flat neck and a flat sound board when you remove the wedge everything is just straight !

I want to understand the the mechanics of the Spanish Heel or am I reading it too deeply ?

John

John: Have you considered that the guitar may need a reset sometime in the future???
Tom

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A person who has never made a mistake has never made anything!!!

Most classicals have no back angle .. they dont need one .. sometimes they need negative angle to get the lie of the frets in the correct position, which is usually about 3-4 mm below the top of the bridge .. this allows the proper action at setup, and not have too much saddle showing.

Since almost no one builds a steel sting with a spanish heel, I doubt you will find any text with info on how to do one. You will definitely need some sort of back angle to get the lie of the frets to sit above the top of hte bridge, again for proper action at setup, and not too much saddle showing.

You may need to leave the neck blank thicker as you glue the body together, and then plane the required back angle onto the top of the neck blank prior to gluing the fingerboard on.

If you do go ahead with this, I would strongly advise over-setting the neck a bit .. it will pull forward over time, and if underset, you will have a lot of fun trying to reset it (why we build necks that can be easily reset !!!) ...

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

i don´t have it here with me ATM, but i believe the Alex Willis book (step by step guitar making ?) talks of the spanish heel on steel-stringed guitars - that is, IIRC.

cheers,
miguel.

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member of the guild of professional dilettantes

Thanks for the posts, maybe I should have phrased it better.

I hear what you say about neck resets however there are different flavors of Spanish heel including those that include wedges in the design, it is this type of information that I am looking for.

Regards

John

Whether the neck is integral or bolted on or dovetailed or whatever, doesn't affect how you need to manage your angles to achieve your target string height above the soundboard. One thing I like about integral is that, if you use a headblock extension to the upper transverse brace, it guarantees the fingerboard and upper bout surfaces are coplanar, thus no dropoff or ski-jump after the 14th fret. But if you normally use a 1.5 degree neck angle or whatever, then you need to make sure that upper bout surface is at a 1.5 degree angle to the sides, by some means or another (careful arching of the upper transverse brace, for instance).

Depending on your fingerboard thickness and soundboard arching (or lack thereof) and target string height at bridge, you may or may not need an angle... In Ervin Somogyi's book, he says he goes for 0 angle between the neck surface and bridge spot on the soundboard. i.e. the fingerboard thickness plus fret height plus slight upward angle of strings for proper action minus slight pulling up of the top under tension all work out to his target string height.

Another technique you can use to control the angle is tapering of the fingerboard thickness. If you make it 1/16" thinner at the nut end than at the 12th fret, then the projected string height at the bridge will be 1/16" higher.

Resets are certainly an issue though. I'm not a believer that resets are inevitable (well, they probably are if all you put in your upper bout is a popsicle brace... ), but I'm also wary of building more integral necks just yet, as I am a fan of thin tops and light bracing, and am still learning what is "too flexible" My last one pulled up about 1/8" in the first few days, but fortunately I got the neck angle a fair bit higher than intended, so that actually worked out just about perfectly

HI

Not quite a standard Spanish heal, but similar concept is employed by the UK's Master Builder Stefan Sobell -wionderful instruments that I wish I could afford and do justice to) Scroll down on the page and see the construction pics..

http://www.sobellinstruments.com/en-gb/news/news2009.aspx

Stefan's is called a modified bridle joint and has little to do with a Spanish heel. The block part of the neck is not integral to the rim, which has its own neck block, however thinner than usual. When Stefan's guitars need adjustments, either the fretboard is planned with a back angle, or the bridge is shaved. Possibly both.
Romanillos uses a neck joint similar to what John is inquiring about, I am sure there's at least one video on YouTube. For a steel you just have to set your neck angle right, that's all.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

i just red your first post and you already mention willis´book. sorry for my redundance, that´s what you get when you post half a sleep.

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member of the guild of professional dilettantes

Dennis, I like your thinking about geometry and structure, but the "thinning the fingerboard at the nut" option worries me. Fine tuning the neck angle by planing the fingerboard is certainly a traditional classical guitar building technique. You'll see many classical guitars built by famous makers, commanding very high prices, that have tapered fingerboards. If the guitars are new, the taper is almost always the opposite of what you describe. There are two important reasons for this:
#1 The most pragmatic--if you're aiming for a projection target at the bridge, it makes sense to aim high. If you need to bring your projection down 1 mm, you'll only have to shave 2/3 mm off the end of the fingerboard. On the other hand, if you need to bring the projection up 1 mm, you'd need to shave 2 mm off the nut end. #2 To the extent that things might shift over time, you can assume that the neck would rotate forward. When that happens, you'll need to take material off at the nut end.

Todd, I haven't seen the problem you describe with neck block extensions. I use this construction myself (combined with a "slipper foot"), and I've assumed that it does a better job of distributing the neck rotation stresses towards more rigid bracing. Can you give me more details about the failures you've seen?

These will develop that once you do a back slip to reset the neck. That is one of the main reasons this design is so problematic .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

That is definitely true. When I use an inverted Spanish foot I use a massive UTB and a .090" thick soundhole patch between the soundhole braces with the grain running along the soundboard's. I have yet to see one of my guitars distort. The weak link with an L shaped neck block is the soundhole area, but that is true of most steel strings designs.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

A clearer terminology to describe this construction style is "Spanish foot" or construction in "The Spanish style" as opposed to a "separate" neck construction.
"Spanish Heel" actually only refers to the swooping external portion of the heel which has been now (as compared to the conical heel) been almost universally adopted.
Though many classical builders have moved on to a "separate" neck construction. The "Spanish style" mode still offers the easiest and surest way to set the correct neck angle ("lift") and alignment.
Though generally not used for steel strings, I don't see why, with proper construction considerations, it could not be successfully adopted, especially considering the vastly superior truss rods in use today.
Most builders though I think find handling and finishing separate necks and bodies much easier and more convenient.

Time will be the deciding factor . I have seen a number of Spanish style constructed guitars . They distorted just like the separated neck construction . Of the guitars I saw 2 production and 1 hand made , they bracing structure is similar to modern X brace construction . Age was between 15 and 20 yrs .
Forces applied over time will move things. It is a balance we builders try to walk every time we make a guitar .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I'm pretty sure that David Freeman uses a Spanish heel on all of his steel strings, including a 12 string that I played at the 2008 GAL. He gives lessons and instructions, might be worth sending him a query

http://www.timelessinstruments.com/

I don't see why you wouldn't be able to build a guitar with a spanish style neck joint for a steel string and have an angled neck. My neck blocks are square when I glue them on. My upper face brace is curved, as are my x-braces and lower face braces. Then I glue my sides on, and shape everything to recieve the back. The end result is a guitar with a 1.5 degree neck angle, with a square block. Why couldn't you set up the geometry for a spanish style neck joint the same way?

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Old growth, shmold growth!

The issue isn't that you can do that , you can . The issue is as the guitar ages and the neck rotates , and it will , the resetting technique is to slip the back . This is not an easy technique to pull off and it makes keeping the fretboard in line more difficult. I see no advantage to using this system . Just my 2 cents .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Back in the 70's, I was one of Charles Fox and George Morris's "Earthworks" students. It was a great experience--they were both great teachers and inspirations to me, and even in banjo making what I learned from them 30 plus years ago is still very much a part of my shop routine. The way that they were teaching guitar making--steel or nylon string--was Spanish heel/workboard/no mold. They taught no neck angle built into the mix--the way they arched the tops (flat above the X brace, but falling away to create a radiused top) took care of the action. It worked, and the guitar that I built at the school is still in very playable condition today with no neck set needed. But, I play on very light strings, and the situation could be very different if I played mediums.

Did it work? Yep. Did the method of building make sense for a custom builder? Yep. Was it a good way to teach a very flexible way of building guitars? Yep. Is it a method that I'd recommend for commercial sales of steel string guitars? Nope. Too many variables and too hard to remedy problems as they come along.

Charles and George did stress that options were present to use the same Spanish style construction, slipper foot and all, with a removable neck joint (they were suggesting a spline type joint at the time). I followed that advise on post-Earthworks guitars and it worked well. But I still used the no neck set/top falls away radiusing method and it worked well for me.

Dave

There is a long standing debate among classical makers as to whether the separate dovetail or mortoise and tenon neck joints are less rigid than those built in the Spanish style.
I've never tested this, but I can say that the Spanish construction is extremely rigid.

I think the concept could indeed be successful with steel strings given the right modifications.

John's point about neck rotation in traditional steel strings is well taken, but that may be reflective of the deficiencies present in the traditional dovetail construction.
Something that even Martin has moved well away from with the footed neck blocks that they are now using.

John is correct that Spanish style integral heel/neck joints DO in fact rotate, just as dovetail and bolt necks rotate. When I was up North in Cumpiano's workshop for my tutorial, I asked him about that, and he said the same thing John said, that the necks do in fact rotate, and require resetting by slipping the back, an unnecesarily long and not simple procedure , compaed to resetting a dovetail.
Basically you have to slice the back of the guitar away from the heel, slip the neck to the correct angle, reglue it, trim away the ecxess back, rebind, and refinish it. A lot of work.
Is it worth the percieved improvement? IS it an imporovement? I'm not convinced, with all the great sounding dovetail and bolt-on acoustics out there.

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Old growth, shmold growth!

when a joint like a dove tail is joined and glued , it will rip a guitar apart before failure so at what point do you look at strength and stiffness. The art of Joinery evolved over time because of the strength of the glues. Joints like mortice and tenon and dovetails evolved as mechanical joints that used a glue to help freeze them. Mechanical advantage is where the joint achieved its strength.
As adhesives improved the glue became the strength of the joint as the shear strength began to exceed the strength of the wood . Joint integrity is more important that anything and yes I think a Spanish joint is as strong as you can get but it makes resetting the guitars geometry very difficult and Dovetail joints have proved an advantage for this . Sound wise , I doubt if 99 99/100% of the people could hear a difference.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I'm not advocating that anyone ought to build steel strings commercially with Spanish style construction but that this principle could be adapted with (as I wrote) modfications to make it workable. Mostly modifications to the upper bout structure which tends to collapse in over time and is the real culprit in all forms of neck rotation.

"Slipping" the block is an outmoded and destructive technique in correcting the neck angle of a Spanish style guitar.
Much better results can be achieved in most cases through planing and retapering the fretboard .

I just reset the neck of a 12-string guitar with the Spanish foot construction. I have no idea why the luthier chose to use this method on a 12-string none the less except that today 40 years later he's an accomplished classical builder so it's probably the technique he was comfortable with. This guitar had already been slipped one too! So the only choice was to saw the neck right off and convert to a bolt on, very expensive operation. I've done this operation 3 times now and it works quite well.

The amount of neck resets I've done on nice guitars and having seen Spanish 'feet' need a neck reset I'd never consider using such a method on a Steel String guitar. Heck I have not used that method on classical guitars in ten years

But to answer the OP question, I do not know any authoritative voice on the subject as far as steel string guitars are concerned but there is plenty of info on classical guitar construction which essentially is the method you want to use. The wedge method will open the top up a bit by stressing the sides setting the neck angle when the top is glued down. That will work just fine, other wise just cut your side slots on a slight angle and adjust the top and foot of the block to the appropriate angles.

If you do use this method I'd say you definitely want to angle back and shoot for the high side of acceptable string saddle height to facilitate action adjustments in the future. A truss rod is not a device intended to correct action heights due to string tension and deformation. It's only good for setting playable action preferences and dealing with minor changes due to humidity etc...

I believe Pimentel & Sons use an integrated neck block as you've described. You might give Rick a call and inquire about it.
When I was at his shop a few years ago, he was more than happy to lend all the advice he could about the process they use to build guitars.

http://www.pimentelguitars.com/index.html

Either way, good luck.

Dave