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In all of the stuff I've read, I am instructed to make my solera with a sloping neck board that ends at about 3mm at nut location, and then the instructions call for a neck to side joint that is 90* to the top of the neck.  Then as I understand my reading, which includes many threads in the archives, the neck angle is actually set with the foot.  Then someone else says the neck should be set some other way.  Hmmm!  How to choose.

I have decided to use the Romanillos style wedge, because I think it makes the most sense, and would be much easier to execute and offer great strength, but I still wonder if I'm not going to put stress on the sides when setting the angle.  Is it going to fall close to the angle created by the 3mm slope?

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Waddy

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Another thing on the same line.

When you cut the shelf for the top to be glued to the neck, no one ever seems to allow for the dip that is going to exist with the negative neck angle.  Does that stuff all just fall together?  I know I'm talking about very small angles, An eighth of an inch in about 13 inches is not a big angle, but it does seem that it would create a dip.  Does setting the neck and gluing on the fingerboard clean up variances in angles?

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Waddy

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Hi Waddy
3 mm negative neck angle sounds like alot.
I've only built 2 guitars myself so I'm no expert.
I've trialled and errored this a bit, however.
Both guitars have been built with no soundboard radius.
Guitar 1 was built with no negative neck angle, and I discovered the string height to be extraordinarily high at the bridge.
I think you'll find the same thing with 3 mm negative neck angle.
I read somewhere that flamenco guitars are built with 4 mm negative neck angle, so I built my next guitar so.
And this causes the opposite problem, with the strings to low at the bridge, and too high off the fingerboard at the 12th fret making the guitar difficult to play.

If I assume to build the soundboard flat I'll get about 2 mm worth of soundboard flex at the bridge when the guitar is strung up since thats what I got on the last 2 guitars.
If I build 2 mm worth of negative neck angle in and incorporate the soundboard felx in, that will be about right.
I'm going to err on the side of caution with my next guitar and buiild in 1 mm worth of negative neck angle, still building the soundboard flat.
Unless someone tells me otherwise...lol.

If you build your soundboard with a radius its going to affect the amount of negative neck angle.

I'd draw a full sized drawing of the guitar and add your soundboard radius into the mix and then I'd add 2 mm worth of soundboard deflection into the mix at the bridge (for when the guitar is strung up), and then determine the negatve neck angle from there.
Perhaps the neck will be dead flat.

If you do come up with a neck angle I'd take a cabinet scraber with 2 square edges and use that to mark out the side slots on the solera once its built.
Double check the cabinet scraper to make sure its actually square.
Set the neck onto the solera, and then put the cabinet scraper at the 12th fret with one edge on the soundboard part of the solera.
Mark a line on the neck there at 90 degrees to the soundboard.
That will give you a line that is at a slight angle to the fingerboard surface.
Thats where I cut my side slots.
That way, when you build the guitar, the sides will set perfectly into the neck slots at 90 degrees to the soundboard and it won't look out of shape.

And then you have to plane the soundboard side of the fingerboard between 12th and 19th fret so there won't be any gaps when you fit the fingerboard.
I worked this angle out using a sliding bevel.

I hope this helps.

cheers,
claire

Thanks for the pointers, Claire.  I do plan on doming the soundboard in the lower bout.  I am using the Romanillos plan for the guitar.  My solera is scooped to about 4 mm to allow for springback after I glue my fan braces.  You are probably right, though, I need to make some determinations from the drawing rather than following what I read.  Unless what I'm reading is right.  the 3mm came from the Courtnall book and also, I think, from Cumpiano's book.

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Waddy

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Gosh i wish there was an edit button.

I need to proof read better.

I said:
"Guitar 1 was built with no negative neck angle, and I discovered the string height to be extraordinarily high at the bridge.
I think you'll find the same thing with 3 mm negative neck angle."

Just ignore that second sentance.

What i actually meant is that i think 3mm neck angle is actually too much and you'll end up with little, or no relief at the bridge.

Sorry about that.
Cheers,
Claire

I too use the Romanillos neck join I don't set my neck angle until I glue on the back. It's not done on the solera.

When I'm ready to glue on the back I clamp it into place and use a series of shims at fret one and at fret twelve (fingerboard clamped to the neck) in conjunction with a straight edge to simulate my desired string height and then gently pull the headstock forward or push it back until I achieve a straight edge (string) height I desire at the bridge location (10mm). I then mark where the heal/foot is on my back seam reinforcement strip (inside the guitar). I also massage the fingerboard while the guitar is held in this fashion to account for any dip.

When it's all correct I disassemble, cut the center seam strip to my mark then glue it up pulling everything into position and clamp in place.

As to stress on the sides, I'm sure there is some but they really aren't moved too far from where they fall naturally.

Sounds very complicated but it's not so bad really. Nice thing is it's changable to give almost any desired string height anywhere along the path.

BTW this is the method tought by David Schramm. It's illustrated pretty well on his build your own Hauser cd, available on his website.

Waddy - If you dome about the amount suggested by Courtnall, and set the neck forward about 2mm, things come out pretty good. I do try to put the extra relief in the shelf of the neck cut out for the top, so that the top doesn't get stressed when I clamp the neck down to the solera.

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Jim Kirby
kirby@udel.edu

[QUOTE=RCoates]I too use the Romanillos neck join I don't set my neck angle until I glue on the back. It's not done on the solera.



When I'm ready to glue on the back I clamp it into place and use a series of shims at fret one and at fret twelve (fingerboard clamped to the neck) in conjunction with a straight edge to simulate my desired string height and then gently pull the headstock forward or push it back until I achieve a straight edge (string) height I desire at the bridge location (10mm). I then mark where the heal/foot is on my back seam reinforcement strip (inside the guitar). I also massage the fingerboard while the guitar is held in this fashion to account for any dip.



When it's all correct I disassemble, cut the center seam strip to my mark then glue it up pulling everything into position and clamp in place.



As to stress on the sides, I'm sure there is some but they really aren't moved too far from where they fall naturally.



Sounds very complicated but it's not so bad really. Nice thing is it's changable to give almost any desired string height anywhere along the path.



BTW this is the method tought by David Schramm. It's illustrated pretty well on his build your own Hauser cd, available on his website.[/QUOTE]

Ron:

Thanks. I have Schramm's CD, and I like it.  It does, however say to use Courtnall's solera plan, which is pretty much why I did, so then I started wondering about the stress on the sides cutting a 90* slot with a degree or so of negative neck angle.  The setting part I understand fine, I think.  It makes sense to me, anyway, but all this moving the neck around after it is attached to the sides seems like it would stress the sides at the joint.  Maybe I'm concerned about stuff that is too small to worry about.

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Waddy

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[QUOTE=jtkirby]Waddy - If you dome about the amount suggested by Courtnall, and set the neck forward about 2mm, things come out pretty good. I do try to put the extra relief in the shelf of the neck cut out for the top, so that the top doesn't get stressed when I clamp the neck down to the solera.[/QUOTE]

That makes sense to me, too.  I figure I should worry about this stuff before I actually get there.  I like to be comfortable with the process and be sure I actually understand why I'm doing stuff the way I'm instructed.

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Waddy

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Does he mean cutting the slot at 90 degrees to the fingerboard surface of the neck.
Or does he mean cutting the slots at 90 degrees to the soundboard?

Cheers,
Claire

I build a Romanillos style guitar and also have attended the Jose Romanillos class last year in Siguenza, Spain and will again this year. Here are a few notes of the Romanillos method:

For our solera we did not use a dished workboard but rather the section that is the lower bout was built up 5mm and then dished in an ovoid shape that tapered to level with the top portion of the workboard at the main crossbar with the deepest part of the dome (where the bridge is) being 3.5mm. The top when braced is cut to final shape to the interior dimension of the plantilla outline. The side then when bent were clamped in position around the plantilla of the top with the ledge of the dome of the top helping to provide stability for clamping the sides against the top.

The relief of the top radius means that when the guitar is taken off the workboard that the sides will project past the top by about 2-3mm. This is a very different method than the typical cutting the top oversized, then resting the sides on the top and then afterwards trimming the top even with the outer profile of the sides.

By raising the dished part of the workboard it also helps to account for the drop in the sides caused by the curve of the top.

As far as the neck, the slots are 90 degrees to the sides. The neck does have a negative angle of 2.5mm and when combined with the curve of the top works out well.

As to the wedges, in the past the slot used a wedge (and slot that would taper from 10 to 12mm so that when the wedge is inserted, it would draw the sides tight with the heel forming a very nice tight neck joint. It has always been a trial and error process when you just use a slot the thickness of the sides as it needs to be tight enough to not have a gap but not enough to split the side or loose enough to show a gap.

Last year at the Romanillos class we tried a different way to wedge and that is two opposing wedges in a parallel slot. By making the slot an even 10mm it is easier to cut and then equal wedges turned 180 degrees to each other allows an easier fit and still uses a wedging effect to draw the joint tight.

Important when wedging the side, glue is placed on the side of the wedge that is facing the spanish foot/heelblock but no glue is placed towards the side so if the guitar even had to be repaired the wedge could be cut out and a new wedge put back in without changing the neck geometry.

I use the same Romanillos when building flamenco guitars and then just adjust the string clearance by reducing the height of the saddle and by adjusting the relief (on the bass strings) of the fingerboard to the lower action of a flamenco.

Shawn:

That is great information.  I am curious about the way the solera is built up and formed to produce the curve in the top.  This makes great sense, in that it allows the curving of the top in the solera without any artificial support.  Does the top taper back to level at the end block as well, or is that 5 mm lower than the upper bout too (higher on the solera).  I'm trying to get the geometry of the solera.  I see how this would make finding the taper of the sides at the top easier to fit.  I'm gonna have to re-make my solera, or maybe I can build it up with thin wood and smooth it back out.  It is currently dished about 4mm at the bridge, and levels out at about 10 or so mm from the side and tapers up to the soundhole.  I had not allowed for the tapering of the edges of the top.

I also like the opposing tapers.  I had read that thread in the archives, and thought it was a good idea.  Are the wedges cut to account for the V shape of the cutout in the neck joint?  Wider at the bottom, or does he still use a V shaped cutout?

Is there anything you are aware of that tells more about his techniques?  I have the GAL issue with his guitar in it, and the Courtnall book, but didn't know if there was other stuff to read.

That's too many questions, please do not feel obligated to try to answer them.  I will eventually figure it out.  I appreciate what you have shared already.

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Waddy

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Sound Clips of most of my guitars

The lower bout of the solera is made by attaching a 5-6mm layer in the shape of the lower bout (right to the inside of the plan less the outer dimension of the sides) and is then worked to taper to level at the front edge of the lower bout at the main cross bar. At the heelblock area is it is still almost the full height and does not taper much at all as you are really trying to establish the plane of the bridge to nut while setting the dome of the top.

The way I worked this out when making my workboard is the radius of the top is approximately 25' so I used on of the clear acrylic radius gauges that LMI sells and used that for reference as I dished out the lower bout of the applied layer. What is nice about the radius gauge that LMI sells is that it is radiused on both inside and outside edges so it can be used to view the radius of a back on an instrument but also sit across a solera to see what the effective radius of the top is.

Using the LMI radius guage I cut a piece of scrap wood and attached self adhesive sandpaper and now had a way to refine the dish of the applied layer. As I tapered the applied lower bout area I focused on just planing the taper of the layer so it would taper to level at the top of the lower bout first (to establish the plane) and then started to remove material to build in the radius needed with the lowest part being the bridge area.

By using a combination of carving out material and then fairing out the curve using the scrap that was cut to the effective radius, I was able to get that layer to the same depth as if I were building it into a flat solera but still have the raised edge around the perimeter of the lower bout that Romanillos uses.

Because the radius is ovoid instead of a consistent dome as is done on alot of steel strings, there is some tapering at the heel area. I focus on getting the depth of curve just right at the bridge area and consistent to tapering to nothing at the top of the lower bout rather than aiming at some height at the heel area as I do not want much if any taper at the heel.

As far as the opposing wedges are concerned, what we experimented with was cutting the slot in the neck parallel rather than tapered and then let the opposing tapered wedges wedge against each other to fill the slot. We also tried using a neck that was already cut with the tapered slot and using two wedges and that worked as well.

What Jose was thinking about is that with a single wedge, the angle and consistency of the wedge has to be just right to apply even pressure. If the wedge had a bump or a sweep along its face it could bind and not apply even pressure. Note this was all experimenting on what would make it easier for the builder to get consistent results.

Jose has been retired from building for about 8 years now but he is still always thinking of new ways to refine his processes and is trying to pass this on to as many builders as he can. Even though he is not actively building, he still manages to build 3-4 guitars a year and is always working on new jigs or ideas for the class. Some of the ideas such as the opposing wedges he had not even shown his son Liam who does all the building of the Romanillos guitars today.

Shawn - Thanks for all the info on the Romanillos solera.

Ronn - I don't get how the Schramm neck-setting method works with the wedged joint. I use David's method but with regular slots, and it seemed to me that the key to the method is having the sides free to move in the slot during the setting. If they are wedged in, how are things free enough to move, or in fact is there not really enough slip going on to worry about? (I've never remembered to check that in detail while doing it.)

Guessing that the answer is that there isn't enough movement to worry about, I may start doing the wedges - I have a heck of a time getting my slots perfect enough to get no visible gap.

_________________
Jim Kirby
kirby@udel.edu

For years I built classicals using the sand, fit, sand, fit nuisance of getting the thickness of the sides to the slots without a gap and once I tried the Romanillos wedge approach I would never use any other approach. It gives me the consistency I want with the ease of assembly as a bolt-on but still be able to stick to a traditional Spanish foot.

What is nice is I can fit and adjust where and how my sides fit and still adjust them all the way until I drive the wedges home. The wedges force the sides tight against the heel so there is zero gap.

Shawn:

Thanks for the information.  I get a picture that you have a taper from the main brace that tapers up to 5mm at the wide point, then stays at that level around the perimeter to the other side.  Then it is scooped out at roughly a 25' radius that dips 3.5 - 4.0 mm in the center putting the dome in.  Does the dish level out before it contacts the sides to facilitate the gluing of the dentillones?

The only question on the wedges relates to the V shape of the neck cutout - i.e., at the fretboard surface the width across the neck at the 12th fret is say 3mm and at the bottom at the heel, it is either pointed or down to 1 mm or less.  So in that case, the wedges are tapered in two directions.  Is that right?

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Waddy

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[QUOTE=jtkirby]
Ronn - I don't get how the Schramm neck-setting method works with the wedged joint. I use David's method but with regular slots, and it seemed to me that the key to the method is having the sides free to move in the slot during the setting. If they are wedged in, how are things free enough to move, or in fact is there not really enough slip going on to worry about? (I've never remembered to check that in detail while doing it.)

Guessing that the answer is that there isn't enough movement to worry about, I may start doing the wedges - I have a heck of a time getting my slots perfect enough to get no visible gap.[/QUOTE]

Jim-
I've never even considered the need for any movement where the sides join the neck. Perhaps I should. There really is not a great deal of movement (forward/backward rotation) that happens in that location. I couple of mm at worst. The sides can actually move I suppose. Remember the idea is to glue the wedge in only where they make contact with the foot/neck block. The sides are just a press fit.

FWIW I plan to finish the one I'm working on now and then I want to try going to a neck joint similar to that used by Greg Byers. You can see it on his site.

Ronn - I didn't see a detail of the joint there - are you talking about the elevated fingerboard? I hope to get a chance to look at a Humphrey Millenium belonging to our school's guitar professor shortly.

Jim

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Jim Kirby
kirby@udel.edu

[QUOTE=jtkirby] Ronn - I didn't see a detail of the joint there - are you talking about the elevated fingerboard? I hope to get a chance to look at a Humphrey Millenium belonging to our school's guitar professor shortly.

Jim

[/QUOTE]

Go here then scroll down and click on the center picture. I am toying with the idea of the elevated fret board which according to Greg's site is what requires him to build the neck joint in this fashion.

If you get to see that guitar take some good pics if possible and let us know all about it... Pretty please.