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Yesterday Rick Turner was the guest speaker at our guitar club meeting. He brought several instruments and spent the evening answering questions from instrument making to sound amplification to the business of guitarmaking.

One of the things that Rick talked about that really made sense was stiffening the fretboard with a couple of 1/8" x 1/8" graphite "rods".

This comes from a Kenny Hill observation that the first line drawn in basic guitar design is that of the string(s). All other lines are drawn 'down' from that. Next would be the top of the frets - the relationship between the bottom of the strings and the top of the frets being crucial. According to Rick's thinking, stabilizing, i.e. reinforcing, the fretboard would be more effective than reinforcing the next level down, the neck.

Interestingly, there was an upright bass maker at the meeting, who said that fingerboard (no frets on an upright bass) reinforcement was used to good effect in upright bass making! (Some pretty serious fingerboards there!) In the case of 21st century ebony fingerboards over Chinese maple necks; the maple moves, but the reinforced ebony doesn't. 

Rick used 2 graphite 'rods' on the guitar that he sent to Antarctia (minus 60 degrees and single digit humidity). It was a guitar with an adjustable neck with the fretboard floating above the upper bout. Apparently it worked like a champ.

Hard to argue with empirical evidence.

Another place Rick uses graphite is on top of the back reinforcing centerstrip. It stiffens the back, and, he reasons, improves the reflective properties of the box, which is good for projection. This is in contrast to the 'flexible back' school of thought, where the back moves in concert with the to to amplify the sound. His point being (and that of Ervin Somogyi at last summer's GAL convention Listening Test seminar) that when most people play steel string guitars, they hold the guitar against their body, thereby dampening away the harmonic amplification effect. The eye-opener for me was that if the customer wants a guitar that projects, we build it with a stiff back; if he/she wants a sound that envelops the player, we can do different things, like add a soundport.

It was a very interesting evening.

Larry

 

That is interesting. What "club" are you speaking of.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

I may be wrong but he might be talking about NCAL

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Tickle your guitar daily, and it'll tickle you back.

The guitarmaking club is the String Instrument Makers of Southern California (simscal.com) We're in Orange County (CA) and the Los Angeles South Bay - Torrance, Redondo Beach, etc.

We have about 25 members of mostly amateur steel string and classic guitarmakers. Many of us are graduates of the Orange Coast College (OCC) guitarmaking program. This year, we will have a couple members showing at Healdsberg. – Jim Ellsberry and Monica Esparza. Last year, Jim, one of our officers showed his arch tops at the Newport Guitar Festival; two members - Monica and Chris - attended Jose Romanillos’ guitarmaking seminar in Sequenza, Spain; and several other members attended the Guild of American Luthiers convention in Tacoma. Some of the membership are really into guitarmaking.

 

We also teach guitarmaking, both steel string (Bob Mattingly method) and classic (Jose Romanillos method) guitarmaking with about a half-dozen students in each group. The steel string class is taught by Eric Nichols, who taught guitarmaking at OCC for 10 years. Monica, who, in addition to being an OCC guitarmaking graduate, has taken Jose Ramanillos’ guitarmaking seminar for the past 3 summers, teaches the classic guitarmaking group.

 

In addition to this, we have quarterly meetings, which have included some excellent “hands-on” demonstrations”, such as, a French polishing demo in 2005, featuring Ron Fernandez, where everyone in attendance French polished a piece of spruce or cedar. In 2006, we had an inlay demonstration, featuring Jimmi Wengert (Kathy’s daughter) and R. C. Allen, and also a hands-on intermediate rosette-making demo, where attendees routed the rosette channel and glued-up a few rosette-sticks into a simple pattern. Et cetera. Equally important, these meetings are social get-togethers, an opportunity to “show-and-tell” our latest projects, share our latest “discoveries”, and generally hang out with other guitarmakers.

 

Great information Larry! I'll have to try stiffening my fretboard on my next project. I've always been a big believer in stiff neck/fretboard equals more sustain and vibration from the neck. Thanks for that tip!

Also, how was the Centerline finder received by others in the group? Take care!
Tracy

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Tracy
http://www.luthiersuppliers.com

Argh!    So much going on at work that I forgot about this meeting. It would have been nice to attend and meet people.

Philip

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aka konacat

If you think my playing is bad you should hear me sing!
Practice breeds confidence and confidence breeds competence. Unfortunately, I'm stuck in practice.

Of he does
LA composites

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Jim Watts
http://jameswattsguitars.com

A few years ago, I was visiting Rick Turner's shop and actually saw that
Antartica guitar. I wish I would've know it was going to be such a big deal
research thing.

sounds very interesting. How exactly does he go about installing the rods
in a fingerboard?

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Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

Mike,

'Rods' was a poor choice of words for lengths of graphite reinforcement stock that are 1/8" x 1/8" square.

Rick used 2 and they were laminated into 1/8" x 1/8" channels cut in the fretboard. That puts them about half the thickness of the fretboard, with the top of the channel pretty near the bottom the the fret slot.

What did he say was the advantage of putting 1/8" square rods in the fingerboard as against the 1/8 x 3/8 rods that many of us put in the neck under the fingerboard. The 1/8 x 3/8 rods will stiffen the system much, much more than the smaller rods in the fingerboard. Does he use the neck graphite rods as well? If so the contribution of these extra small rods in the fingerboard would seem to be minor in comparison.

Just wondering.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

I have tremendous respect for Rick Turner, but I have to build on the heels of what Colin mentions.
Sure, a stiffer fretboard is better than a weaker one, but this whole concept of viewing individual parts as individuals instead of part of a system or unit makes little sense from a structural perspective. Once a fretboard is glued on, it becomes part of the overall unit. In a sense, it is now one with the neck. It is no longer a seperate piece. I know that it may have a different modulus, and has the *potential* to behave differently than the neck wood, but once they are glued together, some of that potential is locked out. Certainly 1/8"x3/8" CF rods in the neck are going to provide more stiffness than the 1/8"sq CF rods in the fretboard wood. Once it's all glued together, they work together, not as seperates.
The theory that the strings are the first element and the fretboard the second is interesting, but I'm not sure it's truly quantifiable, nor appropriate to think in those terms. Again, it's a system, not a group of individual parts.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Colin/Don,

Rick is an OLF member and may respond, but my understanding (and this is my interpretation) is that he uses an adjustable neck joint and free floating fingerboard extension. Rather than use a wooden neck extension under the end of the fingerboard like I do (copied from Colin) Rick uses the CF rods which are embeded into both the neck and fingerboard. This is part of Rick's system including adjustable neck joint, minimal neck block and cf buttress braces etc etc.

Rick does some very inventive and innovative stuff and it's fom him, Mike Doolin and Howard Klepper that I have adapted and evolved the way I believe in making the upper bout area as free as possible to contribute to the complexity of sound I am seeking and don't beleive for one minute that it is an acoustically "dead" area - unless you brace it that way.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

compression fretting has been the standard way to stiffen and keep straight a f-board for a while, so I think Rick is correct to look at the fingerboard to stiffen a neck.

since compression fretting takes some time and a high skill level, Ricks idea might be just the tickett.


Matt

[QUOTE=Dave White] Colin/Don,

Rick is an OLF member and may respond, but my understanding (and this is my interpretation) is that he uses an adjustable neck joint and free floating fingerboard extension. Rather than use a wooden neck extension under the end of the fingerboard like I do (copied from Colin) Rick uses the CF rods which are embeded into both the neck and fingerboard. This is part of Rick's system including adjustable neck joint, minimal neck block and cf buttress braces etc etc.

[/QUOTE]

Right Dave, now it makes more sense, if he is using the CF to reinforce a floating fingerboard without a neck extension then CF in the FB makes sense. If, like us, the floating board is glued to an extension of the neck then the ones we use are all that is necessary.

It's all clear now.

As Don says, once glued on the FB becomes an integral part of the complete neck system and can't be viewed in isolation.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Apparently I missed the free-floating fretboard over the body part. Now it makes sense.

On a standard acoustic, I'm not sure there's a lot of benefit compared to CF in the neck shaft. I have used 5-piece laminated necks with CF in the shaft on my last several guitars, and the necks are stiff as rocks. Perhaps too stiff!
If you're wanting to get a stiffer fretboard, look to John Watkins idea of making the fret slots match the curve of the surface, which leaves more wood under the slots in the center of the FB.
Matt, again, it's all about the unit and not as much the indivual parts. Compression fretting introduces forces into the fretboard and neck as a unit, not just the fretboard. Gluing them together makes them one unit, not two seperates. Folks gotta stop thinking of them as seperate parts once they're glued together. If you stiffen one, then you stiffen the other.

The whole is equal to the sum of its parts. - Using 1/8" to stiffen a fretboard won't work better than using 3/8" to stiffen the shaft and extension. It's simple mathematics. Don't they teach Statics and Strength of Materials in schools anymore?
Colin is right.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Don Williams wrote -
"If you're wanting to get a stiffer fretboard, look to John Watkins idea of
making the fret slots match the curve of the surface, which leaves more
wood under the slots in the center of the FB." (sorry - haven't figured out
how to do the pink box thing).

Don &/or others - could you tell us a little more about this and how a curved
fret slot might best be cut over a radiused fretboard. I'm wondering about
how it could be done with consistant results.

thanks, john

[QUOTE=johnfgraham]
Don &/or others - could you tell us a little more about this and how a curved
fret slot might best be cut over a radiused fretboard. I'm wondering about
how it could be done with consistant results.

thanks, john[/QUOTE]
The way it is done with consistancy is to pick up the phone and call a CNC guy. I can't imagine the jig that would be required to "roll" them through a saw blade.

On the fingerboard vs neck reinforcement thing: In my earlier guitars, I toyed with the 1/8 x 3/8 carbon rods sticking proud of the neck and aligning into grooves in the fingerboard. I only did it on one because I had a alignment issue and had to pull the fingerboard. Trust me, you don't ever want to have to pull a fingerboard that essencially is double splined with carbon. That was enough for me to abandon the idea all together.

[QUOTE=johnfgraham]
Don &/or others - could you tell us a little more about this and how a curved
fret slot might best be cut over a radiused fretboard. I'm wondering about
how it could be done with consistant results.

thanks, john[/QUOTE]

Constant-depth fret slots are not that difficult to do if you are cutting slots by hand (not that I want to do that again!). I recall that the old Lewis fret-slotting jig had some instructions for this (it's now the LMII jig, I think). Anyway, you could always cut too-shallow slots with your power saw and then deepen them by hand- a simple stop clamped to your hand fretting saw blade can set the depth.
It's not necessary to turn the work over to a robot (CNC) every time we find a problem! Come on guys, what are we here, men or mice?

Cheers

John

I'm a mouse. Give me a cnc!

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Yeah!  Squeak Up!

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

[QUOTE=JohnAbercrombie] [QUOTE=johnfgraham]
Don &/or others - could you tell us a little more about this and how a curved
fret slot might best be cut over a radiused fretboard. I'm wondering about
how it could be done with consistant results.

thanks, john[/QUOTE]

Constant-depth fret slots are not that difficult to do if you are cutting slots by hand (not that I want to do that again!). I recall that the old Lewis fret-slotting jig had some instructions for this (it's now the LMII jig, I think). Anyway, you could always cut too-shallow slots with your power saw and then deepen them by hand- a simple stop clamped to your hand fretting saw blade can set the depth.
It's not necessary to turn the work over to a robot (CNC) every time we find a problem! Come on guys, what are we here, men or mice?

Cheers

John[/QUOTE]

John, I think you might be misunderstanding what was asked. The fret slots in question are the same shape as the fretboard. For example, if you have a 12" rad board, the bottom of the fret slots are also 12". So they are the same depth from edge to center to the other edge.
Now, if you weren't misunderstanding and this is indeed what you were thinking, I'd be curious as to how you would do it by hand.

How do you guys get relief if your necks are so stiff?

Relief.......?


That's the trick, isn't it?!!

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Don said, Certainly 1/8"x3/8" CF rods in the neck are going to provide more stiffness than the 1/8"sq CF rods in the fretboard wood. Once it's all glued together, they work together, not as seperates.

One reason that putting a stiffener in the fb is more effecient is that the vast majority of the stiffness of a beam comes from the outer surfaces, in this case, the fingerboard and the back of the neck.  I'm not an engineer and don't know the math but the area where most people put those 1/8" x 3/8" bars in the neck is pretty much right on the "nuetral axis" of the neck, an area that contibutes relatively less to the stiffness of the neck.  In fact, I've been wanting to test the idea of cutting slots in that location and leaving them open as a way to reduce weight.  My guess is that the neck would lose very little stiffness in the process.

The fb is stressed in compression and the back of the neck is in tension.  The bulk of those forces are felt at the outer surfaces and decrease essentially to zero where the forces switch from compression to tension.  In a symetrical beam, that would be the mid point.  In a neck, the shape of the neck and the extra stiffness of the fb mean that the nuetral axis would move toward the back of the fingerboard.

From a structural standpoint, I'm curious why a super stiff neck is needed when you have a truss rod.

From a sound standpoint, I'm really curious.  When I put carbon reinforcement in my necks, it seemed to add power and maybe sustain but at the expense of warmth and color.  I've never swapped out necks on the same body to really verify the effect though.  It was just just an educated guess.

I'm convinced that mass and stiffness of the neck have an effect on sound but there are so many variables that I can't imagine the effects are universal.  For instance, it may be that relationships between the box frequency and the neck frequency are the main thing.  Stiffness would be related to that but that doesn't mean that stiffening a neck would have the same effect on tone for all guitars.  As Don said, things work as a system and I think it's often misleading to generalize too much about the parts.

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http://www.chassonguitars.com