Official Luthiers Forum!

wow unsuitable! Two of my best have been Curly Redwood and Curly Koa but I know best is subjective.

Yes curly wood has lots of run out. Depending on all thing it is true that Curly is handicap to start with but to say it is unsuitable is like saying challenges can't be over come.

I thickness-ed both of the Redwood top I have built with to .130 to start and thinned at the perimeter during voicing to .115 or there about.

Does bear claw have the same increased risk of shatter?

Let' see how really curly tops hold up over time.   

Oh, we don't have to. All we have to do is look at curly topped ukes.   They don't hold up well...

This is an example of how important it is to study older instruments.   Most luthiers here do not have a lot of experience as repair techs. You learn a lot of what works and what doesn't working on vintage instruments...

The emphasis on "zoot" here to the detriment of longevity and utility may come back to haunt a lot of luthiers. It's amazing how conservative you get on certain issues after about twenty or more years of doing repair work...

[QUOTE=Bill Bergman]Does bear claw have the same increased risk of shatter?[/QUOTE]

Good question Bill - thanks for asking it.  I was thinking the same thing and have a bear (Serge) claw top two weeks out of the oven that I hope to join this week.

[QUOTE=Rick Turner]
Double tops are not the answer.   The strength of a double top or any "stressed skin panel" depends almost entirely on the skins.   Thinking that you can get away with really thin incredibly weak wood for the outer skin shows a lack of understanding of how double tops really work. [/QUOTE]

I disagree with that statement. I did many studies with double tops, specially the nomex method and after a few tests I came up with an wood double top that does not use nomex. Nomex didn't seem to have any tonal properties and has poor glueing surface. This is my own design and will be featured as a standard feature on my Zion guitar. In fact my double top addresses all areas of runout and would problably survive even if the top layer was only half the thickness.

_________________
Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

Back to engineering school, folks.   If anything, the structural integrity of the skins is more important in a honeycomb sandwich construction than in a solid top.   It's not "about" the core, and it has nothing to do with the gluing properties.   There's a very good reason why hight tech honeycomb panels are made with continuous CF fibers...there's no "grain runout".

I think we must work extra hard not to fool ourselves when we listen with our eyes. Just because you want your most outrageous looking guitars to sound good doesn't mean they do. It also doesn't address the issue of longevity.

Curly redwood to me is a ticket to future warranty work.

[QUOTE=Rick Turner] Back to engineering school, folks.   If anything, the structural integrity of the skins is more important in a honeycomb sandwich construction than in a solid top.   It's not "about" the core, and it has nothing to do with the gluing properties.   There's a very good reason why hight tech honeycomb panels are made with continuous CF fibers...there's no "grain runout".

I think we must work extra hard not to fool ourselves when we listen with our eyes. Just because you want your most outrageous looking guitars to sound good doesn't mean they do. It also doesn't address the issue of longevity.

Curly redwood to me is a ticket to future warranty work.[/QUOTE]

Everyone is entitled to their own opinion.....How many double top redwood guitars have you seen that had the tops failed?

_________________
Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

[QUOTE=Rick Turner] Let' see how really curly tops hold up over time.   

Oh, we don't have to. All we have to do is look at curly topped ukes.   They
don't hold up well...

Ya but have seen the way some of those uke players abused their
instruments. Tiny Tim? The guy was a maniac! The big Hawaiian dude who
did the great job on Over The Rainbow? He could crush any axe . Build
what you like and accept the results.
Cheers,
Danny

On the engineering front, Rick's correct, again.

the "core" is only there to separate the skins, making them "act" as a thicker unit. Same principle that makes a I beam work, makes a truss work, etc...

Build
what you like and accept the results.

And there's the reason every city/county/state/province has building codes. How would you like it if the mall's roof caved-in on your wife and kids?? And the contractor responsible just shrugged ad said, "well, it -was- a pretty roofline. Oh well... Sorry 'bout the family". And when your client takes your instrument out on Christmas Eve and it folds up like a $5 lawnchair while he's tuning up to play "Silent Night", y'all think Cousin Elmo will call you up next week to place an order? Even if it's your own person instrument, if it folds on you while other are present, it won't bode well...

There's a line to be drawn, and a balance to be struck, for sure. And we all take risks(or we'd all be building with plywood), but don't just state Build
what you like and accept the results.
".

I hope never to see a double flamed redwood topped instrument fail, and I know I'll never see one built by me fail because I absolutely hate warranty work. I can't imagine a less appropriate skin for a honeycomb panel than ultra curly wood.

Once again I have to say that too many of you here have too little experience in the front lines of guitar repair work. You have no idea what happens to guitars over even ten years much less fifty years or one hundred years or more.    I see a lot of luthier-built and even some boutique manufacturer-made guitars that are taken so close to the edge that they are explosions and implosions just waiting to happen.   Yeah, you get that big opened up sound very quickly, and then in five or ten years...whoa! neck reset time...or the sound becomes all whump, whump, and the guitar is quietly retired to being a beautiful wall hanger.

Rick,
with all due respect,
I do appreciate your input and experience, however as you mentioned you can not speak from experience on double topped curly redwoods.
While I think you may have reservations as myself and many others do regarding those soundboards, it would be nice for you to express your concerns in a "help out" way rather than a criticizing way. In one of your previous posts you expressed how you really didn't like the way you where judged by one of the teachers at a class you attended and by the way "he" judged your instruments without even ever had seen one.
I do now know how you felt because thats the way some of your posts make me feel.... mostly critique and ridicule of some people that are just trying out now to build some of their first instruments. Sometimes you have to fall in order to learn but there's no need to have someone push you down.
I was somewhat discouraged when I posted my desires to try a new version of a double top, now some of those same people have emailed me so I could explain how I do them.

Its nice to learn from one's own mistakes and other people's experience but not much can be learn from discouragement.

_________________
Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

Peter, what I see here is the desire for a beautiful wood to be perfect for the outer skin on an engineered stressed skin panel.   It's not. The only way you're going to get it to work is to make it thicker than would be ideal for tone. I think you're letting your desire for beauty to overpower the basic need for a top to be structurally sound. You are trying to will this into being right, and I just cannot believe, knowing what I do about curly redwood (don't forget, I live where it grows...) that it is anything but a visual aesthetic choice on your part or anyone else's. You would not choose this stuff for tone or structural integrity, and saying that you're using it in a double top and thinking that that erases all the negatives for using curly wood is just plain bad engineering. This simply goes against everything we know about what makes for a good guitar top.   

But if you want to sell bling and if people think it's great, fine.   Just don't be surprised when you have to do a re-top.   

This is guitar making as a visual art, not smart lutherie, in my opinion. If people want to listen with their eyes, fine... As far as I'm concerned, you might as well make the top out of plywood...it would be stronger.

Rick is right...the majority of what we learn in lutherie comes from empirical knowledge.  We must learn from what has been successful in the past and why that knowledge has proven over time to be the right direction.  If we fail to learn from the past then all of these "breakthroughs" that are not based on solid engineering will eventually fail and be relegated to fads that came and went.

Recently there was a thread about the merits of a classical guitar with a Tornavoz and there was not enough evedince as to the benefits or how to evaluate them to make a critical determination as to its merits.

Too little is known about alot of things in the lutherie world...the tonal longevity of Western Red Cedar for tops, whether Dr Kasha was on the right track, whether 50 years from now Smallman will be seen as genius or a passing experiment...as much as we know or think we know about guitars we need to continue study from the past and apply it to our designs to move forward.

Two of the most successful builders of Acoustic Electric guitars are Ken Parker and Rick Turner.  If they had been just Electric guitar builders they could not have made the advances in designs they have.  Their knowledge of acoustic guitars and years of experience in guitar repair of both good and lousy instruments is part of the experience that they applied to how to build an acoustic electric, how to electrify one and how to refine the instrument in a way that performs well and sounds good. 

Too much of our lutherie discussion is about imprecise descriptions of tone and how a guitar sounds.  In order to improve and to advance our art and craft we need more voices like Alan Carruth, Rick Turner and others who often shock or upset people into facing the real issues... build on empirical information using well known examples from great builders and learn from how each build works or does not work.

Life is too short for hurt feelings and misunderstandings... once we have built as many guitars , basses, ukes, or whatever as Alan Carruth, Rick Turner, Erwin Somogyi, Kevin Gallagher and others that have been part of OLF, then we can speak with as mush authority as they do.

Regardless of where you fall along the spectrum of bling to no bling,  it has to sound good and be built well to stand the test of time.

 

This is not about whether I'm right or not; it's about whether curly redwood is an appropriate top wood.

If it were not for the looks, this wood would not be considered.   It simply does not have the right combination of stiffness to weight AND tensile strength to be in consideration as even a third rate top wood. As far as I can tell, the ONLY reason why it's being considered as a top wood is because of the bling factor. I haven't yet read one word about tap tone...

A guitar made with this stuff will sell, no doubt, but I'll bet that it sells to an unsophisticated collector who listens with his or her eyes, not ears.

Just do what Ervin does sometimes with spruce tops that he chooses not to put on guitars...take it and make an art piece out of it.   Incise nice carvings into it; do some guitar-style inlays; and frame it.   Ervin's spruce art work is beautiful; the same would be nice in curly redwood.

I have been taken in with the bling of curly redwood. I started to build one about a year ago but the top fell apart in my hands. I still want to build with it, but it will likely be a plywood top - redwood on lutz. I don't think that a double-top with nomex is a good idea with curly redwood.
I'll probably build myself a plywood top guitar to see if I like it. There is a bonding technique that applies dots of adhesive in a grid - say every 1/8 inch - that I've been thinking about. It should hold the top together without increasing the weight too much.

_________________
"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

[QUOTE=Shawn]

Rick is right...the majority of what we learn in lutherie comes from empirical knowledge. We must learn from what has been successful in the past and why that knowledge has proven over time to be the right direction. If we fail to learn from the past then all of these "breakthroughs" that are not based on solid engineering will eventually fail and be relegated to fads that came and went.

[/QUOTE]

Sure, but neither is lutherie exempt from the laws of physics. We know some things because they follow from those laws.


[QUOTE]Too little is known about alot of things in the lutherie world...the tonal longevity of Western Red Cedar for tops, whether Dr Kasha was on the right track, whether 50 years from now Smallman will be seen as genius or a passing experiment...as much as we know or think we know about guitars we need to continue study from the past and apply it to our designs to move forward.

[/QUOTE]

Well, we do know about whether Kasha was on the right track. Besides the empirical results, there is overwhelming evidence from laser holography showing that guitar tops do not vibrate as he conjectured. His ideas about impedance matching were misguided, too.

[QUOTE] ... once we have built as many guitars , basses, ukes, or whatever as Alan Carruth, Rick Turner, Erwin Somogyi, Kevin Gallagher and others that have been part of OLF, then we can speak with as mush authority as they do.

[/QUOTE]

I like the idea that Rick speaks with mush as his authority. But the idea that one must have built some particular big number instruments in order to know what he is talking about is false. It is the rhetorical device of someone who cannot offer good reasons to say, "I've built X number of guitars and you haven't, so I'm right."

_________________
Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Practically everything we know about stiffness to weight comes down to long, long fibers that resist stretching being at the surface of a structure.   The reasons why spruce, cedar, and straight grained redwood are good for tops is that they have this fibrous structure in a relatively lightweight matrix, and they have a damping factor that is right for how we perceive tone.   

I think it's important to understand the "why" behind centuries of empirical knowledge that has led to certain wood choices being appropriate for different parts of a guitar.   These choices are not accidents.    

I do see a lot of young luthiers want to go all different and freaky with choices without having the slightest understanding of the engineering rationale behind the traditional wood choices.   It's all bling and zoot and there's little or no understanding of the inherent qualities that make for good tone wood.   Just because Strad or de Torres or C.F.Martin didn't have engineering degrees does not mean that they did not understand the qualities required for tone and structure.

Curly woods are beautiful...and they are unstable as can be, they are weak, and they are nothing but grain runout...one of the factors so many try desperately to avoid when choosing tops.   Incorporating curly woods in honeycomb layups only exaggerates their weaknesses by exposing all the more end grain to the surface compared to the length of the fibers. In cross section, the top layer of a double top is going to look like this:

///\\\///\\\///\\\///\\\///\\\///\\\


And the thinner you make that top layer, the worse it gets.

I've used wild grained wood for the tops of electrics...laminated to a substrate, and I've used it for tops on my Renaissance acoustic-electrics...with a center block and saturated with epoxy. I agree the stuff is drop dead beautiful...and you'll never see me use it for a real acoustic top.

Bear claw is different to an extent...the claw figures seem to be extra dense and perhaps that sets up a whole other set of nodes and antinodes in vibration patterns.   It's going to have a more complex set of Chladni patterns, for better or worse. I have not noticed any particular weakness with bearclaw spruce.

[QUOTE=Rick Turner]


Bear claw is different to an extent...the claw figures seem to be extra dense and perhaps that sets up a whole other set of nodes and antinodes in vibration patterns.   It's going to have a more complex set of Chladni patterns, for better or worse. I have not noticed any particular weakness with bearclaw spruce.[/QUOTE]

Thanks Rick - I was just about to ask this question again since I have a bear claw top two weeks out of the oven and ready to join.

I have been doing some experimentation with nomex sandwiches recently, some with curly redwood.

There are a lot of minuses but certainly some positives as well depending on the tone an end user might be looking for. I'm not ready to write it off just yet. I will certainly share my results when my experiments are complete.

No reason to write this stuff off. It's bound to make beautiful drop tops for
electrics!

    This is an interesting thread and has, as usual presented lots of great
information from lots of great builders.

   I do agree that sheer numbers of instruments built are not a foundation
for credibility to be ascribed to any builder, but numbers are important if
the builder has been paying close attention to each of those instruments
that he's built and understands the subtle differences in them brought
about by even the smallest design and material changes from one to the
next.

   "Repetition is the mother of all knowledge", is a powerful cliche that
really holds alot of truth, but the truth in it only becomes real when the
person repeating anything in an effort to grow or learn is paying attention
and learning from each cycle in that repetitive loop.

    If you build guitars for the sake of accumulating numbers and not
improving and learning with each one, all that you'll accumulate is
numbers. If you are building guitars with a keen focus on the pursuit of a
better guitar with each build, you may take longer to amass those
numbers for boasting rights, but you will gain a great education and pure
knowledge that can not only benefit you as you build, but others as they
seek advice and encouragement from you.

   There is a well known builder who has built for some very high visibility
players and is famous in certain circles who has obviously just built for
numbers' sake in many ways. He has had lots of press and exposure and
is still building what i would consider entry level guitars inspite of the fact
that he claims an extremely deep backlog and hundreds of guitar to his
credit. I've played a few of his more recent guitars and was surprized at
the lack of attention to details that custom guitar buyers have come to
expect from experienced luthiers. The tone is what has surprized me
most, though as the guitars have been muted sounding and sort of
clunky or subdued.

    Being secure in your knwoledge will find you openly sharing your
experience and findings with anyone who asks and not huddling over it to
protect it like you're eating in prison. Sharing out of a desire to help
people to grow while saving them some of the troubles and headaches
that the more experienced luthiers have suffered isn't a bad thing and is
both generous and commendable. At the same time, any level of
contempt for a more experienced luthier who has proven his salt worth
through years...or decades of hard work and long research efforts is not
necessary or justifiable.

    That kind of open sharing has become the foundation for the nature of
this forum and it is more present and evident here than at any other
forum on the web, in my opinion.

    If you're having great success with curly Redwood tops, whether single
of double layered, use them and be ready to deal with any problems that
may appear in the future. If no problems ever come up with them, you've
proven the validity of your choice to use them. I've built with them and
have had no problem with any of the almost two dozen that i've used, but
i've heard horror stories of guitars self destructing as the runout in them
surrendered to string tension and bridges pulled off, tearing the top apart
as they did.

   I may have just gotten "lucky" with my placement of the tops and
bridges in relation to one another or the fact that I always try to place the
bridge on them in an orientation that will present the least potential for
failure....I don't know, but I tend to think that both may have played a
part in their success. The oldest in almost 15 years old now and is still in
great shape...and its owner uses very heavy strings and has since the day
I set it up to ship to him.

   Numbers are nothing to be dismissed since there are a few guys who
have built very few guitars and have declared themselves t be authorities
on guitars and guitar building (mostly through intmidation and bullying
tactics). On the other hand, there are some who have built hundreds of
guitars while closely observing and documenting even the smallest
details...no matter how insignificant thay may seem to others...who are
still willing to listen and learn from the experiences of much less
experienced builders.

    If a poor approach comes up, though, these more experienced builder
should, out of consideration offer advice from their own experience on
the potential for failure or future work and expense that can come as a
result. I believe that's the spirit that Rick has offered his input here
with...not to discourage or to demean anyone else or their techniques. We
all have to prove our own methods in our own shops and then use those
that are market worthy.

   "To each his own", seems so lazy to offer here and I apologize for using
it, but that's where it all really falls. If it works for you and makes your
customers happy for decades to come, by all means, use it.

Regards,
Kevin Gallagher/Omega Guitars

One of the things I tried to do was to make obvious the paradox of on the one hand worrying about things like grain runout, and on the other hand choosing a top primarily for it's visual appeal.   Curl is runout, plain and simple.

I have yet to hear of anyone touting curly redwood as the next Adirondack.   Maybe Adirondcrack...   And I have yet to hear a curly topped instrument that beats the sound of a straight grained, well chosen top of the same wood. So if you want to build for beauty first, what the heck...go for it...and be prepared to do some repair work someday.   The curly redwood topped instruments that I've seen go bad were pretty ugly messes...

Rick,

   The ones i've seen come apart were disasters, too. They sure are great
looking tops, but tonally, they've never done much for me and leave me
feeling like they need alot of coaxing to a place where they present grea
tone a response. I'm not a huge Bear claw fan either, but will use it at the
insistence of a customer.

   I build any guitar that will stay with me for tone first and the level of
inlay and adornment usually surprises people when they see the
"luthier's" personal guitars. The funny thing is that, once they hear the
guitars that I've built for myself, they will abandon their heavily inlaid and
adorned intentions and buy them on the spot.

    It's happened every time I've had a guitar in my posession. I may have
built it for my own use, but mostly t have a demo piece on hand to
represent my work and tone, but they're always for sale (what isn't?). The
lure of no wait and the tone is great enough to keep them moviong out
the door. Those customers who buy them usually call back to say that
they've really grown attached to the more understated and plain
appearance of these guitars.

   My son just built his first guitar as a graduation project for high school
and he copped one of my very best straight grained Redwood tops and a
beautiful set of Cuban Mahogany that I'd been saving for my personal
use. We'll be stringing it up and playing it for the first time tonight and it
gives every indication of a killer sounding guitar.

    Dark Rosewood bindings throughout and purfling only around the top
edge capped of with Rosewood rosette and head veneers, no inlay in the
fingerboard and all those warm browns and oranges blend together to
present a ver organic appearance. He leans toward the understated, but
looks forward to learning the art of inlay and the skill of mitering
purflings and applying Abalone everywhere possible to be able to offer
them to his own customers one day.

   Appearance is wonderful but tone is what puts the "ummph!" behind
any guitar.

   I'll have to remember that "Adironcrack" term for future use, too.

Regards,
Kevin Gallagher/Omega Guitars

I think there is merit in trying new things, even if the apparent numbers aren't there to support a successful venture. If Kasha hadn't tried it, we wouldn't know today if it worked or not. We wouldn't have electricity, or phonograph records. The integrated circuit might never have been invented, and as a result, we wouldn't be sitting at our computers typing away and discussing this. All that stuff happened through innovation, and a person willing to try something new to see if they could make it work. Good ideas happen, and often if people persist, they find a way where others haven't.

Some manufacturers have used laminated tops for decades now, and some with decent success. Who is to say that Peter hasn't come up with an idea that may work beyond what we have currently percieved of as possible? Sure, intense curl on a redwood top is 100% runout...but maybe he's using that as a top layer of what is essentially a 2-ply top, and perhaps he's anchoring the bridge down through the bridge plate somehow to take the stress off the glue joint between the bridge and the redwood. There are other posibilities...

Folks, until innovation is given a chance to happen, no progress will ever be made. We'll just fall back on experiences of the past and stay in the same rut that we're in, be it good or bad.

I saw a guitar produced by Sergei DeJonge at the last Newport show, which had crazy quilt bubinga for a top, and I asked them about it. Turns out it was a sandwiched top, and it sounded fantastic. Just because there have been past issues doesn't mean someone won't come up with a solution to a problem where none was before.

A friend of mine works for a company that makes pressure vessels in a way that nobody else ever tried, and they can take it to limits nobody thought was possible either, and yet there they are doing it when nobody else is, because someone had an idea...

I appreciate the words of wisdom spoken through years of experience, but it only takes one innovator who stumbles on a new way to blow all that old stuff out of the water.

Instead of saying "It can't be done because..." how about saying "It's never been done before, but who knows?"

Helicopters aren't supposed to be able to fly either...

_________________
"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."

Just don't let your eyes do your listening for you, and if you're going to innovate, build possible warranty work into your prices.

I have to come back to the concept that there are actual physically measurable reasons why the woods and grain orientations that are "traditional" have become so. It's not just tradition based on "old wives tales", etc. Stiffness to weight, density, fiber length, damping and it's corollary "resonance", impact strength...these are all factors that go into a recipe for what woods or other materials are appropriate for different parts of a guitar.

For instance...the very worst bass neck I ever saw was gorgeous flame maple.   Zoot up the ying-yang.   Curl to die for...and the worst backbow I've ever seen and a neck that could have been used as a long pointer on a humidity indicator.   That peghead would move a full 1/2" on a 20% humidity change.   Wall hanger.   Future land fill...

I'm all for trying things; I'm all about innovation; but I don't let my desire for positive results cloud my objectivity.