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I know Trevor Gore's books are a little new, but has anyone built in this style yet?

I'm sure I'm not the only one who wants to get this dialogue started.

A friend of mine has
His first guitar sounded good(his first ever build), the second amazing.

I plan on starting two falcate builds in a month or two

This has piqued my interest as well. I wonder how suitable the falcate bracing would be for a guitar more geared toward flatpicking. Based on what I've been able to glean from the internet, it sounds like Trevor's SS guitars are primarily fingerstyle instruments.

Jeff - what style of guitar did your friend build?

They were OM sized Guitars

Have you decided what you will use for the brace wood that could be bent.

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hi,

this was my first double top classical with slightly modified falcate bracing...

I use spruce for brace wood

best

My friend just used Sitka and that was fine. Not sure why Trevor is not keen on it.

When I first started building falcates I had a stash of Sitka brace wood that was just impossible to heat bend without snapping it; that really boney stuff. Great for straight braces, hard on chisels, but no good for falcates. Even at 1.5mm it still wouldn't bend how I wanted it to. Hence searching out alternatives. I've recently replenished my brace wood and this new lot heat bends fine. So no reason not to use it. However, the new stuff is no where near as stiff as the old stuff was. But that's wood for you.

Trevor Gore

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

How long has this bracing been around?

That was the question I had in my mind. I seem to recall seeing something similar (as a diagram) in one of the Guitar making books. May have been in the Sloane, Welford or Cumpiano? Certainly '70's or before. Perhaps even long before.

There's nothing resembling falcate bracing in Sloane (Steel String Guitar Construction - Pub. Dutton, 1975) or McLeod and Welford (The Classical Guitar Design and Construction, Pub. Dryad 1971) or Cumpiano and Natelson (Guitar making tradition and technology - Pub. Chronicle 1993) or any other other publication (other than the obvious one) that I've seen. And for those interested in guitar design, I'm afraid there's nothing on offer in McLoed and Welford, despite the title. It's another construction book.

I built my first falcate braced guitar in 2005, though the ideas and initial tests had started long before. The inspiration came from the reinforcing in sails (Google "Tape Drive"). The pics of sails that come up are much more recent incarnations of the concept, which is now very similar to North Sails 3DL technology. The original Tape Drive sails were fairly normal looking "flat panel" sails but with kevlar reinforcing tape stitched along the major stress lines, which are curved load paths across the sail. "Tape Drive" was a trade name, and sails were built under a license from Sobtad (another sail maker). If you can find a pic of this early technology you'll see how the idea was seeded.

Inevitably, this will precipitate a slew of claims pre-dating this, but I don't know of any!

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

I was obviously mistaken with the books. For some reason I have this vague old memory of seeing a type of fan bracing that had been bent. Over the years there has been so many experiments with fan bracing that perhaps it's all muddled my tiny mind!
I'm certainly not suggesting that you are wrong but I've lost count number of times I've heard makers state that things like soundports or laminated Backs are a new concept. Reinvented perhaps but certainly not new.

These posts have had the hairs on my neck standing up.

1. I have intonated my nuts as well as saddles since I started building, because of intonation problems (to my ears any way) on lower frets after years of playing factory guitars - and after reading "The Compensated Nut" http://www.mimf.com/nutcomp/)
2. I have been considering curving my X braces into the UTB for some time now, in an attempt to reduce top deformation over time (if not actually using his Falcate bracing)
3. I sketched out a headstock design just 2 weeks ago for my current SJ build to keep string pull straight, staggering the 3 a side tuners, which was as identical to Mr Gore's as I could have drawn it freehand.

Not sure whether to buy the book or to seek exorcism!

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Lights gone on. None other than Contreras did curved bracing but the curve was in the opposite direction ie. it followed the direction of the lower bouts. I knew I hadn't quite 'lost it' despite all the sawdust! No idea when he first started using bent bracing or if indeed he was the first.

btw i love your books, reading them now.

And...i worked at a sailcloth manufacturer, Challenge Sailcloth for many years. Helped in quality control and testing lab. very interesting stuff. We sold cloth to North and many others. In fact i remember when Tape Drive came out. I worked on the development of the carbon fiber line too. interesting that a guitar building site would cause memories of that...thanks!

b

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brendan 3.0 new and improved, with better interpersonal subroutines

Conceptually, this reminds me of Kasha style bracing. I would be interested in hearing about how it is different.

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Expectation is the source of all misery; comparison the thief of joy.
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I believe that Gary Southwell has been using similar bracing for quite a while.

I haven't had the chance to see Trevor's work, though I'm sure it's well done. Falcate (just a fancy term for curved I think) bracing has been around for quite awhile. I know Steve Klein was doing it in the mid 70's and a few others have followed his lead. I built a number of Kasha/Klein guitars a few years ago with some curved bracing, although mine were laminated maple, not spruce.

I'd be interested in seeing Trevor's bracing scheme and a brief explanation of the theory behind it. Maybe he'll chime in.

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Jimmy Caldwell
http://www.caldwellguitars.com

Michael Cone.

Google "Falcate bracing" for more info and pics. Falcate means "sickle shaped".

A major difference between what I'm doing and Kasha is that falcate bracing is continuous longitudinally under the bridge. Apart from some braces being curved, there's little else by way of similarity.

Gary Southwell has used curved bracing (don't know if he still does), but again, quite different from falcate bracing, with more emphasis on continuous (and curved) transverse braces.

As Michael N. recollected, Contreras used a sort of concentric circular bracing pattern (can't find a pic to jog my memory of exactly how it was configured). Even Hauser used a curved lower transverse brace for a while. Then there's the Sali "squiggle" bracing scheme and the Cone "bent fan" scheme, both, seemingly, fan bracing derivatives and probably many more makers using curved braces in some form or other.

The point to be made is that all sorts of schemes can be made to work (or fail!) and that a great guitar depends on many, many features working properly together, not just one or two.

Trevor Gore.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

According to the drawing in 'Guitar International' March '90 issue, the Contreras !a used
five braces in the lower bout: the middle brace running conventionally straight along
the center seam of the top, the two outer braces on each side of it bowing outward
to follow the curvature of the lower bout, along with a bridge patch which crossed the middle
three braces.

What similarities are seen between 'Falcate bracing' and Kasha bracing in its
various forms?

Just to be devil's advocate here - the leap from sail to guitar top seems kind of broad to me? Although it's been years since I've done any real engineering, I just don't see the similarities in loading between a guitar top and a sail.

As I understand it, tape drive is to keep sails from deforming from their optimal aerodynamic shape - the tape drive is always in tension. Apparently sails without tape drive will stretch eventually to the point where they perform poorly compared to a new sail that still holds its shape properly.

Can you elaborate a bit? From my end, I just can't make the connection.

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It's the abstraction of the concept and it's re-application that provides the link.

The abstraction is "put the material where the stress is and then "dump" the stress over a wide area".

All this is very obvious to any engineer; it's just that every now and again you need something to remind you of the principle; making sure you're seeing the wood and the trees. The major loading and stresses on a guitar top are around the bridge. Hence the concentration of the bracing under the bridge in the falcate system and the flaring of the braces to "dump" (dissipate) the load over the rest of the soundboard. The original "tape drive" curves precipitated the curved brace idea as an efficient way to spread the loading.

Here's another example of how my brain seems to work: Years ago I saw a car advert which proclaimed that the car company's engineers had made the chassis stiffer, in order to improve handling. I can't remember the brand of car! But the idea that stuck was that they measured stiffness in Hertz (torsional vibration frequency of the chassis). Not the unit for stiffness that I would have expected, but very sensible when they were looking for extra stiffness for a given mass of material in the chassis. All very obvious again, but it was that advert that made me think that that is exactly how I should think about guitar tops; look at the vibrational mode frequencies (and the rest, as they say, is history).

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

That's kind of a bold statement I'd say. Out of curiosity, do you have a degree in engineering?

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http://banduramaker.blogspot.com