Official Luthiers Forum!

Thanks Carey

I'll check my old issues. I just might have it.

_________________
Joe Beaver
Maker of Sawdust

I worked on three Milleniums dating from 2007-2008. Two were from Mr. Humphrey’s last batch: of those, one was completed by Mr. Humphrey before he passed away and the other was completed by an associate. All three had the bracing pattern in the sketch. The X’s were tapered spruce braces capped by carbon fiber and were very slight compared to what would be used on a steel string guitar. The lattice members were spruce of typical size. The soundboards were spruce, uniformly thicknessed to about 1.6 mm.

The main X isn't coupled with the lattice parts?

_________________
Francis Richer, Montréal
Les Guitares F&M Guitars

No, as I remember the latice ends are not tucked into the X.

David LaPlante wrote:
"Yes Martin did make 000 12 fret guitars for gut starting in 1902 and nylon up through the mid 1960s. They weren't very good though compared to the smaller sizes and even Martin switched to the smaller 00 size for the style 28C guitar in 1966."

Yes, it's far easier to make a good small gut/nylon string guitar than a large one. In Martin's case, as a production shop, they could not possibly take the time to pay attention to the details, such as using the lightest possible wood for the top, that will make the difference in a large bodied classical. That does not mean it's not possible for an individual luthier to do it. Sharon Isbin was quite impressed with my 'Autumn' guitar when I showed it to her: if it were not that it has a cedar top, and she had just gotten her first cedar-topped Humphrey, I mught have gotrten someplacwe with it. As it was, she talked herself out of a longer trial of it.

One thing I will add is that X bracing is structurally more efficient than the usual fan bracing. Properly done it allows you to keep the weight of a large top down somewhat. My largest fan braced classicals are a bit smaller than the 00 size, although they're larger than a 00, which is about a 'normal' modern classical size. I would not use X bracing on a standard size classical by choice.

Gary,

Thanks so much for the sketch. It looks a lot more like what I thought an x-braced/lower bout lattice bracing scheme should look like.

You say the the main x uses slight wood capped with carbon fiber. If I was to use something like 1/4x1/4 spruce tapered to 0 and capped with 1/32 carbon fiber would I be in the ballpark? Or maybe making a sandwich of 2-1/8"x1/4" spruce pieces with the 1/32 carbon fiber in the middle? Again tapering to 0?

I know it is just a sketch but it looks like the outline has a larger than normal lower bout. You wouldn't happen to have the body dimensions would you? I know I'm asking for alot and I thank you for what you have already done.

_________________
Joe Beaver
Maker of Sawdust

Alan,

I'm a big fan of Sharon Isbin and to have her consider your guitar so carefully says alot about your classicals. Sounds like timing was the issue here. I'm encouraged to proceed with an x-braced.

_________________
Joe Beaver
Maker of Sawdust

I think that 1/4 X 1/4 braces toped with 1/32 of carbon would be way too much. It's not uncommon to see 4mm-5mm fans on a classical.
Here's what I've been doing, ala Greg Byers.

_________________
Jim Watts
http://jameswattsguitars.com

Jim
Nice looking top.

The lattice/fan braces look like maybe 1/4" x 1/8" for the under fans and maybe 1/4" x about 5/16 tall for the over fans?

_________________
Joe Beaver
Maker of Sawdust

Joe, the over fans are 3/16 tall and the underfans are .07 tall. It's really very light.

_________________
Jim Watts
http://jameswattsguitars.com

Alan wrote:
"Yes, it's far easier to make a good small gut/nylon string guitar than a large one. In Martin's case, as a production shop, they could not possibly take the time to pay attention to the details, such as using the lightest possible wood for the top, that will make the difference in a large bodied classical. That does not mean it's not possible for an individual luthier to do it"

Indeed, I have a Hernandez Y Aguado guitar which is large by most standards and which is superlative. The top is around 2mm overall and the back and sides are rather thin (2mm or less) as well.
However, the wood used is extraordinary. Far better than what we can source today without great expense even if it could be found.
BTW,
All these lattice tops look way overbuilt to me .....are we talking balsa instead of spruce braces here?
Or pehaps a really thin top?

David, I believe the tops end up in the 1.6-1.8 range for spruce, depending on density. Also Byers' tall braces are much narrower than Jim's picture, so I don't know. Is that an even thinner top?

_________________
Build log

Very interesting stuff

Here are a couple shots of Gregory Byer tops I borrowed from his website

_________________
Joe Beaver
Maker of Sawdust

I defer to Greg's expertise, but it still looks like a lot of structure to my eye.

_________________
Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

But the top can be as thin as 1.6mm even in the center and that is on a large guitar not a tiny Torres... The free plate probably weights less than 100 grams while a normal top can be as much as 135 grams. The underlying fan is made about 4.5x2mm which adds up to less than 10 grams, while the tall fan is not heavier than whatever we use in a Torres or whatever. All in all it is a lighter structure than in a traditional top, and being well spread out helps it work on a large plantilla.

_________________
Build log

Lattice bracing looks like a lot of wood to me also. But.... I guess when they are done right they can be great!!!

_________________
Joe Beaver
Maker of Sawdust

Joe,
I'm sorry, I didn't make measurements on the Mils' bracing or plantilla since the Mil sound is not my cup of tea.

10-4 Gary, thanks anyway.

_________________
Joe Beaver
Maker of Sawdust