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I am currently building 2 guitars side by side. One is a black limba back and sides, the other is cocobolo. Identical measurements in almost every way. I'm working out a new design and am changing very minor things to try and get the best product I can.
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The difference in weight between the two of these is almost a full pound. 15 ounces actually. Is there any way to lighten up the cocobolo or am I just stuck making a heavier guitar if I want coco? The back is down to 2.5mm and the bracing is pretty light.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

I'd say you could take cocobolo a good deal thinner than black limba, based on strength and density, but that's probably about it. Or you could put 10 more of those neat soundports in it!

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Depending on how well quartered/stiff the back is, and if the guitar is smallish, you could easily take it down to .075". It really depends on the individual piece. If it's flat-sawn on the edges and not quite stiff you're stuck with the weight. What size guitar is it and how thick are the sides?

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

I don't have any data to support this hunch that I have but I suspect that you can narrow the gap between the weight of the two guitar by finishing the coco one with the FP technique (stated as a technique for my buddy Rod so he does not have to dent his head any more).

Sand back the pore filler to bare wood, FP, and my guess is that you will save several ounces over a nitro finish with a thin layer of epoxy finishing resin left on the guitar as a pore filler and sealer. But again I don't know this for sure - it's just a hunch. And you don't have to undo anything that you have already done to realize the benefit.

Heavier wood tends to weigh more, in my experience.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

You can't fool me Howard!

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I've found the reverse to be true as well; woods that weigh more are heavier.

Sorry, j. That's not very helpful, is it?

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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

Leave the truss rod out and use flamenco pegs for tuners.....

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It's not the miles ahead, it's the stone in your shoe


In Markham,Virginia

I suspect that taking the wood to a planet with a smaller gravitational pull would do the trick.

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

Going to another planet would be ideal, but possibly cost prohibitive. You might try stuffing the inside of the guitar with helium balloons, but that "could" muffle the sound somewhat. (Hey, Howard started it...)

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Eagles may soar, but weasels don't get sucked into jet engines.

Why is overall weight your priority?

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Instagram: @jfrenchluthier
Web: https://www.jfrenchguitars.com/

A quick huff of the contents will help with hitting those high notes, though!

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

While we're all in the mood...if you can't make the coco one lighter, then you'll just have to make the other one heavier, that will even things up!

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

I guess that should read... "Should I lighten up a cocobolo guitar?"
Its not necessarily a priority, I'm just surprised that its a full pound heavier. I guess I'm wondering if that is typical or do others out there take this into account and start shaving some weight by thinning, etc.? I think Hesh has been working on lighter builds, but what about everyone else? When is weight a concern for any of you, if at all?

I'm thinking I can probably inject some air into the body through the soundport. That should help a lot.
-j.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

In keeping with the vein of this thread.... Did you know that hot air is lighter than cool air? There is plenty of hot air around here!

Especially mine!

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Steve Walden
Aspiring Builder,
Bartlesville, OK

How do the weights of the tops compare, j?

Seems to me that you'll get more efficient movement as a result of lighter bracing and stiffer and lighter tops. Given that you've spent your attention there, I'll bet they both will sound great.

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JJ
Napa, CA
http://www.DonohueGuitars.com

Just like JJ to get us back on topic! Thanks JJ!

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Steve Walden
Aspiring Builder,
Bartlesville, OK

Cocobolo, like Honduran RW, bloodwood, pau rosa etc., is quite heavy. Much heavier than Braz, or Indian RW. So everything else being equal a cocobolo guitar will be heavier…

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

They're within about an 1/8 oz. of each other, but thats rough cut weights that may not be exactly the same.
I just closed 'em up and they sound pretty good tapping on them, so I hope they stay that way and keep getting better. They pass the match test anyway. Not that it says much about the guitar, but its cool to see it.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

Let's see: thinning the back from .098" (2.5mm) to .075" lets us eliminate 23.5% of the weight from the back. Given that cocobolo is much heavier than any spruce, I suspect the saving in weight is much more than 6%. For the body alone I would assume around 15%.
If weight is what we're after, of course…

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

A classical guitar is about 1200cm2, lets say 1400 for an OM ?
I hope my math is not completely wrong:
Then a layer of 0.6 mm (from 2.5 to 1.9mm total thickness) will be 1400x0.06=84 cm3. That would be 70 to 80 grams of Indian rosewood depending on density. 80 to 90 grams of Coco, and make it 150 grams if the sides are thinned a little too.
Not sure how much 150 grams count for a SS, but i would happily shave off 1500 off a classical.

You can also save weight by using Spanish cedar reinforced with graphite for the neck instead of mahogany.

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Build log

I've just spent the morning sorting through my Brazilian, cocobolo, Cambodian, and Indian rosewood piles, and I'm amazed at how much heavier the cocobolo is than anything else. This is some amazingly dense stuff, and it sure is beautiful.

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