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Ukecaster
05-04-2018, 02:41 AM
I see high end or custom instruments with sandwiched necks, typically with layers of light colored maple up the back, and on the headstock. Looks cool, no doubt, but Is this type of construction purely decorative, or does it serve a structural purpose too, perhaps in lieu of a truss rod? Thanks.

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bsfloyd
05-04-2018, 03:07 AM
Laminated necks when done correctly are definitely stronger. (and they look nice too :))

greenscoe
05-04-2018, 03:18 AM
Laminated necks are stronger and more stable, so there's little chance of getting a twisted neck. And I agree they look nice too if a contrasting centre wood is used.

As a maker, more care is needed to keep things symmetrical if using a contrasting wood. If the central element is off centre, it's particularly noticeable at the heel. The headstock can be veneered and cover any error there.

printer2
05-04-2018, 03:27 AM
I am not that convinced they are all that much stronger. Mind you a laminated neck does help out if you hit the neck on something and with a solid piece of wood it cracks along the grain line. If you use a harder wood in the middle and there was an appreciable amount of center wood then yes. Doing a bookmatch type of sandwich of the outer wood does help by canceling out some of the movement that humidity changes may cause. Most of the time this is not an issue on a good piece of wood for necks. The center strip can help with the visual aspect rather than joining the side pieces without it.

13down
05-04-2018, 03:50 AM
That is a very good question. The two brands that I've played who have sandwiched necks are Bruko and Loprinzi. I know that the ukes are good and I know they have a good reputation for being durable, too. So I'm going to say "At the very least, they don't hurt." I've been assuming that they help with structural integrity, though you do have a point in that I'm not positive they actually do have a structural purpose.

Diogenes Blue
05-08-2018, 08:49 AM
Laminated necks are absolutely stronger and less susceptible to twisting / warping. I find them aesthetically pleasing.

printer2
05-09-2018, 05:06 AM
Laminated necks are absolutely stronger and less susceptible to twisting / warping. I find them aesthetically pleasing.

Less susceptible to twisting and warping maybe, but how does the strength increase? Unless you stick in a stronger wood then a laminated piece should be no stronger than a solid piece.

Diogenes Blue
05-09-2018, 06:12 AM
It's in the way the grain in each layer opposes the other. It makes a stronger neck.

printer2
05-09-2018, 06:22 AM
It's in the way the grain in each layer opposes the other. It makes a stronger neck.

That mean nothing, sorry to pick on you, I just hear this all the time and nobody explains how it makes the wood stronger. Either way, solid piece or a laminate of the same wood, the outer fibers of the beam (the neck being a beam) takes most of the stress. I don't see the outer fibers being any stronger, the main concern is the wood being pulled apart as it is being bent. The inner fibers are in compression (the inside of the bent neck) and they do not fail before the fibers in tension. Unless the wood has the grain at an angle to the length of the neck a solid piece should be in the same range of a laminated piece.

Rowka
05-09-2018, 08:55 AM
People are using the word "stronger' when they mean stiffer, which is not the same thing.

Diogenes Blue
05-09-2018, 12:55 PM
There are many studies similar to this one on the interwebs. What I never see are studies showing the opposite to be true.

ABSTRACT:

"The neck of guitar is a mechanical structure with a complex geometry which involves many operations and technological solutions with minimal materials consumption, and providing rigitdity to maintain the strings tension during the playing. meeting these requirements is an ongoing challenge for manufacturing because the wood used in the structure of the guitar neck is different as a speicies, as a structure, as physical-mechanical properties and rheological behavior. The paper containing mahogany-maple-mahogany and others containing masarnduba-maple-masaranduba. The samples were subjected to the three-point bending with different intensities of loads (400, 800, 1000, 1400 N), determining for each maximum deflection and the maximum stresses. It was found that the use of laminated wood increases the rigidity of the guitar neck and the bending resistance; the most advantageous combination is masaranduba-maple-masaranduba."

"Keywords: solid wood, glued laminated wood, guitar, three points bending, stifness, beam of constant strength"

RESULTS AND DISCUSSION

"Analyzing the values of maximum displacement in the force direction, it was found that samples from solid wood presents the greatest deflections, regardless of the applied load , which is about 120..250% higher than values obtained on laminated wood samples made from m asaranduba with maple (Fig. 4 a, b). This indicates that guitar neck stiffness can be increased by using a combination of least two wood species"

http://aspeckt.unitbv.ro/jspui/bitstream/123456789/2144/1/272-277%20Paper%20comat%202016%20Stanciu%20%28Engl%29. pdf

Ukecaster
05-09-2018, 01:05 PM
After all that, I need a sandwich, thanks! ;)

BuzzBD
05-09-2018, 01:06 PM
For my arch top guitars and ukulele, I sandwich a v shaped piece of mahogany between two pieces of maple, cut at 45 degrees. When shaped the neck looks like a piece of bookmatched maple with a thin mahogany stripe down the back. It is in fact about 70% mahogany, which is far more stable than maple.

Ukecaster
05-09-2018, 01:12 PM
Another angle on this...just got on a LoPrinzi tenor, with a sandwiched (laminate) neck. The depth of the neck is thinner than most, so I assume the laminate neck provides additional strength, although I see some LoPrinzis without it.

printer2
05-09-2018, 04:25 PM
There are many studies similar to this one on the interwebs. What I never see are studies showing the opposite to be true.

ABSTRACT:

"The neck of guitar is a mechanical structure with a complex geometry which involves many operations and technological solutions with minimal materials consumption, and providing rigitdity to maintain the strings tension during the playing. meeting these requirements is an ongoing challenge for manufacturing because the wood used in the structure of the guitar neck is different as a speicies, as a structure, as physical-mechanical properties and rheological behavior. The paper containing mahogany-maple-mahogany and others containing masarnduba-maple-masaranduba. The samples were subjected to the three-point bending with different intensities of loads (400, 800, 1000, 1400 N), determining for each maximum deflection and the maximum stresses. It was found that the use of laminated wood increases the rigidity of the guitar neck and the bending resistance; the most advantageous combination is masaranduba-maple-masaranduba."

"Keywords: solid wood, glued laminated wood, guitar, three points bending, stifness, beam of constant strength"

RESULTS AND DISCUSSION

"Analyzing the values of maximum displacement in the force direction, it was found that samples from solid wood presents the greatest deflections, regardless of the applied load , which is about 120..250% higher than values obtained on laminated wood samples made from m asaranduba with maple (Fig. 4 a, b). This indicates that guitar neck stiffness can be increased by using a combination of least two wood species"

http://aspeckt.unitbv.ro/jspui/bitstream/123456789/2144/1/272-277%20Paper%20comat%202016%20Stanciu%20%28Engl%29. pdf

So what does that tell us? Does it tell us that a laminate neck is stronger than a solid neck? No. The proper way of doing this would be to use the same wood in the laminate as the solid piece. By adding different woods to the laminate sandwich it is no longer apples to apples comparison but rather apples to oranges. What if solid samples of the Mahogany and the Masaranduba were stronger than the solid Maple? Making a sandwich of them and the maple is naturally going to be stronger.

Sorry, I worked in a mechanical test lab and broke my share of samples. This paper is not worth a heck of a lot.

Diogenes Blue
05-09-2018, 05:49 PM
Most laminated necks include center strips of contrasting, quartersawn, woods that are often equally as strong or stronger than the main blank. Stronger more often than not. I think when builders talk about sandwiched necks, this is what we mean. Otherwise we'd be making bread sandwiches; small slices of bread between two pieces of bread, which doesn't seem very interesting or appetizing to me. Some, a few, are laminated from the same stock. I'd guess they'd be at least less susceptible to warping, possibly even stiffer, than a neck that hasn't been laminated, due to the opposing grain patterns. Wood goes where it wants to go, but it can be tamed, relaxed, stiffened, made stronger, by arranging it in various ways.

Here's an illustration.

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bsfloyd
05-10-2018, 03:11 AM
Another angle on this...just got on a LoPrinzi tenor, with a sandwiched (laminate) neck. The depth of the neck is thinner than most, so I assume the laminate neck provides additional strength, although I see some LoPrinzis without it.

This reminds me of the Ibanez Super Wizard electric guitar necks. They are about as thin (depth) as they come and they use a similar multi ply neck.

http://www.ibanez.com/products/u_eg_detail18.php?year=2018&cat_id=1&series_id=1&data_id=329&color=CL01

Diogenes Blue
05-10-2018, 06:59 AM
I'm a fan of the Super Wizard. That RG is one wicked nice guitar.