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In another thread there was reference to double laminated sides and even backs and even though there has probably been a thread re: same, I wondered if those who use this method could share their thoughts/experiences?

I use a solid lining and LOVE what it does for the stability of the box before top and back glue up, have no idea what it might do tonally, but the added stability is well worth the little extra effort.

If there were some empirical evidence that it effected tone in any sort of negative way I would re-think the proposition but the upside is large enough to continue - for now.

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Thank You and Best To All

There is one school of thought that stiff and heavy sides can improve the instrument. Laminated backs have not gained as wide of an acceptance. Greg Smallman is one of the better known builders to use laminated sides and pioneered lattice bracing.

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If you're looking for numbers you might want to read up on what Trevor Gore has to say about adding mass to sides and the effect that can have on tone. Trevor also writes about dead and live backs. Again, all backed up by numbers. Trevor writes about dead and live backs and that seems to be one of the things he writes about that gets taken the wrong way by a great many people.

As for laminating backs and sides...laminating gets a bad press. Mainly because of the association with cheap work. Here are a few guitars with laminated back and sides:

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nigel

http://www.theluthierblog.com

To reinforce Nigel's comments, I've been following Trevor Gore's direction and have traded several e-mails with him on weighting the sides of the guitar, laminated or not. In simple (simplistic?) terms, weighted sides give the top a better foundation in order to flex from the edge of the lower bout. Trevor notes that the node of the main top resonance, as indicated by Chladni patterns, moves out significantly if the sides are weighted. He advocates a solid (and heavy) lining for the same reason. I've followed his advice and find it effective. Additionally, there seems to be good evidence that whether a back is live or not, energy is transmitted to it primarily though air in the box rather than along the sides. This suggests that any damping in the sides due to lamination may not be important, but I don't know of any studies of that.

I am a big fan of double sides especially Mahogany. Mass can be overdone. A few years ago I worked on a classical that had lead mesh laminated between two Rosewood sides.

It was LOUD but didn’t sound very good.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Yep, if you make the sides very heavy and the top very thin, it is easy to end up with a guitar shaped banjo.

Trevor adds blocks of metal to add mass to his guitar sides. They are bolted into place. He can accurately tune a specific mode by adding the correct amount of mass. Though he does say that in general, guitars are improved by adding side mass. This can be done as he does, with bolt in blocks of metal. A more marketing-friendly way of adding mass is to go for double sides. It's normally sold as "increasing stiffness." According to Trevor, increasing stiffness has a lot less obvious effect than doubling the side mass, which is what happens when you glue two sets of ribs together.

One benefit of laminating back and sides is you gain access to a whole world of fancy looking timbers that you might not otherwise consider. Or be able to afford. Also, stability becomes less of an issue. As does how long you might store the wood before using it.

One piece pomelle bubinga back anyone?

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nigel

http://www.theluthierblog.com

I have been building some of my instruments with laminated sides and backs before it was commonly accepted in a hand made instrument. Unlike some builders, rather than trying to make them heavier, I have made them as similar to solid wood as possible, with I feel, similar results. I won't claim any great superiority for laminates, nor will I admit to any great detriment.
Building with laminates adds work some places and eliminates it in others. With some species of wood it can be an economical proposition and for others is more costly.
There is a learning curve (not insurmountable) for working with laminates, so until someone has built a few instruments it is probably better to work with solid materials.

Or how about a one piece slab sawn arched wenge back?

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nigel

http://www.theluthierblog.com

I recall a few years ago a classical builder demonstrating making a composite with some kind of dense foam between the wood veneers. I can’t remember the luthiers name, but I remember it was a respected luthier with top end instruments. His sides were 3/16” thick and very stiff, but not necessarily heavy.

Next time I feel I have the time for a little experimenting I might give it a try. As it is I use laminated sides. More to allow easy bending of highly figured woods than any other reason, but I’ve been very pleased with the sound. That said, my backs are very resonant, so I’m definitely in the live back solid sides camp.


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Gorgeous backs guitars Nigel. Are they laminated which allows for the single piece Wenge, Bubinga?

Do you laminate sides as well?

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Thank You and Best To All

Yep, back and sides are laminated. All from the same flitch of veneer. You get a lot more choice when you work this way. And if you find a flitch you like, you can get enough material for a lot of instruments without breaking the bank or having to take up a lot of space for storage.

Inside you can put whatever you like. For the backs I've used more veneer, reject tops, you can use nomex, foam. It's worth cross graining inside for stability, but I've also used Japanese shoji paper to cross grain. I read of one feller who used silk!.

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nigel

http://www.theluthierblog.com

THANK YOU!!

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Thank You and Best To All

One piece sapele back anyone?

How you approach customers with lamination makes a big difference. Some will never be interested, and that's fine. For many though, the eyes come first. Then come the ears. If they like what they see and what they hear, are open-minded, and trust the maker, you can make them a fantastic instrument.

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nigel

http://www.theluthierblog.com

I like to get more volume from my ukes and will sometimes use laminated sides . There is an excellent method shown in john bogdanovichs book on classical guitar making or his dvd,

I have never had a problem with ribs being laminated, but I'm one of those that believes in integrity of the back and top. I never did get to laminated ribs, but my mandolins all had very thick ribs and I do believe they contributed to the tonal qualities I got. I believe the thickness of the ribs helped eliminate the "contribution" to the total sound and helped isolate the top and back to tonal production.

However, when it comes to backs, I'm afraid I'm one of those that would "never be interested". The back is a secondary tone producer and if you laminate it, you have just added the glue to the tone producing properties of the back. Tap a solid back and you will find a very different tone to a tapped, laminated back.

Same with the top. Sure, some are getting results with laminated tops, but what exactly does it sound like? Now we step into the world of plywood guitars or instruments. I have a plywood KayKraft mandolin over 70 years old and while it sounds very good, it won't hold a candle to one of my F5's.

I know that I am not going to convince a one of you with my statements, but thought I would throw them out as an opinion. After all, it mostly comes down to what NK said, "The eyes come first". To me and Stradivarius it's always been "What does that wood sound like".

"To me and Stradivarius it's always been "What does that wood sound like"."

Hi Haans,
I gave some thought to your above statement, and decided I would go tap some wood. I work with both solid and laminated stuff. When I tapped solid pieces of rosewood (cocobolo, EIR) and rosewoods laminated with west system epoxy ( BRW - of similar dimensions), they all "bonked" about the same. A rather unscientific test I admit.

OK, you've "bonked" some wood and some plywood.
Clay, you may do as you like...we are on a different level of understanding.

Two layer laminated sides can be stiffer than solid wood and yet can be lighter in weight. Also less likely to crack.
Michael Greenfield does sides like this and his guitars go for +$20,000.
You can also check Tim McKnight's build over on AGF, he does great guitars.

Brent